mirror of
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* #1261 Added base directories, folders, and file for the collecting parameter design pattern. * #1261 Added initial comment * #1261 Added Maven Dependencies * #1261 Added Maven Dependencies * #1261 Finished README.md file * #1261 Added tests * #1261 Code adheres to the standard * #1261 Code adheres to the standard * #1261 Code adheres to the standard * #1261 - Added table to README.md - Explicitly state that result is the collecting parameter - Improved applicability - Separated PrinterItem.java from PrinterQueue.java - Tests work now - Giant comment split * #1261 fixed programmatic example in README.md. * #1261 updated class diagram * #1261 Fixed everything. * #1261 Minor edit to README.md. * #1261 Minor edit to README.md. * #1261 Minor updates. * #1261 Fixed code style. * #1261 Removed getPrinterQueue test * #1261 Removed code smells * #1261 Added UML plugin. * #1261 Dependencies resolved. * #1261 Specified the UML diagram paths. Perhaps this will work. * #1261 pom.xml updated with UML wrapper. Maybe this will create class diagram when built? * #1261 UML added. * #1261 - README.md obeys the YAML requirements - Typo in README.md fixed - UMLWrapper removed from module pom.xml - More comments added Should be able to merge now :)
This commit is contained in:
JoshuaSinglaANU
@@ -0,0 +1,197 @@
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---
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title: Collecting Parameter
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category: Idiom
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language: en
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tags:
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- Generic
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---
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## Name
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Collecting Parameter
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## Intent
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To store the collaborative result of numerous methods within a collection.
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## Explanation
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### Real-world example
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Within a large corporate building, there exists a global printer queue that is a collection of all the printing jobs
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that are currently pending. Various floors contain different models of printers, each having a different printing
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policy. We must construct a program that can continually add appropriate printing jobs to a collection, which is called the *collecting parameter*.
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### In plain words
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Instead of having one giant method that contains numerous policies for collecting information into a variable, we can
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create numerous smaller functions that each take parameter, and append new information. We can pass the parameter to
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all of these smaller functions and by the end, we will have what we wanted originally. This time, the code is cleaner
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and easier to understand. Because the larger function has been broken down, the code is also easier to modify as changes
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are localised to the smaller functions.
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### Wikipedia says
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In the Collecting Parameter idiom a collection (list, map, etc.) is passed repeatedly as a parameter to a method which adds items to the collection.
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### Programmatic example
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Coding our example from above, we may use the collection `result` as a collecting parameter. The following restrictions
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are implemented:
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- If an A4 paper is coloured, it must also be single-sided. All other non-coloured papers are accepted
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- A3 papers must be non-coloured and single-sided
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- A2 papers must be single-page, single-sided, and non-coloured
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```java
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package com.iluwatar.collectingparameter;
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import java.util.LinkedList;
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import java.util.Queue;
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public class App {
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static PrinterQueue printerQueue = PrinterQueue.getInstance();
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/**
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* Program entry point.
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*
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* @param args command line args
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*/
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public static void main(String[] args) {
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/*
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Initialising the printer queue with jobs
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*/
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printerQueue.addPrinterItem(new PrinterItem(PaperSizes.A4, 5, false, false));
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printerQueue.addPrinterItem(new PrinterItem(PaperSizes.A3, 2, false, false));
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printerQueue.addPrinterItem(new PrinterItem(PaperSizes.A2, 5, false, false));
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/*
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This variable is the collecting parameter.
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*/
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var result = new LinkedList<PrinterItem>();
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/*
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* Using numerous sub-methods to collaboratively add information to the result collecting parameter
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*/
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addA4Papers(result);
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addA3Papers(result);
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addA2Papers(result);
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}
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}
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```
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We use the `addA4Paper`, `addA3Paper`, and `addA2Paper` methods to populate the `result` collecting parameter with the
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appropriate print jobs as per the policy described previously. The three policies are encoded below,
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```java
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public class App {
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static PrinterQueue printerQueue = PrinterQueue.getInstance();
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/**
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* Adds A4 document jobs to the collecting parameter according to some policy that can be whatever the client
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* (the print center) wants.
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*
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* @param printerItemsCollection the collecting parameter
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*/
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public static void addA4Papers(Queue<PrinterItem> printerItemsCollection) {
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/*
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Iterate through the printer queue, and add A4 papers according to the correct policy to the collecting parameter,
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which is 'printerItemsCollection' in this case.
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*/
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for (PrinterItem nextItem : printerQueue.getPrinterQueue()) {
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if (nextItem.paperSize.equals(PaperSizes.A4)) {
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var isColouredAndSingleSided = nextItem.isColour && !nextItem.isDoubleSided;
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if (isColouredAndSingleSided) {
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printerItemsCollection.add(nextItem);
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} else if (!nextItem.isColour) {
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printerItemsCollection.add(nextItem);
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}
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}
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}
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}
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/**
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* Adds A3 document jobs to the collecting parameter according to some policy that can be whatever the client
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* (the print center) wants. The code is similar to the 'addA4Papers' method. The code can be changed to accommodate
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* the wants of the client.
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*
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* @param printerItemsCollection the collecting parameter
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*/
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public static void addA3Papers(Queue<PrinterItem> printerItemsCollection) {
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for (PrinterItem nextItem : printerQueue.getPrinterQueue()) {
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if (nextItem.paperSize.equals(PaperSizes.A3)) {
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// Encoding the policy into a Boolean: the A3 paper cannot be coloured and double-sided at the same time
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var isNotColouredAndSingleSided = !nextItem.isColour && !nextItem.isDoubleSided;
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if (isNotColouredAndSingleSided) {
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printerItemsCollection.add(nextItem);
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}
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}
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}
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}
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/**
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* Adds A2 document jobs to the collecting parameter according to some policy that can be whatever the client
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* (the print center) wants. The code is similar to the 'addA4Papers' method. The code can be changed to accommodate
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* the wants of the client.
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*
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* @param printerItemsCollection the collecting parameter
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*/
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public static void addA2Papers(Queue<PrinterItem> printerItemsCollection) {
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for (PrinterItem nextItem : printerQueue.getPrinterQueue()) {
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if (nextItem.paperSize.equals(PaperSizes.A2)) {
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// Encoding the policy into a Boolean: the A2 paper must be single page, single-sided, and non-coloured.
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var isNotColouredSingleSidedAndOnePage = nextItem.pageCount == 1 && !nextItem.isDoubleSided
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&& !nextItem.isColour;
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if (isNotColouredSingleSidedAndOnePage) {
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printerItemsCollection.add(nextItem);
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}
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}
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}
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}
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}
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```
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Each method takes a collecting parameter as an argument. It then adds elements, taken from a global variable,
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to this collecting parameter if each element satisfies a given criteria. These methods can have whatever policy the client desires.
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In this programmatic example, three print jobs are added to the queue. Only the first two print jobs should be added to
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the collecting parameter as per the policy. The elements of the `result` variable after execution are,
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| paperSize | pageCount | isDoubleSided | isColour |
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|-----------|-----------|---------------|----------|
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| A4 | 5 | false | false |
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| A3 | 2 | false | false |
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which is what we expected.
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## Class diagram
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## Applicability
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Use the Collecting Parameter design pattern when
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- you want to return a collection or object that is the collaborative result of several methods
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- You want to simplify a method that accumulates data as the original method is too complex
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## Tutorials
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Tutorials for this method are found in:
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- [Refactoring To Patterns](http://www.tarrani.net/RefactoringToPatterns.pdf) by Joshua Kerivsky
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- [Smalltalk Best Practice Patterns](https://ptgmedia.pearsoncmg.com/images/9780134769042/samplepages/013476904X.pdf) by Kent Beck
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## Known uses
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Joshua Kerivsky gives a real-world example in his book 'Refactoring to Patterns'. He gives an example of using the
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Collecting Parameter Design Pattern to create a `toString()` method for an XML tree. Without using this design pattern,
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this would require a bulky function with conditionals and concatenation that would worsen code readability. Such a method
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can be broken down into smaller methods, each appending their own set of information to the collecting parameter.
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See this in [Refactoring To Patterns](http://www.tarrani.net/RefactoringToPatterns.pdf).
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## Consequences
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Pros:
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- Makes code more readable
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- Avoids 'linkages', where numerous methods reference the same global variable
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- Increases maintainability by decomposing larger functions
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Cons:
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- May increase code length
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- Adds 'layers' of methods
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## Related patterns
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- [Compose Methods](https://www.geeksforgeeks.org/composite-design-pattern/)
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## Credits
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Following books were used:
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- [Refactoring To Patterns](http://www.tarrani.net/RefactoringToPatterns.pdf) by Joshua Kerivsky
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- [Smalltalk Best Practice Patterns](https://ptgmedia.pearsoncmg.com/images/9780134769042/samplepages/013476904X.pdf) by Kent Beck
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Sites:
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- [Wiki](https://wiki.c2.com/?CollectingParameter)
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|
After Width: | Height: | Size: 54 KiB |
@@ -0,0 +1,39 @@
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||||
@startuml
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||||
package com.iluwatar.collectingparameter {
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class App {
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~ printerQueue : PrinterQueue {static}
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+ App()
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+ addValidA2Papers(printerItemsCollection : Queue<PrinterItem>) {static}
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+ addValidA3Papers(printerItemsCollection : Queue<PrinterItem>) {static}
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+ addValidA4Papers(printerItemsCollection : Queue<PrinterItem>) {static}
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+ main(args : String[]) {static}
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}
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~enum PaperSizes {
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+ A2 {static}
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+ A3 {static}
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+ A4 {static}
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+ valueOf(name : String) : PaperSizes {static}
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+ values() : PaperSizes[] {static}
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}
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class PrinterItem {
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~ isColour : boolean
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~ isDoubleSided : boolean
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~ pageCount : int
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~ paperSize : PaperSizes
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+ PrinterItem(paperSize : PaperSizes, pageCount : int, isDoubleSided : boolean, isColour : boolean)
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}
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class PrinterQueue {
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~ currentInstance : PrinterQueue {static}
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- printerItemQueue : Queue<PrinterItem>
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- PrinterQueue()
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+ addPrinterItem(printerItem : PrinterItem)
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+ emptyQueue()
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+ getInstance() : PrinterQueue {static}
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+ getPrinterQueue() : Queue<PrinterItem>
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||||
}
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}
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PrinterQueue --> "-currentInstance" PrinterQueue
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PrinterQueue --> "-printerItemQueue" PrinterItem
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App --> "-printerQueue" PrinterQueue
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PrinterItem --> "-paperSize" PaperSizes
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@enduml
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||||
@@ -0,0 +1,67 @@
|
||||
<?xml version="1.0" encoding="UTF-8"?>
|
||||
<!--
|
||||
|
||||
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.
|
||||
|
||||
-->
|
||||
<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">
|
||||
<parent>
|
||||
<artifactId>java-design-patterns</artifactId>
|
||||
<groupId>com.iluwatar</groupId>
|
||||
<version>1.26.0-SNAPSHOT</version>
|
||||
</parent>
|
||||
<modelVersion>4.0.0</modelVersion>
|
||||
<artifactId>collecting-parameter</artifactId>
|
||||
<dependencies>
|
||||
<dependency>
|
||||
<groupId>org.junit.jupiter</groupId>
|
||||
<artifactId>junit-jupiter-engine</artifactId>
|
||||
<scope>test</scope>
|
||||
</dependency>
|
||||
<dependency>
|
||||
<groupId>junit</groupId>
|
||||
<artifactId>junit</artifactId>
|
||||
<scope>test</scope>
|
||||
</dependency>
|
||||
</dependencies>
|
||||
<build>
|
||||
<plugins>
|
||||
<plugin>
|
||||
<groupId>org.apache.maven.plugins</groupId>
|
||||
<artifactId>maven-assembly-plugin</artifactId>
|
||||
<executions>
|
||||
<execution>
|
||||
<configuration>
|
||||
<archive>
|
||||
<manifest>
|
||||
<mainClass>com.iluwatar.collectingparameter.App</mainClass>
|
||||
</manifest>
|
||||
</archive>
|
||||
</configuration>
|
||||
</execution>
|
||||
</executions>
|
||||
</plugin>
|
||||
</plugins>
|
||||
</build>
|
||||
</project>
|
||||
@@ -0,0 +1,138 @@
|
||||
/*
|
||||
* 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.collectingparameter;
|
||||
|
||||
import java.util.LinkedList;
|
||||
import java.util.Queue;
|
||||
|
||||
/**
|
||||
* The Collecting Parameter Design Pattern aims to return a result that is the collaborative result of several
|
||||
* methods. This design pattern uses a 'collecting parameter' that is passed to several functions, accumulating results
|
||||
* as it travels from method-to-method. This is different to the Composed Method design pattern, where a single
|
||||
* collection is modified via several methods.
|
||||
*
|
||||
* <p>This example is inspired by Kent Beck's example in his book, 'Smalltalk Best Practice Patterns'. The context for this
|
||||
* situation is that there is a single printer queue {@link PrinterQueue} that holds numerous print jobs
|
||||
* {@link PrinterItem} that must be distributed to various print centers.
|
||||
* Each print center has its own requirements and printing limitations. In this example, the following requirements are:
|
||||
* If an A4 document is coloured, it must also be single-sided. All other non-coloured A4 documents are accepted.
|
||||
* All A3 documents must be non-coloured and single sided. All A2 documents must be a single page, single sided, and
|
||||
* non-coloured.
|
||||
*
|
||||
* <p>A collecting parameter (the result variable) is used to filter the global printer queue so that it meets the
|
||||
* requirements for this centre,
|
||||
**/
|
||||
|
||||
public class App {
|
||||
static PrinterQueue printerQueue = PrinterQueue.getInstance();
|
||||
|
||||
/**
|
||||
* Program entry point.
|
||||
*
|
||||
* @param args command line args
|
||||
*/
|
||||
public static void main(String[] args) {
|
||||
/*
|
||||
Initialising the printer queue with jobs
|
||||
*/
|
||||
printerQueue.addPrinterItem(new PrinterItem(PaperSizes.A4, 5, false, false));
|
||||
printerQueue.addPrinterItem(new PrinterItem(PaperSizes.A3, 2, false, false));
|
||||
printerQueue.addPrinterItem(new PrinterItem(PaperSizes.A2, 5, false, false));
|
||||
|
||||
/*
|
||||
This variable is the collecting parameter, and will store the policy abiding print jobs.
|
||||
*/
|
||||
var result = new LinkedList<PrinterItem>();
|
||||
|
||||
/*
|
||||
Adding A4, A3, and A2 papers that obey the policy
|
||||
*/
|
||||
addValidA4Papers(result);
|
||||
addValidA3Papers(result);
|
||||
addValidA2Papers(result);
|
||||
}
|
||||
|
||||
/**
|
||||
* Adds A4 document jobs to the collecting parameter according to some policy that can be whatever the client
|
||||
* (the print center) wants.
|
||||
*
|
||||
* @param printerItemsCollection the collecting parameter
|
||||
*/
|
||||
public static void addValidA4Papers(Queue<PrinterItem> printerItemsCollection) {
|
||||
/*
|
||||
Iterate through the printer queue, and add A4 papers according to the correct policy to the collecting parameter,
|
||||
which is 'printerItemsCollection' in this case.
|
||||
*/
|
||||
for (PrinterItem nextItem : printerQueue.getPrinterQueue()) {
|
||||
if (nextItem.paperSize.equals(PaperSizes.A4)) {
|
||||
var isColouredAndSingleSided = nextItem.isColour && !nextItem.isDoubleSided;
|
||||
if (isColouredAndSingleSided || !nextItem.isColour) {
|
||||
printerItemsCollection.add(nextItem);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Adds A3 document jobs to the collecting parameter according to some policy that can be whatever the client
|
||||
* (the print center) wants. The code is similar to the 'addA4Papers' method. The code can be changed to accommodate
|
||||
* the wants of the client.
|
||||
*
|
||||
* @param printerItemsCollection the collecting parameter
|
||||
*/
|
||||
public static void addValidA3Papers(Queue<PrinterItem> printerItemsCollection) {
|
||||
for (PrinterItem nextItem : printerQueue.getPrinterQueue()) {
|
||||
if (nextItem.paperSize.equals(PaperSizes.A3)) {
|
||||
|
||||
// Encoding the policy into a Boolean: the A3 paper cannot be coloured and double-sided at the same time
|
||||
var isNotColouredAndSingleSided = !nextItem.isColour && !nextItem.isDoubleSided;
|
||||
if (isNotColouredAndSingleSided) {
|
||||
printerItemsCollection.add(nextItem);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Adds A2 document jobs to the collecting parameter according to some policy that can be whatever the client
|
||||
* (the print center) wants. The code is similar to the 'addA4Papers' method. The code can be changed to accommodate
|
||||
* the wants of the client.
|
||||
*
|
||||
* @param printerItemsCollection the collecting parameter
|
||||
*/
|
||||
public static void addValidA2Papers(Queue<PrinterItem> printerItemsCollection) {
|
||||
for (PrinterItem nextItem : printerQueue.getPrinterQueue()) {
|
||||
if (nextItem.paperSize.equals(PaperSizes.A2)) {
|
||||
|
||||
// Encoding the policy into a Boolean: the A2 paper must be single page, single-sided, and non-coloured.
|
||||
var isNotColouredSingleSidedAndOnePage = nextItem.pageCount == 1 && !nextItem.isDoubleSided
|
||||
&& !nextItem.isColour;
|
||||
if (isNotColouredSingleSidedAndOnePage) {
|
||||
printerItemsCollection.add(nextItem);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,7 @@
|
||||
package com.iluwatar.collectingparameter;
|
||||
|
||||
enum PaperSizes {
|
||||
A2,
|
||||
A3,
|
||||
A4
|
||||
}
|
||||
@@ -0,0 +1,34 @@
|
||||
package com.iluwatar.collectingparameter;
|
||||
|
||||
import java.util.Objects;
|
||||
|
||||
/**
|
||||
* This class represents a Print Item, that should be added to the queue.
|
||||
**/
|
||||
public class PrinterItem {
|
||||
PaperSizes paperSize;
|
||||
int pageCount;
|
||||
boolean isDoubleSided;
|
||||
boolean isColour;
|
||||
|
||||
/**
|
||||
* The {@link PrinterItem} constructor.
|
||||
**/
|
||||
public PrinterItem(PaperSizes paperSize, int pageCount, boolean isDoubleSided, boolean isColour) {
|
||||
if (!Objects.isNull(paperSize)) {
|
||||
this.paperSize = paperSize;
|
||||
} else {
|
||||
throw new IllegalArgumentException();
|
||||
}
|
||||
|
||||
if (pageCount > 0) {
|
||||
this.pageCount = pageCount;
|
||||
} else {
|
||||
throw new IllegalArgumentException();
|
||||
}
|
||||
|
||||
this.isColour = isColour;
|
||||
this.isDoubleSided = isDoubleSided;
|
||||
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,52 @@
|
||||
package com.iluwatar.collectingparameter;
|
||||
|
||||
import java.util.LinkedList;
|
||||
import java.util.Objects;
|
||||
import java.util.Queue;
|
||||
|
||||
/**
|
||||
* This class represents a singleton Printer Queue. It contains a queue that can be filled up with {@link PrinterItem}.
|
||||
**/
|
||||
public class PrinterQueue {
|
||||
|
||||
static PrinterQueue currentInstance = null;
|
||||
private final Queue<PrinterItem> printerItemQueue;
|
||||
|
||||
/**
|
||||
* This class is a singleton. The getInstance method will ensure that only one instance exists at a time.
|
||||
*/
|
||||
public static PrinterQueue getInstance() {
|
||||
if (Objects.isNull(currentInstance)) {
|
||||
currentInstance = new PrinterQueue();
|
||||
}
|
||||
return currentInstance;
|
||||
}
|
||||
|
||||
/**
|
||||
* Empty the printer queue.
|
||||
*/
|
||||
public void emptyQueue() {
|
||||
currentInstance.getPrinterQueue().clear();
|
||||
}
|
||||
|
||||
/**
|
||||
* Private constructor prevents instantiation, unless using the getInstance() method.
|
||||
*/
|
||||
private PrinterQueue() {
|
||||
printerItemQueue = new LinkedList<>();
|
||||
}
|
||||
|
||||
public Queue<PrinterItem> getPrinterQueue() {
|
||||
return currentInstance.printerItemQueue;
|
||||
}
|
||||
|
||||
/**
|
||||
* Adds a single print job to the queue.
|
||||
*
|
||||
* @param printerItem The printing job to be added to the queue
|
||||
*/
|
||||
public void addPrinterItem(PrinterItem printerItem) {
|
||||
currentInstance.getPrinterQueue().add(printerItem);
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,39 @@
|
||||
/*
|
||||
* 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.collectingparameter;
|
||||
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
|
||||
|
||||
class AppTest {
|
||||
/**
|
||||
* Checks whether {@link App} executes without throwing exception
|
||||
*/
|
||||
@Test
|
||||
void executesWithoutException() {
|
||||
assertDoesNotThrow(() -> App.main(new String[]{}));
|
||||
}
|
||||
}
|
||||
+55
@@ -0,0 +1,55 @@
|
||||
package com.iluwatar.collectingparameter;
|
||||
|
||||
import org.junit.jupiter.api.Assertions;
|
||||
import org.junit.jupiter.api.Test;
|
||||
import org.junit.jupiter.api.Timeout;
|
||||
|
||||
import java.util.LinkedList;
|
||||
import java.util.Queue;
|
||||
|
||||
class CollectingParameterTest {
|
||||
|
||||
@Test
|
||||
@Timeout(1000)
|
||||
void testCollectingParameter() {
|
||||
PrinterQueue printerQueue = PrinterQueue.getInstance();
|
||||
printerQueue.emptyQueue();
|
||||
|
||||
PrinterItem item1 = new PrinterItem(PaperSizes.A4, 1, false, true);
|
||||
PrinterItem item2 = new PrinterItem(PaperSizes.A4, 10, true, false);
|
||||
PrinterItem item3 = new PrinterItem(PaperSizes.A4, 4, true, true);
|
||||
PrinterItem item4 = new PrinterItem(PaperSizes.A3, 9, false, false);
|
||||
PrinterItem item5 = new PrinterItem(PaperSizes.A3, 3, true, true);
|
||||
PrinterItem item6 = new PrinterItem(PaperSizes.A3, 3, false, true);
|
||||
PrinterItem item7 = new PrinterItem(PaperSizes.A3, 3, true, false);
|
||||
PrinterItem item8 = new PrinterItem(PaperSizes.A2, 1, false, false);
|
||||
PrinterItem item9 = new PrinterItem(PaperSizes.A2, 2, false, false);
|
||||
PrinterItem item10 = new PrinterItem(PaperSizes.A2, 1, true, false);
|
||||
PrinterItem item11 = new PrinterItem(PaperSizes.A2, 1, false, true);
|
||||
|
||||
printerQueue.addPrinterItem(item1);
|
||||
printerQueue.addPrinterItem(item2);
|
||||
printerQueue.addPrinterItem(item3);
|
||||
printerQueue.addPrinterItem(item4);
|
||||
printerQueue.addPrinterItem(item5);
|
||||
printerQueue.addPrinterItem(item6);
|
||||
printerQueue.addPrinterItem(item7);
|
||||
printerQueue.addPrinterItem(item8);
|
||||
printerQueue.addPrinterItem(item9);
|
||||
printerQueue.addPrinterItem(item10);
|
||||
printerQueue.addPrinterItem(item11);
|
||||
|
||||
Queue<PrinterItem> result = new LinkedList<>();
|
||||
App.addValidA4Papers(result);
|
||||
App.addValidA3Papers(result);
|
||||
App.addValidA2Papers(result);
|
||||
|
||||
Queue<PrinterItem> testResult = new LinkedList<>();
|
||||
testResult.add(item1);
|
||||
testResult.add(item2);
|
||||
testResult.add(item4);
|
||||
testResult.add(item8);
|
||||
|
||||
Assertions.assertArrayEquals(testResult.toArray(), result.toArray());
|
||||
}
|
||||
}
|
||||
+34
@@ -0,0 +1,34 @@
|
||||
package com.iluwatar.collectingparameter;
|
||||
|
||||
import org.junit.jupiter.api.Assertions;
|
||||
import org.junit.jupiter.api.Test;
|
||||
import org.junit.jupiter.api.Timeout;
|
||||
|
||||
import java.util.LinkedList;
|
||||
import java.util.Queue;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.*;
|
||||
|
||||
class PrinterQueueTest {
|
||||
|
||||
@Test
|
||||
@Timeout(1000)
|
||||
void singletonTest() {
|
||||
PrinterQueue printerQueue1 = PrinterQueue.getInstance();
|
||||
PrinterQueue printerQueue2 = PrinterQueue.getInstance();
|
||||
assertSame(printerQueue1, printerQueue2);
|
||||
}
|
||||
|
||||
@Test()
|
||||
@Timeout(1000)
|
||||
void negativePageCount() throws IllegalArgumentException {
|
||||
Assertions.assertThrows(IllegalArgumentException.class, () -> new PrinterItem(PaperSizes.A4, -1, true, true));
|
||||
}
|
||||
|
||||
@Test()
|
||||
@Timeout(1000)
|
||||
void nullPageSize() throws IllegalArgumentException {
|
||||
Assertions.assertThrows(IllegalArgumentException.class, () -> new PrinterItem(null, 1, true, true));
|
||||
}
|
||||
|
||||
}
|
||||
Reference in New Issue
Block a user