Exemple Java pour l'utilisation de JMS avec les files d'attente Amazon SQS standard

Les exemples de code suivants montrent comment utiliser le service de messagerie Java (JMS) avec les files d'attente Amazon SQS standard. Pour plus d'informations sur l'utilisation des files d'attente FIFO, consultez Pour créer une file d'attente FIFO, Envoi de messages de façon synchrone et Réception des messages de façon synchrone. (La réception synchrone des messages est identique pour les files d'attente standard et FIFO. Toutefois, les messages des files d'attente FIFO contiennent davantage d'attributs.)

ExampleConfiguration.java

L'exemple de code Java SDK v 1.x suivant définit le nom de file d'attente par défaut, la région et les informations d'identification à utiliser avec les autres exemples Java.

/*
 * Copyright 2010-2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  https://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 *
 */

public class ExampleConfiguration {
    public static final String DEFAULT_QUEUE_NAME = "SQSJMSClientExampleQueue";
    
    public static final Region DEFAULT_REGION = Region.getRegion(Regions.US_EAST_2);
    
    private static String getParameter( String args[], int i ) {
        if( i + 1 >= args.length ) {
            throw new IllegalArgumentException( "Missing parameter for " + args[i] );
        }
        return args[i+1];
    }
    
    /**
     * Parse the command line and return the resulting config. If the config parsing fails
     * print the error and the usage message and then call System.exit
     * 
     * @param app the app to use when printing the usage string
     * @param args the command line arguments
     * @return the parsed config
     */
    public static ExampleConfiguration parseConfig(String app, String args[]) {
        try {
            return new ExampleConfiguration(args);
        } catch (IllegalArgumentException e) {
            System.err.println( "ERROR: " + e.getMessage() );
            System.err.println();
            System.err.println( "Usage: " + app + " [--queue <queue>] [--region <region>] [--credentials <credentials>] ");
            System.err.println( "  or" );
            System.err.println( "       " + app + " <spring.xml>" );
            System.exit(-1);
            return null;
        }
    }
    
    private ExampleConfiguration(String args[]) {
        for( int i = 0; i < args.length; ++i ) {
            String arg = args[i];
            if( arg.equals( "--queue" ) ) {
                setQueueName(getParameter(args, i));
                i++;
            } else if( arg.equals( "--region" ) ) {
                String regionName = getParameter(args, i);
                try {
                    setRegion(Region.getRegion(Regions.fromName(regionName)));
                } catch( IllegalArgumentException e ) {
                    throw new IllegalArgumentException( "Unrecognized region " + regionName );  
                }
                i++;
            } else if( arg.equals( "--credentials" ) ) {
                String credsFile = getParameter(args, i);
                try {
                    setCredentialsProvider( new PropertiesFileCredentialsProvider(credsFile) );
                } catch (AmazonClientException e) {
                    throw new IllegalArgumentException("Error reading credentials from " + credsFile, e );
                }
                i++;
            } else {
                throw new IllegalArgumentException("Unrecognized option " + arg);
            }
        }
    }
    
    private String queueName = DEFAULT_QUEUE_NAME;
    private Region region = DEFAULT_REGION;
    private AWSCredentialsProvider credentialsProvider = new DefaultAWSCredentialsProviderChain();
    
    public String getQueueName() {
        return queueName;
    }
    
    public void setQueueName(String queueName) {
        this.queueName = queueName;
    }
    
    public Region getRegion() {
        return region;
    }
    
    public void setRegion(Region region) {
        this.region = region;
    }
 
    public AWSCredentialsProvider getCredentialsProvider() {
        return credentialsProvider;
    }
    
    public void setCredentialsProvider(AWSCredentialsProvider credentialsProvider) {
        // Make sure they're usable first
        credentialsProvider.getCredentials();
        this.credentialsProvider = credentialsProvider;
    }
}

TextMessageSender.java

L'exemple de code Java suivant crée un producteur de messages texte.

/*
 * Copyright 2010-2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  https://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 *
 */

public class TextMessageSender {
    public static void main(String args[]) throws JMSException {
        ExampleConfiguration config = ExampleConfiguration.parseConfig("TextMessageSender", args);
        
        ExampleCommon.setupLogging();
        
        // Create the connection factory based on the config       
        SQSConnectionFactory connectionFactory = new SQSConnectionFactory(
                new ProviderConfiguration(),
                AmazonSQSClientBuilder.standard()
                        .withRegion(config.getRegion().getName())
                        .withCredentials(config.getCredentialsProvider())
                );
        
        // Create the connection
        SQSConnection connection = connectionFactory.createConnection();
        
        // Create the queue if needed
        ExampleCommon.ensureQueueExists(connection, config.getQueueName());
            
        // Create the session
        Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
        MessageProducer producer = session.createProducer( session.createQueue( config.getQueueName() ) );
        
        sendMessages(session, producer);
 
        // Close the connection. This closes the session automatically
        connection.close();
        System.out.println( "Connection closed" );
    }
 
    private static void sendMessages( Session session, MessageProducer producer ) {
        BufferedReader inputReader = new BufferedReader(
            new InputStreamReader( System.in, Charset.defaultCharset() ) );
        
        try {
            String input;
            while( true ) { 
                System.out.print( "Enter message to send (leave empty to exit): " );
                input = inputReader.readLine();
                if( input == null || input.equals("" ) ) break;
                
                TextMessage message = session.createTextMessage(input);
                producer.send(message);
                System.out.println( "Send message " + message.getJMSMessageID() );
            }
        } catch (EOFException e) {
            // Just return on EOF
        } catch (IOException e) {
            System.err.println( "Failed reading input: " + e.getMessage() );
        } catch (JMSException e) {
            System.err.println( "Failed sending message: " + e.getMessage() );
            e.printStackTrace();
        }
    }
}

SyncMessageReceiver.java

L'exemple de code Java suivant crée un consommateur de messages synchrone.

/*
 * Copyright 2010-2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  https://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 *
 */

public class SyncMessageReceiver {
public static void main(String args[]) throws JMSException {
    ExampleConfiguration config = ExampleConfiguration.parseConfig("SyncMessageReceiver", args);
    
    ExampleCommon.setupLogging();
    
    // Create the connection factory based on the config
    SQSConnectionFactory connectionFactory = new SQSConnectionFactory(
            new ProviderConfiguration(),
            AmazonSQSClientBuilder.standard()
                    .withRegion(config.getRegion().getName())
                    .withCredentials(config.getCredentialsProvider())
            );
    
    // Create the connection
    SQSConnection connection = connectionFactory.createConnection();
    
    // Create the queue if needed
    ExampleCommon.ensureQueueExists(connection, config.getQueueName());
        
    // Create the session
    Session session = connection.createSession(false, Session.CLIENT_ACKNOWLEDGE);
    MessageConsumer consumer = session.createConsumer( session.createQueue( config.getQueueName() ) );

    connection.start();
    
    receiveMessages(session, consumer);

    // Close the connection. This closes the session automatically
    connection.close();
    System.out.println( "Connection closed" );
}

private static void receiveMessages( Session session, MessageConsumer consumer ) {
    try {
        while( true ) {
            System.out.println( "Waiting for messages");
            // Wait 1 minute for a message
            Message message = consumer.receive(TimeUnit.MINUTES.toMillis(1));
            if( message == null ) {
                System.out.println( "Shutting down after 1 minute of silence" );
                break;
            }
            ExampleCommon.handleMessage(message);
            message.acknowledge();
            System.out.println( "Acknowledged message " + message.getJMSMessageID() );
        }
    } catch (JMSException e) {
        System.err.println( "Error receiving from SQS: " + e.getMessage() );
        e.printStackTrace();
    }
}
}

AsyncMessageReceiver.java

L'exemple de code Java suivant crée un consommateur de messages asynchrone.

/*
 * Copyright 2010-2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  https://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 *
 */

public class AsyncMessageReceiver {
    public static void main(String args[]) throws JMSException, InterruptedException {
        ExampleConfiguration config = ExampleConfiguration.parseConfig("AsyncMessageReceiver", args);
         
        ExampleCommon.setupLogging();          
         
        // Create the connection factory based on the config
        SQSConnectionFactory connectionFactory = new SQSConnectionFactory(
                new ProviderConfiguration(),
                AmazonSQSClientBuilder.standard()
                        .withRegion(config.getRegion().getName())
                        .withCredentials(config.getCredentialsProvider())
                );
         
        // Create the connection
        SQSConnection connection = connectionFactory.createConnection();
         
        // Create the queue if needed
        ExampleCommon.ensureQueueExists(connection, config.getQueueName());
             
        // Create the session
        Session session = connection.createSession(false, Session.CLIENT_ACKNOWLEDGE);
        MessageConsumer consumer = session.createConsumer( session.createQueue( config.getQueueName() ) );
         
        // No messages are processed until this is called
        connection.start();

        ReceiverCallback callback = new ReceiverCallback();
        consumer.setMessageListener( callback );
         
        callback.waitForOneMinuteOfSilence();
        System.out.println( "Returning after one minute of silence" );

        // Close the connection. This closes the session automatically
        connection.close();
        System.out.println( "Connection closed" );
    }
    
    
    private static class ReceiverCallback implements MessageListener {
        // Used to listen for message silence
        private volatile long timeOfLastMessage = System.nanoTime();
         
        public void waitForOneMinuteOfSilence() throws InterruptedException {
            for(;;) {
                long timeSinceLastMessage = System.nanoTime() - timeOfLastMessage;
                long remainingTillOneMinuteOfSilence = 
                    TimeUnit.MINUTES.toNanos(1) - timeSinceLastMessage;
                if( remainingTillOneMinuteOfSilence < 0 ) {
                    break;
                }
                TimeUnit.NANOSECONDS.sleep(remainingTillOneMinuteOfSilence);
            }
        }
         

        @Override
        public void onMessage(Message message) {
            try {
                ExampleCommon.handleMessage(message);
                message.acknowledge();
                System.out.println( "Acknowledged message " + message.getJMSMessageID() );
                timeOfLastMessage = System.nanoTime();
            } catch (JMSException e) {
                System.err.println( "Error processing message: " + e.getMessage() );
                e.printStackTrace();
            }
        }
    }
}

SyncMessageReceiverClientAcknowledge.java

L'exemple de code Java suivant crée un consommateur synchrone avec le mode de reconnaissance du client.

/*
 * Copyright 2010-2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  https://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 *
 */

/**
 * An example class to demonstrate the behavior of CLIENT_ACKNOWLEDGE mode for received messages. This example
 * complements the example given in {@link SyncMessageReceiverUnorderedAcknowledge} for UNORDERED_ACKNOWLEDGE mode.
 *
 * First, a session, a message producer, and a message consumer are created. Then, two messages are sent. Next, two messages
 * are received but only the second one is acknowledged. After waiting for the visibility time out period, an attempt to
 * receive another message is made. It's shown that no message is returned for this attempt since in CLIENT_ACKNOWLEDGE mode,
 * as expected, all the messages prior to the acknowledged messages are also acknowledged.
 *
 * This ISN'T the behavior for UNORDERED_ACKNOWLEDGE mode. Please see {@link SyncMessageReceiverUnorderedAcknowledge}
 * for an example.
 */
public class SyncMessageReceiverClientAcknowledge {
 
    // Visibility time-out for the queue. It must match to the one set for the queue for this example to work.
    private static final long TIME_OUT_SECONDS = 1;
 
    public static void main(String args[]) throws JMSException, InterruptedException {
        // Create the configuration for the example
        ExampleConfiguration config = ExampleConfiguration.parseConfig("SyncMessageReceiverClientAcknowledge", args);
 
        // Setup logging for the example
        ExampleCommon.setupLogging();
 
        // Create the connection factory based on the config
        SQSConnectionFactory connectionFactory = new SQSConnectionFactory(
                new ProviderConfiguration(),
                AmazonSQSClientBuilder.standard()
                        .withRegion(config.getRegion().getName())
                        .withCredentials(config.getCredentialsProvider())
                );
 
        // Create the connection
        SQSConnection connection = connectionFactory.createConnection();
 
        // Create the queue if needed
        ExampleCommon.ensureQueueExists(connection, config.getQueueName());
 
        // Create the session  with client acknowledge mode
        Session session = connection.createSession(false, Session.CLIENT_ACKNOWLEDGE);
 
        // Create the producer and consume
        MessageProducer producer = session.createProducer(session.createQueue(config.getQueueName()));
        MessageConsumer consumer = session.createConsumer(session.createQueue(config.getQueueName()));
 
        // Open the connection
        connection.start();
 
        // Send two text messages
        sendMessage(producer, session, "Message 1");
        sendMessage(producer, session, "Message 2");
 
        // Receive a message and don't acknowledge it
        receiveMessage(consumer, false);
 
        // Receive another message and acknowledge it
        receiveMessage(consumer, true);
 
        // Wait for the visibility time out, so that unacknowledged messages reappear in the queue
        System.out.println("Waiting for visibility timeout...");
        Thread.sleep(TimeUnit.SECONDS.toMillis(TIME_OUT_SECONDS));
 
        // Attempt to receive another message and acknowledge it. This results in receiving no messages since
        // we have acknowledged the second message. Although we didn't explicitly acknowledge the first message,
        // in the CLIENT_ACKNOWLEDGE mode, all the messages received prior to the explicitly acknowledged message
        // are also acknowledged. Therefore, we have implicitly acknowledged the first message.
        receiveMessage(consumer, true);
 
        // Close the connection. This closes the session automatically
        connection.close();
        System.out.println("Connection closed.");
    }
 
    /**
     * Sends a message through the producer.
     *
     * @param producer Message producer
     * @param session Session
     * @param messageText Text for the message to be sent
     * @throws JMSException
     */
    private static void sendMessage(MessageProducer producer, Session session, String messageText) throws JMSException {
        // Create a text message and send it
        producer.send(session.createTextMessage(messageText));
    }
 
    /**
     * Receives a message through the consumer synchronously with the default timeout (TIME_OUT_SECONDS).
     * If a message is received, the message is printed. If no message is received, "Queue is empty!" is
     * printed.
     *
     * @param consumer Message consumer
     * @param acknowledge If true and a message is received, the received message is acknowledged.
     * @throws JMSException
     */
    private static void receiveMessage(MessageConsumer consumer, boolean acknowledge) throws JMSException {
        // Receive a message
        Message message = consumer.receive(TimeUnit.SECONDS.toMillis(TIME_OUT_SECONDS));
 
        if (message == null) {
            System.out.println("Queue is empty!");
        } else {
            // Since this queue has only text messages, cast the message object and print the text
            System.out.println("Received: " + ((TextMessage) message).getText());
 
            // Acknowledge the message if asked
            if (acknowledge) message.acknowledge();
        }
    }
}

SyncMessageReceiverUnorderedAcknowledge.java

L'exemple de code Java suivant crée un consommateur synchrone avec le mode de reconnaissance sans ordre de réception.

/*
 * Copyright 2010-2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  https://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 *
 */

/**
 * An example class to demonstrate the behavior of UNORDERED_ACKNOWLEDGE mode for received messages. This example
 * complements the example given in {@link SyncMessageReceiverClientAcknowledge} for CLIENT_ACKNOWLEDGE mode.
 *
 * First, a session, a message producer, and a message consumer are created. Then, two messages are sent. Next, two messages
 * are received but only the second one is acknowledged. After waiting for the visibility time out period, an attempt to
 * receive another message is made. It's shown that the first message received in the prior attempt is returned again
 * for the second attempt. In UNORDERED_ACKNOWLEDGE mode, all the messages must be explicitly acknowledged no matter what
 * the order they're received.
 *
 * This ISN'T the behavior for CLIENT_ACKNOWLEDGE mode. Please see {@link SyncMessageReceiverClientAcknowledge}
 * for an example.
 */
public class SyncMessageReceiverUnorderedAcknowledge {
 
    // Visibility time-out for the queue. It must match to the one set for the queue for this example to work.
    private static final long TIME_OUT_SECONDS = 1;
 
    public static void main(String args[]) throws JMSException, InterruptedException {
        // Create the configuration for the example
        ExampleConfiguration config = ExampleConfiguration.parseConfig("SyncMessageReceiverUnorderedAcknowledge", args);
 
        // Setup logging for the example
        ExampleCommon.setupLogging();
 
        // Create the connection factory based on the config
        SQSConnectionFactory connectionFactory = new SQSConnectionFactory(
                new ProviderConfiguration(),
                AmazonSQSClientBuilder.standard()
                        .withRegion(config.getRegion().getName())
                        .withCredentials(config.getCredentialsProvider())
                );
 
        // Create the connection
        SQSConnection connection = connectionFactory.createConnection();
 
        // Create the queue if needed
        ExampleCommon.ensureQueueExists(connection, config.getQueueName());
 
        // Create the session  with unordered acknowledge mode
        Session session = connection.createSession(false, SQSSession.UNORDERED_ACKNOWLEDGE);
 
        // Create the producer and consume
        MessageProducer producer = session.createProducer(session.createQueue(config.getQueueName()));
        MessageConsumer consumer = session.createConsumer(session.createQueue(config.getQueueName()));
 
        // Open the connection
        connection.start();
 
        // Send two text messages
        sendMessage(producer, session, "Message 1");
        sendMessage(producer, session, "Message 2");
 
        // Receive a message and don't acknowledge it
        receiveMessage(consumer, false);
 
        // Receive another message and acknowledge it
        receiveMessage(consumer, true);
 
        // Wait for the visibility time out, so that unacknowledged messages reappear in the queue
        System.out.println("Waiting for visibility timeout...");
        Thread.sleep(TimeUnit.SECONDS.toMillis(TIME_OUT_SECONDS));
 
        // Attempt to receive another message and acknowledge it. This results in receiving the first message since
        // we have acknowledged only the second message. In the UNORDERED_ACKNOWLEDGE mode, all the messages must
        // be explicitly acknowledged.
        receiveMessage(consumer, true);
 
        // Close the connection. This closes the session automatically
        connection.close();
        System.out.println("Connection closed.");
    }
 
    /**
     * Sends a message through the producer.
     *
     * @param producer Message producer
     * @param session Session
     * @param messageText Text for the message to be sent
     * @throws JMSException
     */
    private static void sendMessage(MessageProducer producer, Session session, String messageText) throws JMSException {
        // Create a text message and send it
        producer.send(session.createTextMessage(messageText));
    }
 
    /**
     * Receives a message through the consumer synchronously with the default timeout (TIME_OUT_SECONDS).
     * If a message is received, the message is printed. If no message is received, "Queue is empty!" is
     * printed.
     *
     * @param consumer Message consumer
     * @param acknowledge If true and a message is received, the received message is acknowledged.
     * @throws JMSException
     */
    private static void receiveMessage(MessageConsumer consumer, boolean acknowledge) throws JMSException {
        // Receive a message
        Message message = consumer.receive(TimeUnit.SECONDS.toMillis(TIME_OUT_SECONDS));
 
        if (message == null) {
            System.out.println("Queue is empty!");
        } else {
            // Since this queue has only text messages, cast the message object and print the text
            System.out.println("Received: " + ((TextMessage) message).getText());
 
            // Acknowledge the message if asked
            if (acknowledge) message.acknowledge();
        }
    }
}

SpringExampleConfiguration.xml

L'exemple de code XML suivant est un fichier de configuration bean pour SpringExample.java.

<!--
    Copyright 2010-2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.

    Licensed under the Apache License, Version 2.0 (the "License").
    You may not use this file except in compliance with the License.
    A copy of the License is located at

    https://aws.amazon.com/apache2.0

    or in the "license" file accompanying this file. This file is distributed
    on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
    express or implied. See the License for the specific language governing
    permissions and limitations under the License.
-->

<?xml version="1.0" encoding="UTF-8"?>
<beans
    xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:util="http://www.springframework.org/schema/util"
    xmlns:p="http://www.springframework.org/schema/p"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd
    ">
    
    <bean id="CredentialsProviderBean" class="com.amazonaws.auth.DefaultAWSCredentialsProviderChain"/>
    
    <bean id="ClientBuilder" class="com.amazonaws.services.sqs.AmazonSQSClientBuilder" factory-method="standard">
        <property name="region" value="us-east-2"/>
        <property name="credentials" ref="CredentialsProviderBean"/>               
    </bean>
    
    <bean id="ProviderConfiguration" class="com.amazon.sqs.javamessaging.ProviderConfiguration">
        <property name="numberOfMessagesToPrefetch" value="5"/>
    </bean>
    
    <bean id="ConnectionFactory" class="com.amazon.sqs.javamessaging.SQSConnectionFactory">
        <constructor-arg ref="ProviderConfiguration" />
        <constructor-arg ref="ClientBuilder" />
    </bean>
    
    <bean id="Connection" class="javax.jms.Connection"
        factory-bean="ConnectionFactory"
        factory-method="createConnection"
        init-method="start"
        destroy-method="close" />
    
    <bean id="QueueName" class="java.lang.String">
        <constructor-arg value="SQSJMSClientExampleQueue"/>
    </bean>
</beans>

SpringExample.java

L'exemple de code Java suivant utilise le fichier de configuration bean pour initialiser vos objets.

/*
 * Copyright 2010-2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  https://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 *
 */
                
public class SpringExample {
    public static void main(String args[]) throws JMSException {
        if( args.length != 1 || !args[0].endsWith(".xml")) {
            System.err.println( "Usage: " + SpringExample.class.getName() + " <spring config.xml>" );
            System.exit(1);
        }
        
        File springFile = new File( args[0] );
        if( !springFile.exists() || !springFile.canRead() ) {
            System.err.println( "File " + args[0] + " doesn't exist or isn't readable.");
            System.exit(2);
        }
        
        ExampleCommon.setupLogging();
        
        FileSystemXmlApplicationContext context = 
            new FileSystemXmlApplicationContext( "file://" + springFile.getAbsolutePath() );
        
        Connection connection;
        try {
            connection = context.getBean(Connection.class);
        } catch( NoSuchBeanDefinitionException e ) {
            System.err.println( "Can't find the JMS connection to use: " + e.getMessage() );
            System.exit(3);
            return;
        }
        
        String queueName;
        try {
            queueName = context.getBean("QueueName", String.class);
        } catch( NoSuchBeanDefinitionException e ) {
            System.err.println( "Can't find the name of the queue to use: " + e.getMessage() );
            System.exit(3);
            return;
        }
        
        if( connection instanceof SQSConnection ) {
            ExampleCommon.ensureQueueExists( (SQSConnection) connection, queueName );
        }
        
        // Create the session
        Session session = connection.createSession(false, Session.CLIENT_ACKNOWLEDGE);
        MessageConsumer consumer = session.createConsumer( session.createQueue( queueName) );
        
        receiveMessages(session, consumer);
 
        // The context can be setup to close the connection for us
        context.close();
        System.out.println( "Context closed" );
    }
 
    private static void receiveMessages( Session session, MessageConsumer consumer ) {
        try {
            while( true ) {
                System.out.println( "Waiting for messages");
                // Wait 1 minute for a message
                Message message = consumer.receive(TimeUnit.MINUTES.toMillis(1));
                if( message == null ) {
                    System.out.println( "Shutting down after 1 minute of silence" );
                    break;
                }
                ExampleCommon.handleMessage(message);
                message.acknowledge();
                System.out.println( "Acknowledged message" );
            }
        } catch (JMSException e) {
            System.err.println( "Error receiving from SQS: " + e.getMessage() );
            e.printStackTrace();
        }
    }
}

ExampleCommon.java

L'exemple de code Java suivant vérifie s'il existe une file d'attente Amazon SQS, puis en crée une si ce n'est pas le cas. Il comprend également un exemple de code de journalisation.

/*
 * Copyright 2010-2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  https://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 *
 */

public class ExampleCommon {
    /**
     * A utility function to check the queue exists and create it if needed. For most  
     * use cases this is usually done by an administrator before the application is run. 
     */
    public static void ensureQueueExists(SQSConnection connection, String queueName) throws JMSException {
        AmazonSQSMessagingClientWrapper client = connection.getWrappedAmazonSQSClient();
        
        /**
         * In most cases, you can do this with just a createQueue call, but GetQueueUrl 
         * (called by queueExists) is a faster operation for the common case where the queue 
         * already exists. Also many users and roles have permission to call GetQueueUrl
         * but don't have permission to call CreateQueue.
         */
        if( !client.queueExists(queueName) ) {
            client.createQueue( queueName );
        }
    }
 
    public static void setupLogging() {
        // Setup logging
        BasicConfigurator.configure();
        Logger.getRootLogger().setLevel(Level.WARN);
    }
 
    public static void handleMessage(Message message) throws JMSException {
        System.out.println( "Got message " + message.getJMSMessageID() );
        System.out.println( "Content: ");
        if( message instanceof TextMessage ) {
            TextMessage txtMessage = ( TextMessage ) message;
            System.out.println( "\t" + txtMessage.getText() );
        } else if( message instanceof BytesMessage ){
            BytesMessage byteMessage = ( BytesMessage ) message;
            // Assume the length fits in an int - SQS only supports sizes up to 256k so that
            // should be true
            byte[] bytes = new byte[(int)byteMessage.getBodyLength()];
            byteMessage.readBytes(bytes);
            System.out.println( "\t" +  Base64.encodeAsString( bytes ) );
        } else if( message instanceof ObjectMessage ) {
            ObjectMessage objMessage = (ObjectMessage) message;
            System.out.println( "\t" + objMessage.getObject() );
        }
    }
}