在 SpringBoot 中，@JmsListener 如何以及何时被调用？
In SpringBoot how & when does @JmsListener gets called?
我是 SpringBoot 的新手。尝试构建一个简单的非 Web 进程，我在其中监听 MQ 队列并处理收到的消息。我尝试了各种方法来在 SB 中实现这一点，但不幸的是我无法调用 @JmsListener 方法。也没有错误，进程只是等待。
所有 MQ 队列详细信息都在 application.properties
中
我确实验证了队列中有消息，我可以使用旧的 MQ 接收器方式检索它们。
我想知道@JmsListener Annotation 方法是如何以及何时被调用的？我确实尝试创建一个 JmsListenerContainerFactory 并将其包含在注释参数中，但没有任何区别。
很少有类似的例子，它看起来很简单，但我就是无法让它工作。任何建议表示赞赏。谢谢
主SpringBootClass
@SpringBootApplication
@EnableJms
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
MQListener Class
@Component
public class MQListener {
@JmsListener(destination = "${mq.queueName}")
public void receiveMessage(final Message message) throws JMSException{
System.out.println("...Message Received...");
String messageData = null;
if(message instanceof TextMessage) {
TextMessage textMessage = (TextMessage)message;
messageData = textMessage.getText();
}
}
}
MQ配置Class
@Configuration
public class MQConfiguration {
@Value("${mq.host}")
private String host;
@Value("${mq.port}")
private Integer port;
@Value("${mq.queue-manager}")
private String queueManager;
@Value("${mq.channel}")
private String channel;
@Value("{mq.queueName}")
private String queueName;
@Value("${mq.receive-timeout}")
private long receiveTimeout;
@Bean
public MQQueueConnectionFactory mqQueueConnectionFactory() {
MQQueueConnectionFactory mqQueueConnectionFactory = new MQQueueConnectionFactory();
mqQueueConnectionFactory.setHostName(host);
try {
mqQueueConnectionFactory.setTransportType(WMQConstants.WMQ_CM_CLIENT);
mqQueueConnectionFactory.setChannel(channel);
mqQueueConnectionFactory.setPort(port);
mqQueueConnectionFactory.setQueueManager(queueManager);
} catch (Exception e) {
e.printStackTrace();
}
return mqQueueConnectionFactory;
}
}
当您使用 MQ 连接工厂的默认设置时，您实际上并不需要它。相反，您可以使用 Spring Boot 将为您创建的默认值。您也只需要一条短信，这样您就可以让 Spring 进行编组。在这种情况下，您所需要的只是从该示例派生的消息使用者 - https://github.com/ibm-messaging/mq-dev-patterns/tree/master/Spring-JMS/src/main/java/com/ibm/mq/samples/jms/spring/level101
package ...
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.jms.annotation.JmsListener;
import org.springframework.stereotype.Component;
@Component
public class MessageConsumer101 {
protected final Log logger = LogFactory.getLog(getClass());
@JmsListener(destination = "${mq.queueName}")
public void receive(String message) {
logger.info("");
logger.info( this.getClass().getSimpleName());
logger.info("Received message is: " + message);
}
}
您将让 Spring 引导创建 MQ 容器，您需要在 application.properties 中以 -
的形式提供设置
# MQ Connection settings
ibm.mq.queueManager=QM1
ibm.mq.channel=DEV.APP.SVRCONN
ibm.mq.connName=localhost(1414)
# Change the following lines as necessary. Set the ibm.mq.user
# property to an empty string to send no authentication request.
ibm.mq.user=app
ibm.mq.password=passw0rd
与自定义连接工厂相比，您更可能需要自定义侦听器，但如果您确实想要配置不同于默认设置的 ConnectionFactory，请使用从该示例派生的配置和消息使用者 - https://github.com/ibm-messaging/mq-dev-patterns/tree/master/Spring-JMS/src/main/java/com/ibm/mq/samples/jms/spring/level114
配置，只需要设置偏离默认的属性即可。
package ...
import com.ibm.mq.jms.MQConnectionFactory;
import com.ibm.mq.samples.jms.spring.globals.handlers.OurDestinationResolver;
import com.ibm.mq.samples.jms.spring.globals.handlers.OurMessageConverter;
import com.ibm.mq.spring.boot.MQConfigurationProperties;
import com.ibm.mq.spring.boot.MQConnectionFactoryFactory;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jms.config.DefaultJmsListenerContainerFactory;
import org.springframework.jms.config.JmsListenerContainerFactory;
import org.springframework.jms.core.JmsTemplate;
import org.springframework.jms.support.QosSettings;
import javax.jms.DeliveryMode;
import javax.jms.JMSException;
@Configuration
public class MQConfiguration114 {
protected final Log logger = LogFactory.getLog(getClass());
@Bean
public MQConnectionFactory mqConnectionFactory() throws JMSException {
MQConfigurationProperties properties = new MQConfigurationProperties();
// Properties will be a mix of defaults, and those found in application.properties
// under ibm.mq
// Here we can override any of the properties should we need to
MQConnectionFactoryFactory mqcff = new MQConnectionFactoryFactory(properties,null);
MQConnectionFactory mqcf = mqcff.createConnectionFactory(MQConnectionFactory.class);
return mqcf;
}
@Bean
public JmsListenerContainerFactory<?> myContainerFactory114() throws JMSException {
DefaultJmsListenerContainerFactory factory = new DefaultJmsListenerContainerFactory();
factory.setConnectionFactory(mqConnectionFactory());
factory.setPubSubDomain(false);
factory.setMessageConverter(new OurMessageConverter());
factory.setDestinationResolver(new OurDestinationResolver());
// reply Qos
QosSettings rQos = new QosSettings();
rQos.setPriority(2);
rQos.setTimeToLive(10000);
rQos.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
factory.setReplyQosSettings(rQos);
return factory;
}
@Bean("myNonJmsTemplate114")
public JmsTemplate myNonJmsTemplate114() throws JMSException {
JmsTemplate jmsTemplate = new JmsTemplate(mqConnectionFactory());
jmsTemplate.setDestinationResolver(new OurDestinationResolver());
jmsTemplate.setMessageConverter(new OurMessageConverter());
return jmsTemplate;
}
注：监听器容器工厂基于自定义的连接工厂。你需要这一步。您的消息使用者看起来像：
package ...
import com.ibm.mq.samples.jms.spring.globals.data.OurData;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.jms.annotation.JmsListener;
import org.springframework.stereotype.Component;
@Component
public class MessageConsumer114 {
protected final Log logger = LogFactory.getLog(getClass());
@JmsListener(destination = "${mq.queueName}", containerFactory = "myContainerFactory114")
public void receiveRequest(OurData message) {
logger.info("");
logger.info( this.getClass().getSimpleName());
logger.info("Received message of type: " + message.getClass().getSimpleName());
logger.info("Received message :" + message);
}
}
如果您需要从 JMSMessage 对象执行您自己的编组，则使用从该示例派生的消息使用者（您只需要一个使用者，不需要其他）- https://github.com/ibm-messaging/mq-dev-patterns/tree/master/Spring-JMS/src/main/java/com/ibm/mq/samples/jms/spring/level105
package ...
import javax.jms.*;
import com.ibm.mq.samples.jms.spring.globals.Constants;
import com.ibm.mq.samples.jms.spring.globals.data.OurData;
import com.ibm.mq.samples.jms.spring.globals.data.OurOtherData;
import com.ibm.mq.samples.jms.spring.globals.utils.MessageUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.jms.annotation.JmsListener;
import org.springframework.stereotype.Component;
import java.io.Serializable;
@Component
public class MessageConsumer105 {
protected final Log logger = LogFactory.getLog(getClass());
@JmsListener(destination = "${app.l105.queue.name2}")
public void receiveData(Message message) {
logger.info("");
logger.info( this.getClass().getSimpleName());
logger.info("Received message of type: " + message.getClass().getSimpleName());
if (null != message) {
MessageUtils.checkMessageType(message);
}
}
}
在哪里
package ...
import com.ibm.mq.samples.jms.spring.globals.Constants;
import com.ibm.mq.samples.jms.spring.globals.data.OurData;
import com.ibm.mq.samples.jms.spring.globals.data.OurOtherData;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import javax.jms.*;
import java.io.Serializable;
import java.util.Map;
public class MessageUtils {
protected static final Log logger = LogFactory.getLog(MessageUtils.class);
private MessageUtils () {}
public static void checkMessageType(Message message) {
try {
if (message instanceof TextMessage) {
logger.info("Message matches TextMessage");
logger.info("message payload is " + ((TextMessage) message).getText());
} else if (message instanceof BytesMessage) {
logger.info("Message matches BytesMessage");
} else if (message instanceof MapMessage) {
logger.info("Message matches MapMessage");
} else if (message instanceof StreamMessage) {
logger.info("Message matches StreamMessage");
} else if (message instanceof ObjectMessage) {
checkForObject((ObjectMessage) message);
}
} catch (JMSException e) {
logger.warn("Unable to process JMS message");
}
}
public static void logHeaders(Map<String, Object> msgHeaders) {
if (! msgHeaders.isEmpty() ) {
logger.info("");
logger.info("Headers found");
msgHeaders.forEach((k, v) -> {
logger.info(k + ": is of type" + v.getClass());
});
}
}
private static void checkForObject(ObjectMessage message) {
try {
int typeValue = message.getIntProperty(Constants.DATATYPE);
if (Constants.DataTypes.OURDATATYPE.getValue() == typeValue) {
logger.info("It is one of our objects");
Serializable serObj = message.getObject();
OurData data = (OurData) serObj;
logger.info(data);
} else if (Constants.DataTypes.OUROTHERDATATYPE.getValue() == typeValue) {
logger.info("It is one of our other objects");
Serializable serObj = message.getObject();
OurOtherData data = (OurOtherData) serObj;
logger.info(data);
} else {
logger.warn("It is not one of our objects");
}
} catch (JMSException e) {
logger.warn("Unable to retrieve message data");
} catch (ClassCastException e2) {
logger.warn("Not the object we were expecting");
}
}
}
如果您的消费者和配置 类 有 @Component 和 @Configuration 注释并且位于同一个包系列中，那么它们将被找到，如果没有那么您需要添加为应用程序添加一些注释，让 Spring 接收它们。例如
package ...
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.jms.annotation.EnableJms;
@SpringBootApplication
@EnableJms
@ComponentScan
@EnableAutoConfiguration
public class MQApplication {
public static void main(String[] args) {
SpringApplication.run(MQApplication.class, args);
}
}
如果你没有
spring.jms.listener.auto-startup=false
在您的 application.properties 文件中，所有侦听器将在应用程序启动时自动启动。
您需要将 mq-jms-spring-boot-starter 命名为依赖项。例如。如果使用 Maven :
<dependency>
<groupId>com.ibm.mq</groupId>
<artifactId>mq-jms-spring-boot-starter</artifactId>
<version>2.4.1</version>
</dependency>
如果这是唯一的 JMS 实现者，那么 Spring Boot 将能够确定您的所有侦听器都在使用 IBM MQ。如果您将其他 JMS 提供程序列为依赖项，则 Spring 需要明确告知要使用哪个连接工厂。在 https://github.com/ibm-messaging/mq-dev-patterns/blob/master/Spring-JMS/pom.xml
处有一个样本 pom.xml，样本中只有所需的依赖项
尝试 https://github.com/ibm-messaging/mq-dev-patterns/tree/master/Spring-JMS 处的 101 样本
它基于 Maven，仅在其 pom.xml 中列出了所需的依赖项，您需要做的就是更新 https://github.com/ibm-messaging/mq-dev-patterns/tree/master/Spring-JMS/src/main/resources 中的 application.properties 以指向您的 MQ 服务器。
我是 SpringBoot 的新手。尝试构建一个简单的非 Web 进程，我在其中监听 MQ 队列并处理收到的消息。我尝试了各种方法来在 SB 中实现这一点，但不幸的是我无法调用 @JmsListener 方法。也没有错误，进程只是等待。
所有 MQ 队列详细信息都在 application.properties
中我确实验证了队列中有消息，我可以使用旧的 MQ 接收器方式检索它们。
我想知道@JmsListener Annotation 方法是如何以及何时被调用的？我确实尝试创建一个 JmsListenerContainerFactory 并将其包含在注释参数中，但没有任何区别。
很少有类似的例子，它看起来很简单，但我就是无法让它工作。任何建议表示赞赏。谢谢
主SpringBootClass
@SpringBootApplication
@EnableJms
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
MQListener Class
@Component
public class MQListener {
@JmsListener(destination = "${mq.queueName}")
public void receiveMessage(final Message message) throws JMSException{
System.out.println("...Message Received...");
String messageData = null;
if(message instanceof TextMessage) {
TextMessage textMessage = (TextMessage)message;
messageData = textMessage.getText();
}
}
}
MQ配置Class
@Configuration
public class MQConfiguration {
@Value("${mq.host}")
private String host;
@Value("${mq.port}")
private Integer port;
@Value("${mq.queue-manager}")
private String queueManager;
@Value("${mq.channel}")
private String channel;
@Value("{mq.queueName}")
private String queueName;
@Value("${mq.receive-timeout}")
private long receiveTimeout;
@Bean
public MQQueueConnectionFactory mqQueueConnectionFactory() {
MQQueueConnectionFactory mqQueueConnectionFactory = new MQQueueConnectionFactory();
mqQueueConnectionFactory.setHostName(host);
try {
mqQueueConnectionFactory.setTransportType(WMQConstants.WMQ_CM_CLIENT);
mqQueueConnectionFactory.setChannel(channel);
mqQueueConnectionFactory.setPort(port);
mqQueueConnectionFactory.setQueueManager(queueManager);
} catch (Exception e) {
e.printStackTrace();
}
return mqQueueConnectionFactory;
}
}
当您使用 MQ 连接工厂的默认设置时，您实际上并不需要它。相反，您可以使用 Spring Boot 将为您创建的默认值。您也只需要一条短信，这样您就可以让 Spring 进行编组。在这种情况下，您所需要的只是从该示例派生的消息使用者 - https://github.com/ibm-messaging/mq-dev-patterns/tree/master/Spring-JMS/src/main/java/com/ibm/mq/samples/jms/spring/level101
package ...
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.jms.annotation.JmsListener;
import org.springframework.stereotype.Component;
@Component
public class MessageConsumer101 {
protected final Log logger = LogFactory.getLog(getClass());
@JmsListener(destination = "${mq.queueName}")
public void receive(String message) {
logger.info("");
logger.info( this.getClass().getSimpleName());
logger.info("Received message is: " + message);
}
}
您将让 Spring 引导创建 MQ 容器，您需要在 application.properties 中以 -
# MQ Connection settings
ibm.mq.queueManager=QM1
ibm.mq.channel=DEV.APP.SVRCONN
ibm.mq.connName=localhost(1414)
# Change the following lines as necessary. Set the ibm.mq.user
# property to an empty string to send no authentication request.
ibm.mq.user=app
ibm.mq.password=passw0rd
与自定义连接工厂相比，您更可能需要自定义侦听器，但如果您确实想要配置不同于默认设置的 ConnectionFactory，请使用从该示例派生的配置和消息使用者 - https://github.com/ibm-messaging/mq-dev-patterns/tree/master/Spring-JMS/src/main/java/com/ibm/mq/samples/jms/spring/level114
配置，只需要设置偏离默认的属性即可。
package ...
import com.ibm.mq.jms.MQConnectionFactory;
import com.ibm.mq.samples.jms.spring.globals.handlers.OurDestinationResolver;
import com.ibm.mq.samples.jms.spring.globals.handlers.OurMessageConverter;
import com.ibm.mq.spring.boot.MQConfigurationProperties;
import com.ibm.mq.spring.boot.MQConnectionFactoryFactory;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jms.config.DefaultJmsListenerContainerFactory;
import org.springframework.jms.config.JmsListenerContainerFactory;
import org.springframework.jms.core.JmsTemplate;
import org.springframework.jms.support.QosSettings;
import javax.jms.DeliveryMode;
import javax.jms.JMSException;
@Configuration
public class MQConfiguration114 {
protected final Log logger = LogFactory.getLog(getClass());
@Bean
public MQConnectionFactory mqConnectionFactory() throws JMSException {
MQConfigurationProperties properties = new MQConfigurationProperties();
// Properties will be a mix of defaults, and those found in application.properties
// under ibm.mq
// Here we can override any of the properties should we need to
MQConnectionFactoryFactory mqcff = new MQConnectionFactoryFactory(properties,null);
MQConnectionFactory mqcf = mqcff.createConnectionFactory(MQConnectionFactory.class);
return mqcf;
}
@Bean
public JmsListenerContainerFactory<?> myContainerFactory114() throws JMSException {
DefaultJmsListenerContainerFactory factory = new DefaultJmsListenerContainerFactory();
factory.setConnectionFactory(mqConnectionFactory());
factory.setPubSubDomain(false);
factory.setMessageConverter(new OurMessageConverter());
factory.setDestinationResolver(new OurDestinationResolver());
// reply Qos
QosSettings rQos = new QosSettings();
rQos.setPriority(2);
rQos.setTimeToLive(10000);
rQos.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
factory.setReplyQosSettings(rQos);
return factory;
}
@Bean("myNonJmsTemplate114")
public JmsTemplate myNonJmsTemplate114() throws JMSException {
JmsTemplate jmsTemplate = new JmsTemplate(mqConnectionFactory());
jmsTemplate.setDestinationResolver(new OurDestinationResolver());
jmsTemplate.setMessageConverter(new OurMessageConverter());
return jmsTemplate;
}
注：监听器容器工厂基于自定义的连接工厂。你需要这一步。您的消息使用者看起来像：
package ...
import com.ibm.mq.samples.jms.spring.globals.data.OurData;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.jms.annotation.JmsListener;
import org.springframework.stereotype.Component;
@Component
public class MessageConsumer114 {
protected final Log logger = LogFactory.getLog(getClass());
@JmsListener(destination = "${mq.queueName}", containerFactory = "myContainerFactory114")
public void receiveRequest(OurData message) {
logger.info("");
logger.info( this.getClass().getSimpleName());
logger.info("Received message of type: " + message.getClass().getSimpleName());
logger.info("Received message :" + message);
}
}
如果您需要从 JMSMessage 对象执行您自己的编组，则使用从该示例派生的消息使用者（您只需要一个使用者，不需要其他）- https://github.com/ibm-messaging/mq-dev-patterns/tree/master/Spring-JMS/src/main/java/com/ibm/mq/samples/jms/spring/level105
package ...
import javax.jms.*;
import com.ibm.mq.samples.jms.spring.globals.Constants;
import com.ibm.mq.samples.jms.spring.globals.data.OurData;
import com.ibm.mq.samples.jms.spring.globals.data.OurOtherData;
import com.ibm.mq.samples.jms.spring.globals.utils.MessageUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.jms.annotation.JmsListener;
import org.springframework.stereotype.Component;
import java.io.Serializable;
@Component
public class MessageConsumer105 {
protected final Log logger = LogFactory.getLog(getClass());
@JmsListener(destination = "${app.l105.queue.name2}")
public void receiveData(Message message) {
logger.info("");
logger.info( this.getClass().getSimpleName());
logger.info("Received message of type: " + message.getClass().getSimpleName());
if (null != message) {
MessageUtils.checkMessageType(message);
}
}
}
在哪里
package ...
import com.ibm.mq.samples.jms.spring.globals.Constants;
import com.ibm.mq.samples.jms.spring.globals.data.OurData;
import com.ibm.mq.samples.jms.spring.globals.data.OurOtherData;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import javax.jms.*;
import java.io.Serializable;
import java.util.Map;
public class MessageUtils {
protected static final Log logger = LogFactory.getLog(MessageUtils.class);
private MessageUtils () {}
public static void checkMessageType(Message message) {
try {
if (message instanceof TextMessage) {
logger.info("Message matches TextMessage");
logger.info("message payload is " + ((TextMessage) message).getText());
} else if (message instanceof BytesMessage) {
logger.info("Message matches BytesMessage");
} else if (message instanceof MapMessage) {
logger.info("Message matches MapMessage");
} else if (message instanceof StreamMessage) {
logger.info("Message matches StreamMessage");
} else if (message instanceof ObjectMessage) {
checkForObject((ObjectMessage) message);
}
} catch (JMSException e) {
logger.warn("Unable to process JMS message");
}
}
public static void logHeaders(Map<String, Object> msgHeaders) {
if (! msgHeaders.isEmpty() ) {
logger.info("");
logger.info("Headers found");
msgHeaders.forEach((k, v) -> {
logger.info(k + ": is of type" + v.getClass());
});
}
}
private static void checkForObject(ObjectMessage message) {
try {
int typeValue = message.getIntProperty(Constants.DATATYPE);
if (Constants.DataTypes.OURDATATYPE.getValue() == typeValue) {
logger.info("It is one of our objects");
Serializable serObj = message.getObject();
OurData data = (OurData) serObj;
logger.info(data);
} else if (Constants.DataTypes.OUROTHERDATATYPE.getValue() == typeValue) {
logger.info("It is one of our other objects");
Serializable serObj = message.getObject();
OurOtherData data = (OurOtherData) serObj;
logger.info(data);
} else {
logger.warn("It is not one of our objects");
}
} catch (JMSException e) {
logger.warn("Unable to retrieve message data");
} catch (ClassCastException e2) {
logger.warn("Not the object we were expecting");
}
}
}
如果您的消费者和配置 类 有 @Component 和 @Configuration 注释并且位于同一个包系列中，那么它们将被找到，如果没有那么您需要添加为应用程序添加一些注释，让 Spring 接收它们。例如
package ...
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.jms.annotation.EnableJms;
@SpringBootApplication
@EnableJms
@ComponentScan
@EnableAutoConfiguration
public class MQApplication {
public static void main(String[] args) {
SpringApplication.run(MQApplication.class, args);
}
}
如果你没有
spring.jms.listener.auto-startup=false
在您的 application.properties 文件中，所有侦听器将在应用程序启动时自动启动。
您需要将 mq-jms-spring-boot-starter 命名为依赖项。例如。如果使用 Maven :
<dependency>
<groupId>com.ibm.mq</groupId>
<artifactId>mq-jms-spring-boot-starter</artifactId>
<version>2.4.1</version>
</dependency>
如果这是唯一的 JMS 实现者，那么 Spring Boot 将能够确定您的所有侦听器都在使用 IBM MQ。如果您将其他 JMS 提供程序列为依赖项，则 Spring 需要明确告知要使用哪个连接工厂。在 https://github.com/ibm-messaging/mq-dev-patterns/blob/master/Spring-JMS/pom.xml
处有一个样本 pom.xml，样本中只有所需的依赖项尝试 https://github.com/ibm-messaging/mq-dev-patterns/tree/master/Spring-JMS 处的 101 样本
它基于 Maven，仅在其 pom.xml 中列出了所需的依赖项，您需要做的就是更新 https://github.com/ibm-messaging/mq-dev-patterns/tree/master/Spring-JMS/src/main/resources 中的 application.properties 以指向您的 MQ 服务器。