iSharkFly-Docs
/
java-tutorials
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

BAEL-3596 - Asynchronous Method Calls in Java

This commit is contained in:
Anshul BANSAL 2020-01-01 16:00:57 +02:00
parent 0104b269fa
commit 9cd73de5cc
5 changed files with 323 additions and 84 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

107
java-async/pom.xml
View File

@ -1,37 +1,88 @@
<?xml version="1.0" encoding="UTF-8"?>
<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">
<modelVersion>4.0.0</modelVersion>
<artifactId>java-async</artifactId>
<version>0.1.0-SNAPSHOT</version>
<name>java-async</name>
<packaging>jar</packaging>
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">
<modelVersion>4.0.0</modelVersion>
<artifactId>java-async</artifactId>
<name>java-async</name>
<packaging>jar</packaging>
<version>1.0</version>
<parent>
<groupId>com.baeldung</groupId>
<artifactId>parent-java</artifactId>
<version>0.0.1-SNAPSHOT</version>
<relativePath>../parent-java</relativePath>
</parent>
<parent>
<groupId>com.baeldung</groupId>
<artifactId>parent-java</artifactId>
<version>0.0.1-SNAPSHOT</version>
<relativePath>../parent-java</relativePath>
</parent>
<dependencies>
<dependencies>
<dependency>
<groupId>com.jcabi</groupId>
<artifactId>jcabi-aspects</artifactId>
<version>0.22.6</version>
</dependency>
</dependencies>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjrt</artifactId>
<version>1.9.5</version>
<scope>runtime</scope>
</dependency>
<build>
<finalName>java-async</finalName>
<resources>
<resource>
<directory>src/main/resources</directory>
<filtering>true</filtering>
</resource>
</resources>
</build>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>28.1-jre</version>
</dependency>
<properties>
<decimal4j.version>1.0.3</decimal4j.version>
<assertj.version>3.6.1</assertj.version>
</properties>
<dependency>
<groupId>org.cactoos</groupId>
<artifactId>cactoos</artifactId>
<version>0.43</version>
</dependency>
<dependency>
<groupId>com.ea.async</groupId>
<artifactId>ea-async</artifactId>
<version>1.2.3</version>
</dependency>
</dependencies>
<build>
<finalName>java-async</finalName>
<resources>
<resource>
<directory>src/main/resources</directory>
<filtering>true</filtering>
</resource>
</resources>
<plugins>
<plugin>
<groupId>com.jcabi</groupId>
<artifactId>jcabi-maven-plugin</artifactId>
<version>0.14.1</version>
<executions>
<execution>
<goals>
<goal>ajc</goal>
</goals>
</execution>
</executions>
<dependencies>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjtools</artifactId>
<version>1.9.1</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.9.1</version>
</dependency>
</dependencies>
</plugin>
</plugins>
</build>
</project>

46
java-async/src/main/java/com/baeldung/async/Async.java
View File

@ -1,46 +0,0 @@
package com.baeldung.async;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
public class Async {
public static void main(String[] args) {
System.out.println("hello world!!");
try {
Future<String> completableFuture = calculateAsync();
String result = completableFuture.get();
System.out.println(result);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ExecutionException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
CompletableFuture.runAsync(() -> {
System.out.println("This is Async");
});
}
public static Future<String> calculateAsync() throws InterruptedException {
CompletableFuture<String> completableFuture = new CompletableFuture<>();
Executors.newCachedThreadPool().submit(() -> {
Thread.sleep(500);
completableFuture.complete("Hello");
return null;
});
return completableFuture;
}
}

57
java-async/src/main/java/com/baeldung/async/EAAsyncExample.java Normal file
View File

@ -0,0 +1,57 @@
package com.baeldung.async;
import static com.ea.async.Async.await;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import com.ea.async.Async;
public class EAAsyncExample {
static {
Async.init();
}
public static void main(String[] args) throws Exception {
usingCompletableFuture();
usingAsyncAwait();
}
public static void usingCompletableFuture() throws InterruptedException, ExecutionException, Exception {
CompletableFuture<Void> completableFuture = hello()
.thenComposeAsync(hello -> mergeWorld(hello))
.thenAcceptAsync(helloWorld -> print(helloWorld))
.exceptionally( throwable -> {
System.out.println(throwable.getCause());
return null;
});
completableFuture.get();
}
public static CompletableFuture<String> hello() {
CompletableFuture<String> completableFuture = CompletableFuture.supplyAsync(() -> "Hello");
return completableFuture;
}
public static CompletableFuture<String> mergeWorld(String s) {
CompletableFuture<String> completableFuture = CompletableFuture.supplyAsync(() -> {
return s + " World!";
});
return completableFuture;
}
public static void print(String str) {
CompletableFuture.runAsync(() -> System.out.println(str));
}
private static void usingAsyncAwait() {
try {
String hello = await(hello());
String helloWorld = await(mergeWorld(hello));
await(CompletableFuture.runAsync(() -> print(helloWorld)));
} catch (Exception e) {
e.printStackTrace();
}
}
}

186
java-async/src/main/java/com/baeldung/async/JavaAsync.java Normal file
View File

@ -0,0 +1,186 @@
package com.baeldung.async;
import static com.ea.async.Async.await;
import java.util.concurrent.Callable;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import com.google.common.util.concurrent.AsyncCallable;
import com.google.common.util.concurrent.Callables;
import com.google.common.util.concurrent.FutureCallback;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.ListeningExecutorService;
import com.google.common.util.concurrent.MoreExecutors;
import com.jcabi.aspects.Async;
import com.jcabi.aspects.Loggable;
public class JavaAsync {
static {
com.ea.async.Async.init();
}
private static final ExecutorService threadpool = Executors.newCachedThreadPool();
public static void main (String[] args) throws InterruptedException, ExecutionException {
int number = 20;
//Thread Example
factorialUsingThread(number).start();
//FutureTask Example
Future<Long> futureTask = factorialUsingFutureTask(number);
System.out.println("Factorial of " + number + " is: " + futureTask.get());
// CompletableFuture Example
Future<Long> completableFuture = factorialUsingCompletableFuture(number);
System.out.println("Factorial of " + number + " is: " + completableFuture.get());
// EA Async example
System.out.println("Factorial of " + number + " is: " + factorialUsingEAAsync(number));
// cactoos async example
Future<Long> asyncFuture = factorialUsingCactoos(number);
System.out.println("Factorial of " + number + " is: " + asyncFuture.get());
// Guava example
ListenableFuture<Long> guavaFuture = factorialUsingGuavaServiceSubmit(number);
System.out.println("Factorial of " + number + " is: " + guavaFuture.get());
ListenableFuture<Long> guavaFutures = factorialUsingGuavaFutures(number);
System.out.println("Factorial of " + number + " is: " + guavaFutures.get());
// @async jcabi-aspect example
Future<Long> aspectFuture = factorialUsingJcabiAspect(number);
System.out.println("Factorial of " + number + " is: " + aspectFuture.get());
}
/**
* Finds factorial of a number
* @param number
* @return
*/
public static long factorial(int number) {
long result = 1;
for(int i=number;i>0;i--) {
result *= i;
}
return result;
}
/**
* Finds factorial of a number using Thread
* @param number
* @return
*/
@Loggable
public static Thread factorialUsingThread(int number) {
Thread newThread = new Thread(() -> {
System.out.println("Factorial of " + number + " is: " + factorial(number));
});
return newThread;
}
/**
* Finds factorial of a number using FutureTask
* @param number
* @return
*/
@Loggable
public static Future<Long> factorialUsingFutureTask(int number) {
Future<Long> futureTask = threadpool.submit(() -> factorial(number));
while (!futureTask.isDone()) {
System.out.println("FutureTask is not finished yet...");
}
return futureTask;
}
/**
* Finds factorial of a number using CompletableFuture
* @param number
* @return
*/
@Loggable
public static Future<Long> factorialUsingCompletableFuture(int number) {
CompletableFuture<Long> completableFuture = CompletableFuture.supplyAsync(() -> factorial(number));
return completableFuture;
}
/**
* Finds factorial of a number using EA Async
* @param number
* @return
*/
@Loggable
public static long factorialUsingEAAsync(int number) {
CompletableFuture<Long> completableFuture = CompletableFuture.supplyAsync(() -> factorial(number));
long result = await(completableFuture);
return result;
}
/**
*
* Finds factorial of a number using Async of Cactoos
* @param number
* @return
* @throws InterruptedException
* @throws ExecutionException
*/
@Loggable
public static Future<Long> factorialUsingCactoos(int number) throws InterruptedException, ExecutionException {
org.cactoos.func.Async<Integer, Long> asyncFunction = new org.cactoos.func.Async<Integer, Long>(input -> factorial(input));
Future<Long> asyncFuture = asyncFunction.apply(number);
return asyncFuture;
}
/**
* Finds factorial of a number using Guava's ListeningExecutorService.submit()
* @param number
* @return
*/
@Loggable
public static ListenableFuture<Long> factorialUsingGuavaServiceSubmit(int number) {
ListeningExecutorService service = MoreExecutors.listeningDecorator(threadpool);
ListenableFuture<Long> factorialFuture = (ListenableFuture<Long>) service.submit(()-> factorial(number));
return factorialFuture;
}
/**
* Finds factorial of a number using Guava's Futures.submitAsync()
* @param number
* @return
*/
@Loggable
public static ListenableFuture<Long> factorialUsingGuavaFutures(int number) {
ListeningExecutorService service = MoreExecutors.listeningDecorator(threadpool);
AsyncCallable<Long> asyncCallable = Callables.asAsyncCallable(new Callable<Long>() {
public Long call() {
return factorial(number);
}
}, service);
return Futures.submitAsync(asyncCallable, service);
}
/**
*
* Finds factorial of a number using @Async of jcabi-aspects
* @param number
* @return
*/
@Async
@Loggable
public static Future<Long> factorialUsingJcabiAspect(int number) {
Future<Long> factorialFuture = CompletableFuture.supplyAsync(() -> factorial(number));
return factorialFuture;
}
}

9
java-async/src/main/resources/com/baeldung/async/AsyncUnitTest.java
View File

@ -1,9 +0,0 @@
package com.baeldung.async;
public class AsyncUnitTest {
public static void main(String[] args) {
System.out.println("hello");
}
}