Java 11 migrate remaining q-r (#1121)

* Moves queue-load-leveling to Java 11

* Moves reactor to Java 11

* Moves reader-writer-lock to Java 11

* Moves repository to Java 11

* Moves resource-acquisition-is-initialization to Java 11

* Moves retry to Java 11

* Moves role-object to Java 11

reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/App.java

@@ -23,11 +23,9 @@
 
 package com.iluwatar.reader.writer.lock;
 
-import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ThreadLocalRandom;
 import java.util.concurrent.TimeUnit;
-import java.util.stream.IntStream;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -58,19 +56,21 @@ public class App {
    */
   public static void main(String[] args) {
 
-    ExecutorService executeService = Executors.newFixedThreadPool(10);
-    ReaderWriterLock lock = new ReaderWriterLock();
+    var executeService = Executors.newFixedThreadPool(10);
+    var lock = new ReaderWriterLock();
 
     // Start writers
-    IntStream.range(0, 5)
-        .forEach(i -> executeService.submit(new Writer("Writer " + i, lock.writeLock(),
-            ThreadLocalRandom.current().nextLong(5000))));
+    for (var i = 0; i < 5; i++) {
+      var writingTime = ThreadLocalRandom.current().nextLong(5000);
+      executeService.submit(new Writer("Writer " + i, lock.writeLock(), writingTime));
+    }
     LOGGER.info("Writers added...");
 
     // Start readers
-    IntStream.range(0, 5)
-        .forEach(i -> executeService.submit(new Reader("Reader " + i, lock.readLock(),
-            ThreadLocalRandom.current().nextLong(10))));
+    for (var i = 0; i < 5; i++) {
+      var readingTime = ThreadLocalRandom.current().nextLong(10);
+      executeService.submit(new Reader("Reader " + i, lock.readLock(), readingTime));
+    }
     LOGGER.info("Readers added...");
 
     try {
@@ -81,9 +81,10 @@ public class App {
     }
 
     // Start readers
-    IntStream.range(6, 10)
-        .forEach(i -> executeService.submit(new Reader("Reader " + i, lock.readLock(),
-            ThreadLocalRandom.current().nextLong(10))));
+    for (var i = 6; i < 10; i++) {
+      var readingTime = ThreadLocalRandom.current().nextLong(10);
+      executeService.submit(new Reader("Reader " + i, lock.readLock(), readingTime));
+    }
     LOGGER.info("More readers added...");
 
 

reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/ReaderWriterLock.java

@@ -43,7 +43,7 @@ public class ReaderWriterLock implements ReadWriteLock {
   private static final Logger LOGGER = LoggerFactory.getLogger(ReaderWriterLock.class);
 
 
-  private Object readerMutex = new Object();
+  private final Object readerMutex = new Object();
 
   private int currentReaderCount;
 
@@ -57,7 +57,7 @@ public class ReaderWriterLock implements ReadWriteLock {
    *
    * <p>This is the most important field in this class to control the access for reader/writer.
    */
-  private Set<Object> globalMutex = new HashSet<>();
+  private final Set<Object> globalMutex = new HashSet<>();
 
   private ReadLock readerLock = new ReadLock();
   private WriteLock writerLock = new WriteLock();
@@ -114,8 +114,8 @@ public class ReaderWriterLock implements ReadWriteLock {
           try {
             globalMutex.wait();
           } catch (InterruptedException e) {
-            LOGGER
-                .info("InterruptedException while waiting for globalMutex in acquireForReaders", e);
+            var message = "InterruptedException while waiting for globalMutex in acquireForReaders";
+            LOGGER.info(message, e);
             Thread.currentThread().interrupt();
           }
         }
@@ -125,7 +125,6 @@ public class ReaderWriterLock implements ReadWriteLock {
 
     @Override
     public void unlock() {
-
       synchronized (readerMutex) {
         currentReaderCount--;
         // Release the lock only when it is the last reader, it is ensure that the lock is released
@@ -142,7 +141,7 @@ public class ReaderWriterLock implements ReadWriteLock {
     }
 
     @Override
-    public void lockInterruptibly() throws InterruptedException {
+    public void lockInterruptibly() {
       throw new UnsupportedOperationException();
     }
 
@@ -152,7 +151,7 @@ public class ReaderWriterLock implements ReadWriteLock {
     }
 
     @Override
-    public boolean tryLock(long time, TimeUnit unit) throws InterruptedException {
+    public boolean tryLock(long time, TimeUnit unit) {
       throw new UnsupportedOperationException();
     }
 
@@ -170,7 +169,6 @@ public class ReaderWriterLock implements ReadWriteLock {
 
     @Override
     public void lock() {
-
       synchronized (globalMutex) {
 
         // Wait until the lock is free.
@@ -189,7 +187,6 @@ public class ReaderWriterLock implements ReadWriteLock {
 
     @Override
     public void unlock() {
-
       synchronized (globalMutex) {
         globalMutex.remove(this);
         // Notify the waiter, other writer or reader
@@ -198,7 +195,7 @@ public class ReaderWriterLock implements ReadWriteLock {
     }
 
     @Override
-    public void lockInterruptibly() throws InterruptedException {
+    public void lockInterruptibly() {
       throw new UnsupportedOperationException();
     }
 
@@ -208,7 +205,7 @@ public class ReaderWriterLock implements ReadWriteLock {
     }
 
     @Override
-    public boolean tryLock(long time, TimeUnit unit) throws InterruptedException {
+    public boolean tryLock(long time, TimeUnit unit) {
       throw new UnsupportedOperationException();
     }