本文介绍如何使用Java SDK中的Sample,完成创建队列、发送消息、接收和删除消息、以及删除队列。
步骤一:准备工作
- 下载最新版Java SDK,解压到aliyun-sdk-mns-samples文件夹。
- 用Eclipse导入Maven工程,选择aliyun-sdk-mns-samples文件夹。
- 在用户目录中创建.aliyun-mns.properties文件,并填写服务地址、AccessKeyId和AccessKeySecret。
说明 Linux系统的用户目录为/home/YOURNAME/,Windows系统的用户目录为C:\Users\YOURNAME。
- AccessKeyId、AccessKeySecret
- 访问阿里云API的密钥对。
- 如果使用阿里云账号访问,请登录AccessKey管理页面创建和查看。
- 如果使用RAM用户访问,请登录阿里云访问控制控制台查看。
- Endpoint
- AccessKeyId、AccessKeySecret
步骤二:创建队列
创建队列的代码段如下。
public class CreateQueueDemo {
public static void main(String[] args) {
CloudAccount account = new CloudAccount(
ServiceSettings.getMNSAccessKeyId(),
ServiceSettings.getMNSAccessKeySecret(),
ServiceSettings.getMNSAccountEndpoint());
MNSClient client = account.getMNSClient();
try
{
QueueMeta qMeta = new QueueMeta();
qMeta.setQueueName("queue-demo");
qMeta.setPollingWaitSeconds(30);
CloudQueue cQueue = client.createQueue(qMeta);
System.out.println("Create queue successfully. URL: " + cQueue.getQueueURL());
} catch (ClientException ce)
{
System.out.println("Something wrong with the network connection between client and MNS service."
+ "Please check your network and DNS availability.");
ce.printStackTrace();
} catch (ServiceException se)
{
if (se.getErrorCode().equals("QueueNotExist"))
{
System.out.println("Queue is not exist.Please create before use");
} else if (se.getErrorCode().equals("TimeExpired"))
{
System.out.println("The request is time expired. Please check your local machine timeclock");
}
se.printStackTrace();
} catch (Exception e)
{
System.out.println("Unknown exception happened!");
e.printStackTrace();
}
client.close();
}
}
步骤三:发送消息
创建队列后,即可向队列发送消息。
public class ProducerDemo {
public static void main(String[] args) {
CloudAccount account = new CloudAccount(
ServiceSettings.getMNSAccessKeyId(),
ServiceSettings.getMNSAccessKeySecret(),
ServiceSettings.getMNSAccountEndpoint());
MNSClient client = account.getMNSClient();
try{
CloudQueue queue = client.getQueueRef("queue-demo");
for (int i = 0; i < 10; i++)
{
Message message = new Message();
message.setMessageBody("demo_message_body" + i);
Message putMsg = queue.putMessage(message);
System.out.println("Send message id is: " + putMsg.getMessageId());
}
} catch (ClientException ce)
{
System.out.println("Something wrong with the network connection between client and MNS service."
+ "Please check your network and DNS availability.");
ce.printStackTrace();
} catch (ServiceException se)
{
if (se.getErrorCode().equals("QueueNotExist"))
{
System.out.println("Queue is not exist.Please create before use");
} else if (se.getErrorCode().equals("TimeExpired"))
{
System.out.println("The request is time expired. Please check your local machine timeclock");
}
se.printStackTrace();
} catch (Exception e)
{
System.out.println("Unknown exception happened!");
e.printStackTrace();
}
client.close();
}
}
步骤四:接收和删除消息
向队列发送消息后,从队列中取出并删除该条消息。
public class ConsumerDemo {
public static void main(String[] args) {
CloudAccount account = new CloudAccount(
ServiceSettings.getMNSAccessKeyId(),
ServiceSettings.getMNSAccessKeySecret(),
ServiceSettings.getMNSAccountEndpoint());
MNSClient client = account.getMNSClient();
try{
CloudQueue queue = client.getQueueRef("queue-demo");
for (int i = 0; i < 10; i++)
{
Message popMsg = queue.popMessage();
if (popMsg != null){
System.out.println("message handle: " + popMsg.getReceiptHandle());
System.out.println("message body: " + popMsg.getMessageBodyAsString());
System.out.println("message id: " + popMsg.getMessageId());
System.out.println("message dequeue count:" + popMsg.getDequeueCount());
queue.deleteMessage(popMsg.getReceiptHandle());
System.out.println("delete message successfully.\n");
}
}
} catch (ClientException ce)
{
System.out.println("Something wrong with the network connection between client and MNS service."
+ "Please check your network and DNS availability.");
ce.printStackTrace();
} catch (ServiceException se)
{
if (se.getErrorCode().equals("QueueNotExist"))
{
System.out.println("Queue is not exist.Please create queue before use");
} else if (se.getErrorCode().equals("TimeExpired"))
{
System.out.println("The request is time expired. Please check your local machine timeclock");
}
se.printStackTrace();
} catch (Exception e)
{
System.out.println("Unknown exception happened!");
e.printStackTrace();
}
client.close();
}
}
步骤五:删除队列
删除测试用的队列。
public class DeleteQueueDemo {
public static void main(String[] args) {
CloudAccount account = new CloudAccount(
ServiceSettings.getMNSAccessKeyId(),
ServiceSettings.getMNSAccessKeySecret(),
ServiceSettings.getMNSAccountEndpoint());
MNSClient client = account.getMNSClient();
try
{
CloudQueue queue = client.getQueueRef("queue-demo");
queue.delete();
System.out.println("Delete cloud-queue-demo successfully!");
} catch (ClientException ce)
{
System.out.println("Something wrong with the network connection between client and MNS service."
+ "Please check your network and DNS availability.");
ce.printStackTrace();
} catch (ServiceException se)
{
if (se.getErrorCode().equals("QueueNotExist"))
{
System.out.println("Queue is not exist.Please create before use");
} else if (se.getErrorCode().equals("TimeExpired"))
{
System.out.println("The request is time expired. Please check your local machine timeclock");
}
se.printStackTrace();
} catch (Exception e)
{
System.out.println("Unknown exception happened!");
e.printStackTrace();
}
client.close();
}
}