mirror of
https://github.com/tiennm99/java-design-patterns.git
synced 2026-05-14 10:58:42 +00:00
feature: Rewrite thread-local storage pattern (#2452)
This commit is contained in:
Eugene
@@ -59,7 +59,6 @@
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<module>abstract-factory</module>
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<module>collecting-parameter</module>
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<module>monitor</module>
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<module>tls</module>
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<module>builder</module>
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<module>factory-method</module>
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<module>prototype</module>
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@@ -205,6 +204,7 @@
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<module>identity-map</module>
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<module>component</module>
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<module>context-object</module>
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<module>thread-local-storage</module>
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</modules>
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<repositories>
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<repository>
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@@ -0,0 +1,247 @@
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---
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title: Thread-local storage
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category: Concurrency
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language: en
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tag:
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- Data access
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---
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## Intent
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Provide an ability to have a copy of a variable for each thread, making it thread-safe.
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## Explanation
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During code assembling compiler add _.tdata_ directive,
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which means that variables below will store in different places from thread to thread.
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This means changing variable in one thread won't affect the same variable in other thread.
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**Real world example**
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> On constructions each worker has its own shovel. When one of them broke his shovel,
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> other still can continue work due to they have own instrument.
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**In plain words**
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>Each thread will have its own copy of variable.
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**Wikipedia says**
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>Thread-local storage (TLS) is a computer programming method that uses static or global memory local to a thread.
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**Programmatic Example**
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To define variable in thread-local storage you just need to put it into Java's ThreadLocal, e.g:
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```java
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public class Main {
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private ThreadLocal<String> stringThreadLocal = new ThreadLocal<>();
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public void initialize(String value) {
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this.stringThreadLocal.set(value);
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}
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}
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```
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Below we will contact a variable from two threads at a time to see, why we need it.
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Main logic that show's current variable value is imposed in class AbstractThreadLocalExample, two implementations
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differs only in the **value store approach**.
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Main class:
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```java
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/**
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* Class with main per-thread logic.
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*/
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public abstract class AbstractThreadLocalExample implements Runnable {
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private static final Random RND = new Random();
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@Override
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public void run() {
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//Here we stop thread randomly
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LockSupport.parkNanos(RND.nextInt(1_000_000_000, 2_000_000_000));
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System.out.println(getCurrentThreadName() + ", before value changing: " + getter().get());
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setter().accept(RND.nextInt());
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}
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/**
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* Setter for our value.
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*
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* @return consumer
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*/
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protected abstract Consumer<Integer> setter();
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/**
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* Getter for our value.
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*
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* @return supplier
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*/
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protected abstract Supplier<Integer> getter();
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private String getCurrentThreadName() {
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return Thread.currentThread().getName();
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}
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}
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```
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And two implementations. With ThreadLocal:
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```java
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/**
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* Example of runnable with use of {@link ThreadLocal}.
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*/
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public class WithThreadLocal extends AbstractThreadLocalExample {
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private ThreadLocal<Integer> value;
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public WithThreadLocal(ThreadLocal<Integer> value) {
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this.value = value;
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}
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@Override
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protected Consumer<Integer> setter() {
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return value::set;
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}
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@Override
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protected Supplier<Integer> getter() {
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return value::get;
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}
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}
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```
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And the class that stores value in one shared for all threads place:
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```java
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/**
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* Example of runnable without usage of {@link ThreadLocal}.
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*/
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public class WithoutThreadLocal extends AbstractThreadLocalExample {
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private Integer value;
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public WithoutThreadLocal(Integer value) {
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this.value = value;
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}
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@Override
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protected Consumer<Integer> setter() {
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return integer -> value = integer;
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}
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@Override
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protected Supplier<Integer> getter() {
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return () -> value;
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}
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}
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```
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Guess we want to run these classes. We will construct both implementations and invoke _run_ method.
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So, we want to see initial value in console (thanks to System.out.println()). Let's take a look at tests.
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```java
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public class ThreadLocalTest {
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private final ByteArrayOutputStream outContent = new ByteArrayOutputStream();
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private final PrintStream originalOut = System.out;
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@BeforeEach
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public void setUpStreams() {
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System.setOut(new PrintStream(outContent));
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}
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@AfterEach
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public void restoreStreams() {
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System.setOut(originalOut);
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}
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@Test
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public void withoutThreadLocal() throws InterruptedException {
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int initialValue = 1234567890;
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int threadSize = 2;
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ExecutorService executor = Executors.newFixedThreadPool(threadSize);
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WithoutThreadLocal threadLocal = new WithoutThreadLocal(initialValue);
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for (int i = 0; i < threadSize; i++) {
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executor.submit(threadLocal);
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}
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executor.awaitTermination(3, TimeUnit.SECONDS);
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List<String> lines = outContent.toString().lines().toList();
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//Matches only first finished thread output, the second has changed by first thread value
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Assertions.assertFalse(lines.stream()
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.allMatch(line -> line.endsWith(String.valueOf(initialValue))));
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}
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@Test
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public void withThreadLocal() throws InterruptedException {
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int initialValue = 1234567890;
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int threadSize = 2;
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ExecutorService executor = Executors.newFixedThreadPool(threadSize);
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WithThreadLocal threadLocal = new WithThreadLocal(ThreadLocal.withInitial(() -> initialValue));
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for (int i = 0; i < threadSize; i++) {
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executor.submit(threadLocal);
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}
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executor.awaitTermination(3, TimeUnit.SECONDS);
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List<String> lines = outContent.toString().lines().toList();
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Assertions.assertTrue(lines.stream()
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.allMatch(line -> line.endsWith(String.valueOf(initialValue))));
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}
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}
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```
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The output of test named withThreadLocal:
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```
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pool-2-thread-2, before value changing: 1234567890
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pool-2-thread-1, before value changing: 1234567890
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```
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And the output of withoutThreadLocal:
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```
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pool-1-thread-2, before value changing: 1234567890
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pool-1-thread-1, before value changing: 848843054
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```
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Where 1234567890 - is our initial value. We see, that in test _withoutThreadLocal_
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thread 2 got out from LockSupport#parkNanos earlier than the first and
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change value in shared variable.
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## Class diagram
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```mermaid
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classDiagram
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class ThreadLocal
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ThreadLocal : get()
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ThreadLocal : initialValue()
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ThreadLocal : remove()
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ThreadLocal : set(T value)
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```
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## Applicability
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Use ThreadLocal when:
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- You need to run singleton with state in multiple threads
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- You need to use not thread-safe classes in concurrency program
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## Tutorials
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- [Baeldung](https://www.baeldung.com/java-threadlocal)
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## Known uses
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- In java.lang.Thread during thread initialization
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- In java.net.URL to prevent recursive provider lookups
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- In org.junit.runners.BlockJUnit4ClassRunner to contain current rule
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- In org.springframework:spring-web to store request context
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- In org.apache.util.net.Nio2Endpoint to allow detecting if a completion handler completes inline
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- In io.micrometer to avoid problems with not thread-safe NumberFormat
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## Credits
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- [Usage cases](https://chao-tic.github.io/blog/2018/12/25/tls)
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- [Implementation in Linux](https://uclibc.org/docs/tls.pdf)
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@@ -26,37 +26,21 @@
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-->
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<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
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<modelVersion>4.0.0</modelVersion>
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<parent>
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<groupId>com.iluwatar</groupId>
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<artifactId>java-design-patterns</artifactId>
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<version>1.26.0-SNAPSHOT</version>
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</parent>
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<artifactId>tls</artifactId>
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<dependencies>
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<dependency>
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<groupId>org.junit.jupiter</groupId>
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<artifactId>junit-jupiter-engine</artifactId>
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<scope>test</scope>
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</dependency>
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</dependencies>
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<build>
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<plugins>
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<plugin>
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<groupId>org.apache.maven.plugins</groupId>
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<artifactId>maven-assembly-plugin</artifactId>
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<executions>
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<execution>
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<configuration>
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<archive>
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<manifest>
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<mainClass>com.iluwatar.tls.App</mainClass>
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</manifest>
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</archive>
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</configuration>
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</execution>
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</executions>
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</plugin>
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</plugins>
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</build>
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<modelVersion>4.0.0</modelVersion>
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<parent>
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<groupId>com.iluwatar</groupId>
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<artifactId>java-design-patterns</artifactId>
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<version>1.26.0-SNAPSHOT</version>
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</parent>
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<artifactId>thread-local-storage</artifactId>
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<dependencies>
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<dependency>
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<groupId>org.junit.jupiter</groupId>
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<artifactId>junit-jupiter-engine</artifactId>
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<scope>test</scope>
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</dependency>
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</dependencies>
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</project>
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@@ -0,0 +1,44 @@
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package com.iluwatar;
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import java.security.SecureRandom;
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import java.util.concurrent.locks.LockSupport;
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import java.util.function.Consumer;
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import java.util.function.Supplier;
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/**
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* Class with main logic.
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*/
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public abstract class AbstractThreadLocalExample implements Runnable {
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private static final SecureRandom RND = new SecureRandom();
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private static final Integer RANDOM_THREAD_PARK_START = 1_000_000_000;
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private static final Integer RANDOM_THREAD_PARK_END = 2_000_000_000;
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@Override
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public void run() {
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long nanosToPark = RND.nextInt(RANDOM_THREAD_PARK_START, RANDOM_THREAD_PARK_END);
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LockSupport.parkNanos(nanosToPark);
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System.out.println(getThreadName() + ", before value changing: " + getter().get());
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setter().accept(RND.nextInt());
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}
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/**
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* Setter for our value.
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*
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* @return consumer
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*/
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protected abstract Consumer<Integer> setter();
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/**
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* Getter for our value.
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*
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* @return supplier
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*/
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protected abstract Supplier<Integer> getter();
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private String getThreadName() {
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return Thread.currentThread().getName();
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}
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}
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@@ -0,0 +1,31 @@
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package com.iluwatar;
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import java.util.function.Consumer;
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import java.util.function.Supplier;
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import lombok.AllArgsConstructor;
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/**
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* Example of runnable with use of {@link ThreadLocal}.
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*/
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@AllArgsConstructor
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public class WithThreadLocal extends AbstractThreadLocalExample {
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private final ThreadLocal<Integer> value;
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/**
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* Removes the current thread's value for this thread-local variable.
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*/
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public void remove() {
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this.value.remove();
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}
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@Override
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protected Consumer<Integer> setter() {
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return value::set;
|
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}
|
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@Override
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protected Supplier<Integer> getter() {
|
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return value::get;
|
||||
}
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}
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@@ -0,0 +1,24 @@
|
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package com.iluwatar;
|
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import java.util.function.Consumer;
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import java.util.function.Supplier;
|
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import lombok.AllArgsConstructor;
|
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|
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/**
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* Example of runnable without usage of {@link ThreadLocal}.
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*/
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@AllArgsConstructor
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public class WithoutThreadLocal extends AbstractThreadLocalExample {
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private Integer value;
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@Override
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protected Consumer<Integer> setter() {
|
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return integer -> value = integer;
|
||||
}
|
||||
|
||||
@Override
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protected Supplier<Integer> getter() {
|
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return () -> value;
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,68 @@
|
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import com.iluwatar.WithThreadLocal;
|
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import com.iluwatar.WithoutThreadLocal;
|
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import org.junit.jupiter.api.AfterEach;
|
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import org.junit.jupiter.api.Assertions;
|
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import org.junit.jupiter.api.BeforeEach;
|
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import org.junit.jupiter.api.Test;
|
||||
|
||||
import java.io.ByteArrayOutputStream;
|
||||
import java.io.PrintStream;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.ExecutorService;
|
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import java.util.concurrent.Executors;
|
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import java.util.concurrent.TimeUnit;
|
||||
|
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public class ThreadLocalTest {
|
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|
||||
private final ByteArrayOutputStream outContent = new ByteArrayOutputStream();
|
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private final PrintStream originalOut = System.out;
|
||||
|
||||
@BeforeEach
|
||||
public void setUpStreams() {
|
||||
System.setOut(new PrintStream(outContent));
|
||||
}
|
||||
|
||||
@AfterEach
|
||||
public void restoreStreams() {
|
||||
System.setOut(originalOut);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void withoutThreadLocal() throws InterruptedException {
|
||||
int initialValue = 1234567890;
|
||||
|
||||
int threadSize = 2;
|
||||
ExecutorService executor = Executors.newFixedThreadPool(threadSize);
|
||||
|
||||
WithoutThreadLocal threadLocal = new WithoutThreadLocal(initialValue);
|
||||
for (int i = 0; i < threadSize; i++) {
|
||||
executor.submit(threadLocal);
|
||||
}
|
||||
executor.awaitTermination(3, TimeUnit.SECONDS);
|
||||
|
||||
List<String> lines = outContent.toString().lines().toList();
|
||||
//Matches only first thread, the second has changed by first thread value
|
||||
Assertions.assertFalse(lines.stream()
|
||||
.allMatch(line -> line.endsWith(String.valueOf(initialValue))));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void withThreadLocal() throws InterruptedException {
|
||||
int initialValue = 1234567890;
|
||||
|
||||
int threadSize = 2;
|
||||
ExecutorService executor = Executors.newFixedThreadPool(threadSize);
|
||||
|
||||
WithThreadLocal threadLocal = new WithThreadLocal(ThreadLocal.withInitial(() -> initialValue));
|
||||
for (int i = 0; i < threadSize; i++) {
|
||||
executor.submit(threadLocal);
|
||||
}
|
||||
|
||||
executor.awaitTermination(3, TimeUnit.SECONDS);
|
||||
threadLocal.remove();
|
||||
|
||||
List<String> lines = outContent.toString().lines().toList();
|
||||
Assertions.assertTrue(lines.stream()
|
||||
.allMatch(line -> line.endsWith(String.valueOf(initialValue))));
|
||||
}
|
||||
}
|
||||
@@ -1,19 +0,0 @@
|
||||
---
|
||||
title: Thread Local Storage
|
||||
category: Idiom
|
||||
language: en
|
||||
tag:
|
||||
- Performance
|
||||
---
|
||||
|
||||
## Intent
|
||||
Securing variables global to a thread against being spoiled by other threads. That is needed if you use class variables or static variables in your Callable object or Runnable object that are not read-only.
|
||||
|
||||
## Class diagram
|
||||
|
||||
|
||||
## Applicability
|
||||
Use the Thread Local Storage in any of the following situations
|
||||
|
||||
* When you use class variables in your Callable / Runnable object that are not read-only and you use the same Callable instance in more than one thread running in parallel.
|
||||
* When you use static variables in your Callable / Runnable object that are not read-only and more than one instances of the Callable / Runnable may run in parallel threads.
|
||||
Binary file not shown.
|
Before Width: | Height: | Size: 34 KiB |
@@ -1,79 +0,0 @@
|
||||
<?xml version="1.0" encoding="UTF-8"?>
|
||||
<class-diagram version="1.1.13" icons="true" always-add-relationships="false" generalizations="true" realizations="true"
|
||||
associations="true" dependencies="false" nesting-relationships="true" router="FAN">
|
||||
<class id="1" language="java" name="com.iluwatar.tls.DateFormatCallable" project="PatternIluwatar"
|
||||
file="/PatternIluwatar/src/main/java/com/iluwatar/tls/DateFormatCallable.java" binary="false" corner="BOTTOM_RIGHT">
|
||||
<position height="-1" width="-1" x="503" y="227"/>
|
||||
<display autosize="true" stereotype="true" package="true" initial-value="false" signature="true"
|
||||
sort-features="false" accessors="true" visibility="true">
|
||||
<attributes public="true" package="true" protected="true" private="true" static="true"/>
|
||||
<operations public="true" package="true" protected="true" private="true" static="true"/>
|
||||
</display>
|
||||
</class>
|
||||
<interface id="2" language="java" name="java.util.concurrent.Callable" project="Intros"
|
||||
file="C:/interne/Programme/jdk8u60x64/jre/lib/rt.jar" binary="true" corner="BOTTOM_RIGHT">
|
||||
<position height="-1" width="-1" x="501" y="52"/>
|
||||
<display autosize="true" stereotype="true" package="true" initial-value="false" signature="true"
|
||||
sort-features="false" accessors="true" visibility="true">
|
||||
<attributes public="true" package="true" protected="true" private="true" static="true"/>
|
||||
<operations public="true" package="true" protected="true" private="true" static="true"/>
|
||||
</display>
|
||||
</interface>
|
||||
<class id="3" language="java" name="java.lang.ThreadLocal" project="Intros"
|
||||
file="C:/interne/Programme/jdk8u60x64/jre/lib/rt.jar" binary="true" corner="BOTTOM_RIGHT">
|
||||
<position height="-1" width="-1" x="111" y="284"/>
|
||||
<display autosize="true" stereotype="true" package="true" initial-value="false" signature="true"
|
||||
sort-features="false" accessors="true" visibility="true">
|
||||
<attributes public="true" package="true" protected="true" private="true" static="true"/>
|
||||
<operations public="true" package="true" protected="true" private="true" static="true"/>
|
||||
</display>
|
||||
</class>
|
||||
<class id="4" language="java" name="com.iluwatar.tls.App" project="PatternIluwatar"
|
||||
file="/PatternIluwatar/src/main/java/com/iluwatar/tls/App.java" binary="false" corner="BOTTOM_RIGHT">
|
||||
<position height="-1" width="-1" x="845" y="228"/>
|
||||
<display autosize="true" stereotype="true" package="true" initial-value="false" signature="true"
|
||||
sort-features="false" accessors="true" visibility="true">
|
||||
<attributes public="true" package="true" protected="true" private="true" static="true"/>
|
||||
<operations public="true" package="true" protected="true" private="true" static="true"/>
|
||||
</display>
|
||||
</class>
|
||||
<class id="5" language="java" name="com.iluwatar.tls.Result" project="PatternIluwatar"
|
||||
file="/PatternIluwatar/src/main/java/com/iluwatar/tls/Result.java" binary="false" corner="BOTTOM_RIGHT">
|
||||
<position height="-1" width="-1" x="673" y="459"/>
|
||||
<display autosize="true" stereotype="true" package="true" initial-value="false" signature="true"
|
||||
sort-features="false" accessors="true" visibility="true">
|
||||
<attributes public="true" package="true" protected="true" private="true" static="true"/>
|
||||
<operations public="true" package="true" protected="true" private="true" static="true"/>
|
||||
</display>
|
||||
</class>
|
||||
<dependency id="6">
|
||||
<end type="SOURCE" refId="1"/>
|
||||
<end type="TARGET" refId="5"/>
|
||||
</dependency>
|
||||
<association id="7">
|
||||
<end type="SOURCE" refId="1" navigable="false">
|
||||
<attribute id="8" name="df"/>
|
||||
<multiplicity id="9" minimum="0" maximum="1"/>
|
||||
</end>
|
||||
<end type="TARGET" refId="3" navigable="true"/>
|
||||
<display labels="true" multiplicity="true"/>
|
||||
</association>
|
||||
<realization id="10">
|
||||
<end type="SOURCE" refId="1"/>
|
||||
<end type="TARGET" refId="2"/>
|
||||
</realization>
|
||||
<dependency id="11">
|
||||
<end type="SOURCE" refId="4"/>
|
||||
<end type="TARGET" refId="5"/>
|
||||
</dependency>
|
||||
<dependency id="12">
|
||||
<end type="SOURCE" refId="4"/>
|
||||
<end type="TARGET" refId="1"/>
|
||||
</dependency>
|
||||
<classifier-display autosize="true" stereotype="true" package="true" initial-value="false" signature="true"
|
||||
sort-features="false" accessors="true" visibility="true">
|
||||
<attributes public="true" package="true" protected="true" private="true" static="true"/>
|
||||
<operations public="true" package="true" protected="true" private="true" static="true"/>
|
||||
</classifier-display>
|
||||
<association-display labels="true" multiplicity="true"/>
|
||||
</class-diagram>
|
||||
@@ -1,25 +0,0 @@
|
||||
@startuml
|
||||
package com.iluwatar.tls {
|
||||
class App {
|
||||
- LOGGER : Logger {static}
|
||||
+ App()
|
||||
+ main(args : String[]) {static}
|
||||
- printAndCountDates(res : Result) : int {static}
|
||||
- printAndCountExceptions(res : Result) : int {static}
|
||||
}
|
||||
class DateFormatCallable {
|
||||
- LOGGER : Logger {static}
|
||||
- dateValue : String
|
||||
- df : ThreadLocal<DateFormat>
|
||||
+ DateFormatCallable(inDateFormat : String, inDateValue : String)
|
||||
+ call() : Result
|
||||
}
|
||||
class Result {
|
||||
- dateList : List<Date>
|
||||
- exceptionList : List<String>
|
||||
+ Result()
|
||||
+ getDateList() : List<Date>
|
||||
+ getExceptionList() : List<String>
|
||||
}
|
||||
}
|
||||
@enduml
|
||||
@@ -1,143 +0,0 @@
|
||||
/*
|
||||
* This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
|
||||
*
|
||||
* The MIT License
|
||||
* Copyright © 2014-2022 Ilkka Seppälä
|
||||
*
|
||||
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
||||
* of this software and associated documentation files (the "Software"), to deal
|
||||
* in the Software without restriction, including without limitation the rights
|
||||
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||||
* copies of the Software, and to permit persons to whom the Software is
|
||||
* furnished to do so, subject to the following conditions:
|
||||
*
|
||||
* The above copyright notice and this permission notice shall be included in
|
||||
* all copies or substantial portions of the Software.
|
||||
*
|
||||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||||
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||||
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||||
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||||
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||||
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||||
* THE SOFTWARE.
|
||||
*/
|
||||
package com.iluwatar.tls;
|
||||
|
||||
import java.util.Calendar;
|
||||
import java.util.concurrent.Executors;
|
||||
import lombok.extern.slf4j.Slf4j;
|
||||
|
||||
/**
|
||||
* ThreadLocal pattern
|
||||
*
|
||||
* <p>This App shows how to create an isolated space per each thread. In this example the usage of
|
||||
* SimpleDateFormat is made to be thread-safe. This is an example of the ThreadLocal pattern.
|
||||
*
|
||||
* <p>By applying the ThreadLocal pattern you can keep track of application instances or locale
|
||||
* settings throughout the handling of a request. The ThreadLocal class works like a static
|
||||
* variable, with the exception that it is only bound to the current thread! This allows us to use
|
||||
* static variables in a thread-safe way.
|
||||
*
|
||||
* <p>In Java, thread-local variables are implemented by the ThreadLocal class object. ThreadLocal
|
||||
* holds a variable of type T, which is accessible via get/set methods.
|
||||
*
|
||||
* <p>SimpleDateFormat is one of the basic Java classes and is not thread-safe. If you do not
|
||||
* isolate the instance of SimpleDateFormat per each thread then problems arise.
|
||||
*
|
||||
* <p>App converts the String date value 15/12/2015 to the Date format using the Java class
|
||||
* SimpleDateFormat. It does this 20 times using 4 threads, each doing it 5 times. With the usage of
|
||||
* as ThreadLocal in DateFormatCallable everything runs well. But if you comment out the ThreadLocal
|
||||
* variant (marked with "//TLTL") and comment in the non ThreadLocal variant (marked with
|
||||
* "//NTLNTL") you can see what will happen without the ThreadLocal. Most likely you will get
|
||||
* incorrect date values and / or exceptions.
|
||||
*
|
||||
* <p>This example clearly show what will happen when using non thread-safe classes in a thread. In
|
||||
* real life this may happen one in of 1.000 or 10.000 conversions and those are really hard to find
|
||||
* errors.
|
||||
*
|
||||
* @author Thomas Bauer, 2017
|
||||
*/
|
||||
@Slf4j
|
||||
public class App {
|
||||
|
||||
/**
|
||||
* Program entry point.
|
||||
*
|
||||
* @param args command line args
|
||||
*/
|
||||
public static void main(String[] args) {
|
||||
var counterDateValues = 0;
|
||||
var counterExceptions = 0;
|
||||
|
||||
// Create a callable
|
||||
var callableDf = new DateFormatCallable("dd/MM/yyyy", "15/12/2015");
|
||||
// start 4 threads, each using the same Callable instance
|
||||
var executor = Executors.newCachedThreadPool();
|
||||
|
||||
var futureResult1 = executor.submit(callableDf);
|
||||
var futureResult2 = executor.submit(callableDf);
|
||||
var futureResult3 = executor.submit(callableDf);
|
||||
var futureResult4 = executor.submit(callableDf);
|
||||
try {
|
||||
var result = new Result[4];
|
||||
result[0] = futureResult1.get();
|
||||
result[1] = futureResult2.get();
|
||||
result[2] = futureResult3.get();
|
||||
result[3] = futureResult4.get();
|
||||
|
||||
// Print results of thread executions (converted dates and raised exceptions)
|
||||
// and count them
|
||||
for (var value : result) {
|
||||
counterDateValues = counterDateValues + printAndCountDates(value);
|
||||
counterExceptions = counterExceptions + printAndCountExceptions(value);
|
||||
}
|
||||
|
||||
// a correct run should deliver 20 times 15.12.2015
|
||||
// and a correct run shouldn't deliver any exception
|
||||
LOGGER.info("The List dateList contains " + counterDateValues + " date values");
|
||||
LOGGER.info("The List exceptionList contains " + counterExceptions + " exceptions");
|
||||
|
||||
} catch (Exception e) {
|
||||
LOGGER.info("Abnormal end of program. Program throws exception: " + e);
|
||||
}
|
||||
executor.shutdown();
|
||||
}
|
||||
|
||||
/**
|
||||
* Print result (date values) of a thread execution and count dates.
|
||||
*
|
||||
* @param res contains results of a thread execution
|
||||
*/
|
||||
private static int printAndCountDates(Result res) {
|
||||
// a correct run should deliver 5 times 15.12.2015 per each thread
|
||||
var counter = 0;
|
||||
for (var dt : res.getDateList()) {
|
||||
counter++;
|
||||
var cal = Calendar.getInstance();
|
||||
cal.setTime(dt);
|
||||
// Formatted output of the date value: DD.MM.YYYY
|
||||
LOGGER.info(cal.get(Calendar.DAY_OF_MONTH) + "."
|
||||
+ cal.get(Calendar.MONTH) + "."
|
||||
+ cal.get(Calendar.YEAR)
|
||||
);
|
||||
}
|
||||
return counter;
|
||||
}
|
||||
|
||||
/**
|
||||
* Print result (exceptions) of a thread execution and count exceptions.
|
||||
*
|
||||
* @param res contains results of a thread execution
|
||||
* @return number of dates
|
||||
*/
|
||||
private static int printAndCountExceptions(Result res) {
|
||||
// a correct run shouldn't deliver any exception
|
||||
var counter = 0;
|
||||
for (var ex : res.getExceptionList()) {
|
||||
counter++;
|
||||
LOGGER.info(ex);
|
||||
}
|
||||
return counter;
|
||||
}
|
||||
}
|
||||
@@ -1,93 +0,0 @@
|
||||
/*
|
||||
* This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
|
||||
*
|
||||
* The MIT License
|
||||
* Copyright © 2014-2022 Ilkka Seppälä
|
||||
*
|
||||
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
||||
* of this software and associated documentation files (the "Software"), to deal
|
||||
* in the Software without restriction, including without limitation the rights
|
||||
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||||
* copies of the Software, and to permit persons to whom the Software is
|
||||
* furnished to do so, subject to the following conditions:
|
||||
*
|
||||
* The above copyright notice and this permission notice shall be included in
|
||||
* all copies or substantial portions of the Software.
|
||||
*
|
||||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||||
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||||
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||||
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||||
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||||
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||||
* THE SOFTWARE.
|
||||
*/
|
||||
package com.iluwatar.tls;
|
||||
|
||||
import java.text.DateFormat;
|
||||
import java.text.SimpleDateFormat;
|
||||
import java.util.concurrent.Callable;
|
||||
import java.util.stream.IntStream;
|
||||
import lombok.extern.slf4j.Slf4j;
|
||||
|
||||
/**
|
||||
* DateFormatCallable converts string dates to a date format using SimpleDateFormat. The date format
|
||||
* and the date value will be passed to the Callable by the constructor. The constructor creates a
|
||||
* instance of SimpleDateFormat and stores it in a ThreadLocal class variable. For the complete
|
||||
* description of the example see {@link App}.
|
||||
*
|
||||
* <p>You can comment out the code marked with //TLTL and comment in the code marked //NTLNTL. Then
|
||||
* you can see what will happen if you do not use the ThreadLocal. For details see the description
|
||||
* of {@link App}
|
||||
*
|
||||
* @author Thomas Bauer, 2017
|
||||
*/
|
||||
@Slf4j
|
||||
public class DateFormatCallable implements Callable<Result> {
|
||||
|
||||
// class variables (members)
|
||||
private final ThreadLocal<DateFormat> df; //TLTL
|
||||
// private DateFormat df; //NTLNTL
|
||||
|
||||
private final String dateValue; // for dateValue Thread Local not needed
|
||||
|
||||
|
||||
/**
|
||||
* The date format and the date value are passed to the constructor.
|
||||
*
|
||||
* @param inDateFormat string date format string, e.g. "dd/MM/yyyy"
|
||||
* @param inDateValue string date value, e.g. "21/06/2016"
|
||||
*/
|
||||
public DateFormatCallable(String inDateFormat, String inDateValue) {
|
||||
final var idf = inDateFormat; //TLTL
|
||||
this.df = ThreadLocal.withInitial(() -> { //TLTL
|
||||
return new SimpleDateFormat(idf); //TLTL
|
||||
}); //TLTL
|
||||
// this.df = new SimpleDateFormat(inDateFormat); //NTLNTL
|
||||
this.dateValue = inDateValue;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Result call() {
|
||||
LOGGER.info(Thread.currentThread() + " started executing...");
|
||||
var result = new Result();
|
||||
|
||||
// Convert date value to date 5 times
|
||||
IntStream.rangeClosed(1, 5).forEach(i -> {
|
||||
try {
|
||||
// this is the statement where it is important to have the
|
||||
// instance of SimpleDateFormat locally
|
||||
// Create the date value and store it in dateList
|
||||
result.getDateList().add(this.df.get().parse(this.dateValue)); //TLTL
|
||||
// result.getDateList().add(this.df.parse(this.dateValue)); //NTLNTL
|
||||
} catch (Exception e) {
|
||||
// write the Exception to a list and continue work
|
||||
result.getExceptionList().add(e.getClass() + ": " + e.getMessage());
|
||||
}
|
||||
});
|
||||
|
||||
LOGGER.info("{} finished processing part of the thread", Thread.currentThread());
|
||||
|
||||
return result;
|
||||
}
|
||||
}
|
||||
@@ -1,66 +0,0 @@
|
||||
/*
|
||||
* This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
|
||||
*
|
||||
* The MIT License
|
||||
* Copyright © 2014-2022 Ilkka Seppälä
|
||||
*
|
||||
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
||||
* of this software and associated documentation files (the "Software"), to deal
|
||||
* in the Software without restriction, including without limitation the rights
|
||||
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||||
* copies of the Software, and to permit persons to whom the Software is
|
||||
* furnished to do so, subject to the following conditions:
|
||||
*
|
||||
* The above copyright notice and this permission notice shall be included in
|
||||
* all copies or substantial portions of the Software.
|
||||
*
|
||||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||||
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||||
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||||
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||||
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||||
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||||
* THE SOFTWARE.
|
||||
*/
|
||||
/*
|
||||
* Fiducia IT AG, All rights reserved. Use is subject to license terms.
|
||||
*/
|
||||
|
||||
package com.iluwatar.tls;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.Date;
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* Result object that will be returned by the Callable {@link DateFormatCallable} used in {@link
|
||||
* App}.
|
||||
*
|
||||
* @author Thomas Bauer, 2017
|
||||
*/
|
||||
public class Result {
|
||||
// A list to collect the date values created in one thread
|
||||
private final List<Date> dateList = new ArrayList<>();
|
||||
|
||||
// A list to collect Exceptions thrown in one threads (should be none in
|
||||
// this example)
|
||||
private final List<String> exceptionList = new ArrayList<>();
|
||||
|
||||
/**
|
||||
* Get list of date values collected within a thread execution.
|
||||
*
|
||||
* @return List of date values collected within an thread execution
|
||||
*/
|
||||
public List<Date> getDateList() {
|
||||
return dateList;
|
||||
}
|
||||
|
||||
/**
|
||||
* Get list of exceptions thrown within a thread execution.
|
||||
*
|
||||
* @return List of exceptions thrown within an thread execution
|
||||
*/
|
||||
public List<String> getExceptionList() {
|
||||
return exceptionList;
|
||||
}
|
||||
}
|
||||
@@ -1,41 +0,0 @@
|
||||
/*
|
||||
* This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
|
||||
*
|
||||
* The MIT License
|
||||
* Copyright © 2014-2022 Ilkka Seppälä
|
||||
*
|
||||
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
||||
* of this software and associated documentation files (the "Software"), to deal
|
||||
* in the Software without restriction, including without limitation the rights
|
||||
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||||
* copies of the Software, and to permit persons to whom the Software is
|
||||
* furnished to do so, subject to the following conditions:
|
||||
*
|
||||
* The above copyright notice and this permission notice shall be included in
|
||||
* all copies or substantial portions of the Software.
|
||||
*
|
||||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||||
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||||
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||||
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||||
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||||
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||||
* THE SOFTWARE.
|
||||
*/
|
||||
package com.iluwatar.tls;
|
||||
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
|
||||
|
||||
/**
|
||||
* Tests that thread local storage example runs without errors.
|
||||
*
|
||||
* @author Thomas Bauer, January 2017
|
||||
*/
|
||||
class AppTest {
|
||||
@Test
|
||||
void shouldExecuteApplicationWithoutException() {
|
||||
assertDoesNotThrow(() -> App.main(new String[]{}));
|
||||
}
|
||||
}
|
||||
@@ -1,147 +0,0 @@
|
||||
/*
|
||||
* This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
|
||||
*
|
||||
* The MIT License
|
||||
* Copyright © 2014-2022 Ilkka Seppälä
|
||||
*
|
||||
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
||||
* of this software and associated documentation files (the "Software"), to deal
|
||||
* in the Software without restriction, including without limitation the rights
|
||||
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||||
* copies of the Software, and to permit persons to whom the Software is
|
||||
* furnished to do so, subject to the following conditions:
|
||||
*
|
||||
* The above copyright notice and this permission notice shall be included in
|
||||
* all copies or substantial portions of the Software.
|
||||
*
|
||||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||||
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||||
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||||
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||||
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||||
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||||
* THE SOFTWARE.
|
||||
*/
|
||||
package com.iluwatar.tls;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertEquals;
|
||||
import static org.junit.jupiter.api.Assertions.fail;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.Calendar;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.Executors;
|
||||
import org.junit.jupiter.api.BeforeAll;
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
/**
|
||||
* Test of the Callable
|
||||
* <p>
|
||||
* In this test {@link DateFormatCallable} is tested with only one thread (i.e. without concurrency
|
||||
* situation)
|
||||
* <p>
|
||||
* After a successful run 5 date values should be in the result object. All dates should have the
|
||||
* same value (15.11.2015). To avoid problems with time zone not the date instances themselves are
|
||||
* compared by the test. For the test the dates are converted into string format DD.MM.YYY
|
||||
* <p>
|
||||
* Additionally the number of list entries are tested for both the list with the date values and the
|
||||
* list with the exceptions
|
||||
*
|
||||
* @author Thomas Bauer, January 2017
|
||||
*/
|
||||
class DateFormatCallableTest {
|
||||
|
||||
// Class variables used in setup() have to be static because setup() has to be static
|
||||
/**
|
||||
* Result object given back by DateFormatCallable -- Array with converted date values -- Array
|
||||
* with thrown exceptions
|
||||
*/
|
||||
private static Result result;
|
||||
|
||||
/**
|
||||
* The date values created by the run of of DateFormatRunnalbe. List will be filled in the setup()
|
||||
* method
|
||||
*/
|
||||
private static List<String> createdDateValues = new ArrayList<>();
|
||||
|
||||
/**
|
||||
* Expected number of date values in the date value list created by the run of DateFormatRunnalbe
|
||||
*/
|
||||
private final int expectedCounterDateValues = 5;
|
||||
|
||||
/**
|
||||
* Expected number of exceptions in the exception list created by the run of DateFormatRunnalbe.
|
||||
*/
|
||||
private final int expectedCounterExceptions = 0;
|
||||
|
||||
/**
|
||||
* Expected content of the list containing the date values created by the run of
|
||||
* DateFormatRunnalbe
|
||||
*/
|
||||
private final List<String> expectedDateValues =
|
||||
List.of("15.11.2015", "15.11.2015", "15.11.2015", "15.11.2015", "15.11.2015");
|
||||
|
||||
/**
|
||||
* Run Callable and prepare results for usage in the test methods
|
||||
*/
|
||||
@BeforeAll
|
||||
public static void setup() {
|
||||
// Create a callable
|
||||
var callableDf = new DateFormatCallable("dd/MM/yyyy", "15/12/2015");
|
||||
// start thread using the Callable instance
|
||||
var executor = Executors.newCachedThreadPool();
|
||||
var futureResult = executor.submit(callableDf);
|
||||
try {
|
||||
result = futureResult.get();
|
||||
createdDateValues = convertDatesToString(result);
|
||||
} catch (Exception e) {
|
||||
fail("Setup failed: " + e);
|
||||
}
|
||||
executor.shutdown();
|
||||
}
|
||||
|
||||
private static List<String> convertDatesToString(Result res) {
|
||||
// Format date value as DD.MM.YYYY
|
||||
if (res == null || res.getDateList() == null || res.getDateList().size() == 0) {
|
||||
return null;
|
||||
}
|
||||
var returnList = new ArrayList<String>();
|
||||
|
||||
for (var dt : res.getDateList()) {
|
||||
var cal = Calendar.getInstance();
|
||||
cal.setTime(dt);
|
||||
returnList.add(cal.get(Calendar.DAY_OF_MONTH) + "."
|
||||
+ cal.get(Calendar.MONTH) + "."
|
||||
+ cal.get(Calendar.YEAR)
|
||||
);
|
||||
}
|
||||
return returnList;
|
||||
}
|
||||
|
||||
/**
|
||||
* Test date values after the run of DateFormatRunnalbe. A correct run should deliver 5 times
|
||||
* 15.12.2015
|
||||
*/
|
||||
@Test
|
||||
void testDateValues() {
|
||||
assertEquals(expectedDateValues, createdDateValues);
|
||||
}
|
||||
|
||||
/**
|
||||
* Test number of dates in the list after the run of DateFormatRunnalbe. A correct run should
|
||||
* deliver 5 date values
|
||||
*/
|
||||
@Test
|
||||
void testCounterDateValues() {
|
||||
assertEquals(expectedCounterDateValues, result.getDateList().size());
|
||||
}
|
||||
|
||||
/**
|
||||
* Test number of Exceptions in the list after the run of DateFormatRunnalbe. A correct run should
|
||||
* deliver no exceptions
|
||||
*/
|
||||
@Test
|
||||
void testCounterExceptions() {
|
||||
assertEquals(expectedCounterExceptions, result.getExceptionList().size());
|
||||
}
|
||||
}
|
||||
@@ -1,121 +0,0 @@
|
||||
/*
|
||||
* This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
|
||||
*
|
||||
* The MIT License
|
||||
* Copyright © 2014-2022 Ilkka Seppälä
|
||||
*
|
||||
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
||||
* of this software and associated documentation files (the "Software"), to deal
|
||||
* in the Software without restriction, including without limitation the rights
|
||||
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||||
* copies of the Software, and to permit persons to whom the Software is
|
||||
* furnished to do so, subject to the following conditions:
|
||||
*
|
||||
* The above copyright notice and this permission notice shall be included in
|
||||
* all copies or substantial portions of the Software.
|
||||
*
|
||||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||||
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||||
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||||
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||||
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||||
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||||
* THE SOFTWARE.
|
||||
*/
|
||||
package com.iluwatar.tls;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertEquals;
|
||||
import static org.junit.jupiter.api.Assertions.fail;
|
||||
|
||||
import java.util.List;
|
||||
import java.util.concurrent.Executors;
|
||||
import org.junit.jupiter.api.BeforeAll;
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
/**
|
||||
* Test of the Callable
|
||||
* <p>
|
||||
* In this test {@link DateFormatCallable} is tested with only one thread (i.e. without concurrency
|
||||
* situation)
|
||||
* <p>
|
||||
* An incorrect formatted date is passed to the Callable After a successful run 0 date values and 5
|
||||
* exceptions should be in the result object.
|
||||
*
|
||||
* @author Thomas Bauer, January 2017
|
||||
*/
|
||||
public class DateFormatCallableTestIncorrectDateFormat {
|
||||
|
||||
// Class variables used in setup() have to be static because setup() has to be static
|
||||
/**
|
||||
* Result object given back by DateFormatCallable -- Array with converted date values -- Array
|
||||
* with thrown exceptions
|
||||
*/
|
||||
private static Result result;
|
||||
|
||||
/**
|
||||
* Expected number of date values in the date value list created by the run of DateFormatRunnalbe
|
||||
*/
|
||||
private final int expectedCounterDateValues = 0;
|
||||
|
||||
/**
|
||||
* Expected number of exceptions in the exception list created by the run of DateFormatRunnalbe.
|
||||
*/
|
||||
private final int expectedCounterExceptions = 5;
|
||||
|
||||
/**
|
||||
* Expected content of the list containing the exceptions created by the run of
|
||||
* DateFormatRunnalbe
|
||||
*/
|
||||
private final List<String> expectedExceptions = List.of(
|
||||
"class java.text.ParseException: Unparseable date: \"15.12.2015\"",
|
||||
"class java.text.ParseException: Unparseable date: \"15.12.2015\"",
|
||||
"class java.text.ParseException: Unparseable date: \"15.12.2015\"",
|
||||
"class java.text.ParseException: Unparseable date: \"15.12.2015\"",
|
||||
"class java.text.ParseException: Unparseable date: \"15.12.2015\""
|
||||
);
|
||||
|
||||
/**
|
||||
* Run Callable and prepare results for usage in the test methods
|
||||
*/
|
||||
@BeforeAll
|
||||
public static void setup() {
|
||||
// Create a callable. Pass a string date value not matching the format string
|
||||
var callableDf = new DateFormatCallable("dd/MM/yyyy", "15.12.2015");
|
||||
// start thread using the Callable instance
|
||||
var executor = Executors.newCachedThreadPool();
|
||||
var futureResult = executor.submit(callableDf);
|
||||
try {
|
||||
result = futureResult.get();
|
||||
} catch (Exception e) {
|
||||
fail("Setup failed: " + e);
|
||||
}
|
||||
executor.shutdown();
|
||||
}
|
||||
|
||||
/**
|
||||
* Test Exceptions after the run of DateFormatRunnalbe. A correct run should deliver 5 times the
|
||||
* same exception
|
||||
*/
|
||||
@Test
|
||||
void testExceptions() {
|
||||
assertEquals(expectedExceptions, result.getExceptionList());
|
||||
}
|
||||
|
||||
/**
|
||||
* Test number of dates in the list after the run of DateFormatRunnalbe. A correct run should
|
||||
* deliver no date values
|
||||
*/
|
||||
@Test
|
||||
void testCounterDateValues() {
|
||||
assertEquals(expectedCounterDateValues, result.getDateList().size());
|
||||
}
|
||||
|
||||
/**
|
||||
* Test number of Exceptions in the list after the run of DateFormatRunnalbe. A correct run should
|
||||
* deliver 5 exceptions
|
||||
*/
|
||||
@Test
|
||||
void testCounterExceptions() {
|
||||
assertEquals(expectedCounterExceptions, result.getExceptionList().size());
|
||||
}
|
||||
}
|
||||
@@ -1,165 +0,0 @@
|
||||
/*
|
||||
* This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
|
||||
*
|
||||
* The MIT License
|
||||
* Copyright © 2014-2022 Ilkka Seppälä
|
||||
*
|
||||
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
||||
* of this software and associated documentation files (the "Software"), to deal
|
||||
* in the Software without restriction, including without limitation the rights
|
||||
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||||
* copies of the Software, and to permit persons to whom the Software is
|
||||
* furnished to do so, subject to the following conditions:
|
||||
*
|
||||
* The above copyright notice and this permission notice shall be included in
|
||||
* all copies or substantial portions of the Software.
|
||||
*
|
||||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||||
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||||
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||||
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||||
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||||
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||||
* THE SOFTWARE.
|
||||
*/
|
||||
package com.iluwatar.tls;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertEquals;
|
||||
import static org.junit.jupiter.api.Assertions.fail;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.Calendar;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.Executors;
|
||||
import org.junit.jupiter.api.BeforeAll;
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
/**
|
||||
* Test of the Callable
|
||||
* <p>
|
||||
* In this test {@link DateFormatCallable} is used by 4 threads in parallel
|
||||
* <p>
|
||||
* After a successful run 5 date values should be in the result object of each thread. All dates
|
||||
* should have the same value (15.11.2015). To avoid problems with time zone not the date instances
|
||||
* themselves are compared by the test. For the test the dates are converted into string format
|
||||
* DD.MM.YYY
|
||||
* <p>
|
||||
* Additionally the number of list entries are tested for both the list with the date values and the
|
||||
* list with the exceptions
|
||||
*
|
||||
* @author Thomas Bauer, January 2017
|
||||
*/
|
||||
public class DateFormatCallableTestMultiThread {
|
||||
|
||||
// Class variables used in setup() have to be static because setup() has to be static
|
||||
/**
|
||||
* Result object given back by DateFormatCallable, one for each thread -- Array with converted
|
||||
* date values -- Array with thrown exceptions
|
||||
*/
|
||||
private static final Result[] result = new Result[4];
|
||||
|
||||
/**
|
||||
* The date values created by the run of of DateFormatRunnalbe. List will be filled in the setup()
|
||||
* method
|
||||
*/
|
||||
@SuppressWarnings("serial")
|
||||
private static class StringArrayList extends ArrayList<String> {
|
||||
/* nothing needed here */
|
||||
}
|
||||
|
||||
private static final List<String>[] createdDateValues = new StringArrayList[4];
|
||||
|
||||
/**
|
||||
* Expected number of date values in the date value list created by each thread
|
||||
*/
|
||||
private final int expectedCounterDateValues = 5;
|
||||
|
||||
/**
|
||||
* Expected number of exceptions in the exception list created by each thread
|
||||
*/
|
||||
private final int expectedCounterExceptions = 0;
|
||||
|
||||
/**
|
||||
* Expected content of the list containing the date values created by each thread
|
||||
*/
|
||||
private final List<String> expectedDateValues =
|
||||
List.of("15.11.2015", "15.11.2015", "15.11.2015", "15.11.2015", "15.11.2015");
|
||||
|
||||
/**
|
||||
* Run Callable and prepare results for usage in the test methods
|
||||
*/
|
||||
@BeforeAll
|
||||
public static void setup() {
|
||||
// Create a callable
|
||||
var callableDf = new DateFormatCallable("dd/MM/yyyy", "15/12/2015");
|
||||
// start thread using the Callable instance
|
||||
var executor = Executors.newCachedThreadPool();
|
||||
var futureResult1 = executor.submit(callableDf);
|
||||
var futureResult2 = executor.submit(callableDf);
|
||||
var futureResult3 = executor.submit(callableDf);
|
||||
var futureResult4 = executor.submit(callableDf);
|
||||
try {
|
||||
result[0] = futureResult1.get();
|
||||
result[1] = futureResult2.get();
|
||||
result[2] = futureResult3.get();
|
||||
result[3] = futureResult4.get();
|
||||
for (var i = 0; i < result.length; i++) {
|
||||
createdDateValues[i] = convertDatesToString(result[i]);
|
||||
}
|
||||
} catch (Exception e) {
|
||||
fail("Setup failed: " + e);
|
||||
}
|
||||
executor.shutdown();
|
||||
}
|
||||
|
||||
private static List<String> convertDatesToString(Result res) {
|
||||
// Format date value as DD.MM.YYYY
|
||||
if (res == null || res.getDateList() == null || res.getDateList().size() == 0) {
|
||||
return null;
|
||||
}
|
||||
var returnList = new StringArrayList();
|
||||
|
||||
for (var dt : res.getDateList()) {
|
||||
var cal = Calendar.getInstance();
|
||||
cal.setTime(dt);
|
||||
returnList.add(cal.get(Calendar.DAY_OF_MONTH) + "."
|
||||
+ cal.get(Calendar.MONTH) + "."
|
||||
+ cal.get(Calendar.YEAR)
|
||||
);
|
||||
}
|
||||
return returnList;
|
||||
}
|
||||
|
||||
/**
|
||||
* Test date values after the run of DateFormatRunnalbe. A correct run should deliver 5 times
|
||||
* 15.12.2015 by each thread
|
||||
*/
|
||||
@Test
|
||||
void testDateValues() {
|
||||
for (var createdDateValue : createdDateValues) {
|
||||
assertEquals(expectedDateValues, createdDateValue);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Test number of dates in the list after the run of DateFormatRunnalbe. A correct run should
|
||||
* deliver 5 date values by each thread
|
||||
*/
|
||||
@Test
|
||||
void testCounterDateValues() {
|
||||
for (var value : result) {
|
||||
assertEquals(expectedCounterDateValues, value.getDateList().size());
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Test number of Exceptions in the list after the run of DateFormatRunnalbe. A correct run should
|
||||
* deliver no exceptions
|
||||
*/
|
||||
@Test
|
||||
void testCounterExceptions() {
|
||||
for (var value : result) {
|
||||
assertEquals(expectedCounterExceptions, value.getExceptionList().size());
|
||||
}
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user