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Work on #403, added class diagrams and javadocs

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This commit is contained in:
Narendra Pathai
2016-07-22 18:34:05 +05:30
parent eb560f5f54
commit 09ba5ca656
7 changed files with 344 additions and 3 deletions
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promise/etc/promise.ucls Normal file
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@@ -0,0 +1,115 @@
<?xml version="1.0" encoding="UTF-8"?>
<class-diagram version="1.1.10" icons="true" automaticImage="PNG" 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.promise.Promise" project="promise"
file="/promise/src/main/java/com/iluwatar/promise/Promise.java" binary="false" corner="BOTTOM_RIGHT">
<position height="-1" width="-1" x="524" y="541"/>
<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="false" static="true"/>
<operations public="true" package="false" protected="true" private="false" static="true"/>
</display>
</class>
<interface id="2" language="java" name="java.util.concurrent.Future" project="async-method-invocation"
file="/usr/lib/java/jdk1.8.0_45/jre/lib/rt.jar" binary="true" corner="BOTTOM_RIGHT">
<position height="-1" width="-1" x="527" y="94"/>
<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="com.iluwatar.promise.PromiseSupport" project="promise"
file="/promise/src/main/java/com/iluwatar/promise/PromiseSupport.java" binary="false" corner="BOTTOM_RIGHT">
<position height="-1" width="-1" x="524" y="313"/>
<display autosize="true" stereotype="true" package="true" initial-value="false" signature="true"
sort-features="false" accessors="true" visibility="true">
<attributes public="true" package="false" protected="true" private="true" static="true"/>
<operations public="true" package="false" protected="true" private="true" static="true"/>
</display>
</class>
<interface id="4" language="java" name="java.util.concurrent.Executor" project="async-method-invocation"
file="/usr/lib/java/jdk1.8.0_45/jre/lib/rt.jar" binary="true" corner="BOTTOM_RIGHT">
<position height="-1" width="-1" x="834" y="573"/>
<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>
<interface id="5" language="java" name="java.util.concurrent.Callable" project="async-method-invocation"
file="/usr/lib/java/jdk1.8.0_45/jre/lib/rt.jar" binary="true" corner="BOTTOM_RIGHT">
<position height="-1" width="-1" x="825" y="433"/>
<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>
<interface id="6" language="java" name="java.util.function.Consumer" project="async-method-invocation"
file="/usr/lib/java/jdk1.8.0_45/jre/lib/rt.jar" binary="true" corner="BOTTOM_RIGHT">
<position height="-1" width="-1" x="162" y="437"/>
<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="false" static="true"/>
</display>
</interface>
<interface id="7" language="java" name="java.util.function.Function" project="async-method-invocation"
file="/usr/lib/java/jdk1.8.0_45/jre/lib/rt.jar" binary="true" corner="BOTTOM_RIGHT">
<position height="-1" width="-1" x="168" y="591"/>
<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="false" static="false"/>
</display>
</interface>
<class id="8" language="java" name="com.iluwatar.promise.App" project="promise"
file="/promise/src/main/java/com/iluwatar/promise/App.java" binary="false" corner="BOTTOM_RIGHT">
<position height="-1" width="-1" x="992" y="206"/>
<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="false" static="true"/>
</display>
</class>
<realization id="9">
<end type="SOURCE" refId="3"/>
<end type="TARGET" refId="2"/>
</realization>
<dependency id="10">
<end type="SOURCE" refId="8"/>
<end type="TARGET" refId="1"/>
</dependency>
<generalization id="11">
<end type="SOURCE" refId="1"/>
<end type="TARGET" refId="3"/>
</generalization>
<dependency id="12">
<end type="SOURCE" refId="1"/>
<end type="TARGET" refId="4"/>
</dependency>
<dependency id="13">
<end type="SOURCE" refId="1"/>
<end type="TARGET" refId="7"/>
</dependency>
<dependency id="14">
<end type="SOURCE" refId="8"/>
<end type="TARGET" refId="4"/>
</dependency>
<dependency id="15">
<end type="SOURCE" refId="1"/>
<end type="TARGET" refId="6"/>
</dependency>
<dependency id="16">
<end type="SOURCE" refId="1"/>
<end type="TARGET" refId="5"/>
</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>

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promise/src/main/java/com/iluwatar/promise/App.java
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@@ -1,5 +1,28 @@
/**
* The MIT License
* Copyright (c) 2014 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.promise;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
@@ -7,14 +30,31 @@ import java.util.concurrent.Executors;
/**
*
* Application that uses promise pattern.
* <p>The Promise object is used for asynchronous computations. A Promise represents an operation that
* hasn't completed yet, but is expected in the future.
*
* <p>A Promise represents a proxy for a value not necessarily known when the promise is created. It
* allows you to associate dependent promises to an asynchronous action's eventual success value or
* failure reason. This lets asynchronous methods return values like synchronous methods: instead of the final
* value, the asynchronous method returns a promise of having a value at some point in the future.
*
* <p>Promises provide a few advantages over callback objects:
* <ul>
* <li> Functional composition and error handling
* <li> Prevents callback hell and provides callback aggregation
* </ul>
*
* @see CompletableFuture
*/
public class App {
private App() {
}
/**
* Program entry point
* @param args arguments
* @throws InterruptedException if main thread is interruped.
* @throws InterruptedException if main thread is interrupted.
* @throws ExecutionException if an execution error occurs.
*/
public static void main(String[] args) throws InterruptedException, ExecutionException {

25
promise/src/main/java/com/iluwatar/promise/Promise.java
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@@ -1,3 +1,25 @@
/**
* The MIT License
* Copyright (c) 2014 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.promise;
import java.util.concurrent.Callable;
@@ -8,6 +30,7 @@ import java.util.function.Function;
/**
* Implements the promise pattern.
*
* @param <T> type of result.
*/
public class Promise<T> extends PromiseSupport<T> {
@@ -41,7 +64,7 @@ public class Promise<T> extends PromiseSupport<T> {
postFulfillment();
}
void postFulfillment() {
private void postFulfillment() {
if (fulfillmentAction == null) {
return;
}

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promise/src/main/java/com/iluwatar/promise/PromiseSupport.java Normal file
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@@ -0,0 +1,119 @@
/**
* The MIT License
* Copyright (c) 2014 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.promise;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
/**
* A really simplified implementation of future that allows completing it successfully with a value
* or exceptionally with an exception.
*/
class PromiseSupport<T> implements Future<T> {
static final int RUNNING = 1;
static final int FAILED = 2;
static final int COMPLETED = 3;
final Object lock;
volatile int state = RUNNING;
T value;
Exception exception;
PromiseSupport() {
this.lock = new Object();
}
void fulfill(T value) {
this.value = value;
this.state = COMPLETED;
synchronized (lock) {
lock.notifyAll();
}
}
void fulfillExceptionally(Exception exception) {
this.exception = exception;
this.state = FAILED;
synchronized (lock) {
lock.notifyAll();
}
}
@Override
public boolean cancel(boolean mayInterruptIfRunning) {
return false;
}
@Override
public boolean isCancelled() {
return false;
}
@Override
public boolean isDone() {
return state > RUNNING;
}
@Override
public T get() throws InterruptedException, ExecutionException {
if (state == COMPLETED) {
return value;
} else if (state == FAILED) {
throw new ExecutionException(exception);
} else {
synchronized (lock) {
lock.wait();
if (state == COMPLETED) {
return value;
} else {
throw new ExecutionException(exception);
}
}
}
}
@Override
public T get(long timeout, TimeUnit unit)
throws InterruptedException, ExecutionException, TimeoutException {
if (state == COMPLETED) {
return value;
} else if (state == FAILED) {
throw new ExecutionException(exception);
} else {
synchronized (lock) {
lock.wait(unit.toMillis(timeout));
if (state == COMPLETED) {
return value;
} else if (state == FAILED) {
throw new ExecutionException(exception);
} else {
throw new TimeoutException();
}
}
}
}
}

22
promise/src/test/java/com/iluwatar/promise/AppTest.java
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@@ -1,3 +1,25 @@
/**
* The MIT License
* Copyright (c) 2014 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.promise;
import java.util.concurrent.ExecutionException;

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promise/src/test/java/com/iluwatar/promise/PromiseTest.java
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@@ -1,3 +1,25 @@
/**
* The MIT License
* Copyright (c) 2014 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.promise;
import static org.junit.Assert.assertEquals;