Spring Boot集成Java DSL的實現代碼

這篇文章主要介紹了Spring Boot集成Java DSL的實現代碼,文中通過示例代碼介紹的非常詳細,對大家的學習或者工作具有一定的參考學習價值,需要的朋友們下面隨着小編來一起學習學習吧

Spring Integration Java DSL已經融合到Spring Integration Core 5.0,這是一個聰明而明顯的舉動,因爲:

  • 基於Java Config啓動新Spring項目的每個人都使用它
  • SI Java DSL使您可以使用Lambdas等新的強大Java 8功能
  • 您可以使用 基於IntegrationFlowBuilderBuilder模式構建流

讓我們看看基於ActiveMQ JMS的示例如何使用它。

Maven依賴:

<dependencies>
  <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-activemq</artifactId>
  </dependency>

  <dependency>
    <groupId>org.springframework.integration</groupId>
    <artifactId>spring-integration-core</artifactId>
  </dependency>

  <dependency>
    <groupId>org.springframework.integration</groupId>
    <artifactId>spring-integration-jms</artifactId>
  </dependency>

  <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-test</artifactId>
    <scope>test</scope>
  </dependency>

  <dependency>
    <groupId>org.apache.activemq</groupId>
    <artifactId>activemq-kahadb-store</artifactId>
  </dependency>

  <!-- https://mvnrepository.com/artifact/org.springframework.integration/spring-integration-java-dsl -->
  <dependency>
    <groupId>org.springframework.integration</groupId>
    <artifactId>spring-integration-java-dsl</artifactId>
    <version>1.2.3.RELEASE</version>
  </dependency>
</dependencies>

示例1:Jms入站網關

我們有以下ServiceActivator

@Service
public class ActiveMQEndpoint {
  @ServiceActivator(inputChannel = "inboundChannel")
  public void processMessage(final String inboundPayload) {
    System.out.println("Inbound message: "+inboundPayload);
  }
}

如果您想使用SI Java DSL 將inboundPayload從Jms隊列發送到Gateway風格的激活器,那麼請使用DSLJms工廠:

@Bean
public DynamicDestinationResolver dynamicDestinationResolver() {
  return new DynamicDestinationResolver();
}

@Bean
public ActiveMQConnectionFactory connectionFactory() {
  return new ActiveMQConnectionFactory();
}

@Bean
public DefaultMessageListenerContainer listenerContainer() {
  final DefaultMessageListenerContainer defaultMessageListenerContainer = new DefaultMessageListenerContainer();
  defaultMessageListenerContainer.setDestinationResolver(dynamicDestinationResolver());
  defaultMessageListenerContainer.setConnectionFactory(connectionFactory());
  defaultMessageListenerContainer.setDestinationName("jms.activeMQ.Test");
  return defaultMessageListenerContainer;
}

@Bean
public MessageChannel inboundChannel() {
  return MessageChannels.direct("inboundChannel").get();
}

@Bean
public JmsInboundGateway dataEndpoint() {
  return Jms.inboundGateway(listenerContainer())
      .requestChannel(inboundChannel()).get();
}

通過dataEndpoint bean 返回JmsInboundGatewaySpec,您還可以向SI通道或Jms目標發送回覆。查看文檔。

示例2:Jms消息驅動的通道適配器

如果您正在尋找替換消息驅動通道適配器的XML JMS配置,那麼JmsMessageDrivenChannelAdapter是一種適合您的方式:

@Bean
public DynamicDestinationResolver dynamicDestinationResolver() {
  return new DynamicDestinationResolver();
}

@Bean
public ActiveMQConnectionFactory connectionFactory() {
  return new ActiveMQConnectionFactory();
}

@Bean
public DefaultMessageListenerContainer listenerContainer() {
  final DefaultMessageListenerContainer defaultMessageListenerContainer = new DefaultMessageListenerContainer();
  defaultMessageListenerContainer.setDestinationResolver(dynamicDestinationResolver());
  defaultMessageListenerContainer.setConnectionFactory(connectionFactory());
  defaultMessageListenerContainer.setDestinationName("jms.activeMQ.Test");
  return defaultMessageListenerContainer;
}

@Bean
public MessageChannel inboundChannel() {
  return MessageChannels.direct("inboundChannel").get();
}

@Bean
public JmsMessageDrivenChannelAdapter dataEndpoint() {
  final ChannelPublishingJmsMessageListener channelPublishingJmsMessageListener =
      new ChannelPublishingJmsMessageListener();
  channelPublishingJmsMessageListener.setExpectReply(false);
  final JmsMessageDrivenChannelAdapter messageDrivenChannelAdapter = new
      JmsMessageDrivenChannelAdapter(listenerContainer(), channelPublishingJmsMessageListener
      );

  messageDrivenChannelAdapter.setOutputChannel(inboundChannel());
  return messageDrivenChannelAdapter;
}

與前面的示例一樣,入站有效負載如樣本1中一樣發送給激活器。

示例3:使用JAXB的Jms消息驅動的通道適配器

在典型的場景中,您希望通過Jms接受XML作爲文本消息,將其轉換爲JAXB存根並在服務激活器中處理它。我將向您展示如何使用SI Java DSL執行此操作,但首先讓我們爲xml處理添加兩個依賴項:

<dependency>
    <groupId>org.springframework.integration</groupId>
    <artifactId>spring-integration-xml</artifactId>
  </dependency>

  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-oxm</artifactId>
  </dependency>

我們將通過JMS接受shiporders ,所以首先XSD命名爲shiporder.xsd:

<?xml version="1.0" encoding="UTF-8" ?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">

  <xs:element name="shiporder">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="orderperson" type="xs:string"/>
        <xs:element name="shipto">
          <xs:complexType>
            <xs:sequence>
              <xs:element name="name" type="xs:string"/>
              <xs:element name="address" type="xs:string"/>
              <xs:element name="city" type="xs:string"/>
              <xs:element name="country" type="xs:string"/>
            </xs:sequence>
          </xs:complexType>
        </xs:element>
        <xs:element name="item" maxOccurs="unbounded">
          <xs:complexType>
            <xs:sequence>
              <xs:element name="title" type="xs:string"/>
              <xs:element name="note" type="xs:string" minOccurs="0"/>
              <xs:element name="quantity" type="xs:positiveInteger"/>
              <xs:element name="price" type="xs:decimal"/>
            </xs:sequence>
          </xs:complexType>
        </xs:element>
      </xs:sequence>
      <xs:attribute name="orderid" type="xs:string" use="required"/>
    </xs:complexType>
  </xs:element>

</xs:schema>

新增JAXB maven plugin 生成JAXB存根:

 <plugin>
      <groupId>org.codehaus.mojo</groupId>
      <artifactId>jaxb2-maven-plugin</artifactId>
      <version>2.3.1</version>
      <executions>
        <execution>
          <id>xjc-schema1</id>
          <goals>
            <goal>xjc</goal>
          </goals>
          <configuration>
            <!-- Use all XSDs under the west directory for sources here. -->
            <sources>
              <source>src/main/resources/xsds/shiporder.xsd</source>
            </sources>

            <!-- Package name of the generated sources. -->
            <packageName>com.example.stubs</packageName>
            <outputDirectory>src/main/java</outputDirectory>
            <clearOutputDir>false</clearOutputDir>
          </configuration>
        </execution>
      </executions>
    </plugin>

我們已經準備好了存根類和一切,現在使用Jaxb magic的Java DSL JMS消息驅動適配器:

/**
 * Sample 3: Jms message driven adapter with JAXB
 */
@Bean
public JmsMessageDrivenChannelAdapter dataEndpoint() {
  final ChannelPublishingJmsMessageListener channelPublishingJmsMessageListener =
      new ChannelPublishingJmsMessageListener();
  channelPublishingJmsMessageListener.setExpectReply(false);
  channelPublishingJmsMessageListener.setMessageConverter(new MarshallingMessageConverter(shipOrdersMarshaller()));
  final JmsMessageDrivenChannelAdapter messageDrivenChannelAdapter = new
      JmsMessageDrivenChannelAdapter(listenerContainer(), channelPublishingJmsMessageListener
  );

  messageDrivenChannelAdapter.setOutputChannel(inboundChannel());
  return messageDrivenChannelAdapter;
}

@Bean
public Jaxb2Marshaller shipOrdersMarshaller() {
  Jaxb2Marshaller marshaller = new Jaxb2Marshaller();
  marshaller.setContextPath("com.example.stubs");
  return marshaller;
}

XML配置在Java中使用它可以爲您提供如此強大的功能和靈活性。要完成此示例,inboundChannel的服務激活器將如下所示:

/**
 * Sample 3
 * @param shiporder
 */
@ServiceActivator(inputChannel = "inboundChannel")
public void processMessage(final Shiporder shiporder) {
  System.out.println(shiporder.getOrderid());
  System.out.println(shiporder.getOrderperson());
}

要測試流,您可以使用以下XML通過JConsole發送到JMS隊列:

 <?xml version="1.0" encoding="UTF-8"?>    
  <shiporder orderid="889923"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:noNamespaceSchemaLocation="shiporder.xsd">
   <orderperson>John Smith</orderperson>
    <shipto>
     <name>Ola Nordmann</name>
     <address>Langgt 23</address>
     <city>4000 Stavanger</city>
     <country>Norway</country>
    </shipto>
    <item>
     <title>Empire Burlesque</title>
     <note>Special Edition</note>
     <quantity>1</quantity>
     <price>10.90</price>
     </item>
    <item>
     <title>Hide your heart</title>
     <quantity>1</quantity>
     <price>9.90</price>
    </item>
  </shiporder>

示例4:具有JAXB和有效負載根路由的Jms消息驅動的通道適配器

另一種典型情況是接受XML作爲JMS文本消息,將其轉換爲JAXB存根並根據有效負載根類型將有效負載路由到某個服務激活器。當然SI Java DSL支持所有類型的路由,我將向您展示如何根據有效載荷類型進行路由。

首先,將以下XSD添加到shiporder.xsd所在的文件夾中,並將其命名爲purchaseorder.xsd:

<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
      xmlns:tns="http://tempuri.org/PurchaseOrderSchema.xsd"
      targetNamespace="http://tempuri.org/PurchaseOrderSchema.xsd"
      elementFormDefault="qualified">
  <xsd:element name="PurchaseOrder">
    <xsd:complexType>
      <xsd:sequence>
        <xsd:element name="ShipTo" type="tns:USAddress" maxOccurs="2"/>
        <xsd:element name="BillTo" type="tns:USAddress"/>
      </xsd:sequence>
      <xsd:attribute name="OrderDate" type="xsd:date"/>
    </xsd:complexType>
  </xsd:element>

  <xsd:complexType name="USAddress">
    <xsd:sequence>
      <xsd:element name="name"  type="xsd:string"/>
      <xsd:element name="street" type="xsd:string"/>
      <xsd:element name="city"  type="xsd:string"/>
      <xsd:element name="state" type="xsd:string"/>
      <xsd:element name="zip"  type="xsd:integer"/>
    </xsd:sequence>
    <xsd:attribute name="country" type="xsd:NMTOKEN" fixed="US"/>
  </xsd:complexType>
</xsd:schema>

然後添加到jaxb maven插件配置:

 <plugin>
      <groupId>org.codehaus.mojo</groupId>
      <artifactId>jaxb2-maven-plugin</artifactId>
      <version>2.3.1</version>
      <executions>
        <execution>
          <id>xjc-schema1</id>
          <goals>
            <goal>xjc</goal>
          </goals>
          <configuration>
            <!-- Use all XSDs under the west directory for sources here. -->
            <sources>
              <source>src/main/resources/xsds/shiporder.xsd</source>
              <source>src/main/resources/xsds/purchaseorder.xsd</source>
            </sources>

            <!-- Package name of the generated sources. -->
            <packageName>com.example.stubs</packageName>
            <outputDirectory>src/main/java</outputDirectory>
            <clearOutputDir>false</clearOutputDir>
          </configuration>
        </execution>
      </executions>
    </plugin>

運行mvn clean install以生成新XSD的JAXB存根。現在承諾有效負載根映射:

@Bean
public Jaxb2Marshaller ordersMarshaller() {
  Jaxb2Marshaller marshaller = new Jaxb2Marshaller();
  marshaller.setContextPath("com.example.stubs");
  return marshaller;
}

/**
 * Sample 4: Jms message driven adapter with Jaxb and Payload routing.
 * @return
 */
@Bean
public JmsMessageDrivenChannelAdapter dataEndpoint() {
  final ChannelPublishingJmsMessageListener channelPublishingJmsMessageListener =
      new ChannelPublishingJmsMessageListener();
  channelPublishingJmsMessageListener.setMessageConverter(new MarshallingMessageConverter(ordersMarshaller()));
  final JmsMessageDrivenChannelAdapter messageDrivenChannelAdapter = new
      JmsMessageDrivenChannelAdapter(listenerContainer(), channelPublishingJmsMessageListener
  );

  messageDrivenChannelAdapter.setOutputChannel(inboundChannel());
  return messageDrivenChannelAdapter;
}

@Bean
public IntegrationFlow payloadRootMapping() {
  return IntegrationFlows.from(inboundChannel()).<Object, Class<?>>route(Object::getClass, m->m
      .subFlowMapping(Shiporder.class, sf->sf.handle((MessageHandler) message -> {
        final Shiporder shiporder = (Shiporder) message.getPayload();
        System.out.println(shiporder.getOrderperson());
        System.out.println(shiporder.getOrderid());
      }))
      .subFlowMapping(PurchaseOrder.class, sf->sf.handle((MessageHandler) message -> {
        final PurchaseOrder purchaseOrderType = (PurchaseOrder) message.getPayload();
        System.out.println(purchaseOrderType.getBillTo().getName());
      }))
  ).get();
}

注意payloadRootMapping bean,讓我們解釋一下重要的部分:

  • <Object, Class<?>> route - 表示來自inboundChannel的輸入將是Object,並且將根據Class <?>執行路由
  • subFlowMapping(Shiporder.class.. - ShipOders的處理。
  • subFlowMapping(PurchaseOrder.class ... - 處理PurchaseOrders。

要測試ShipOrder有效負載,請使用示例3中的XML,以測試PurchaseOrder有效負載,使用以下XML:

<?xml version="1.0" encoding="utf-8"?> 
<PurchaseOrder OrderDate="1900-01-01" xmlns="http://tempuri.org/PurchaseOrderSchema.xsd"> 
 <ShipTo country="US"> 
  <name>name1</name> 
  <street>street1</street> 
  <city>city1</city> 
  <state>state1</state> 
  <zip>1</zip> 
 </ShipTo> 
 <ShipTo country="US"> 
  <name>name2</name> 
  <street>street2</street> 
  <city>city2</city> 
  <state>state2</state> 
  <zip>-79228162514264337593543950335</zip> 
 </ShipTo> 
 <BillTo country="US"> 
  <name>name1</name> 
  <street>street1</street> 
  <city>city1</city> 
  <state>state1</state> 
  <zip>1</zip> 
 </BillTo> 
</PurchaseOrder>

應根據subflow 子流Map路由兩個有效載荷。

示例5:IntegrationFlowAdapter

除了企業集成模式的其他實現(check them out)),我需要提到IntegrationFlowAdapter。通過擴展此類並實現buildFlow方法,如:

[url=https://bitbucket.org/Component/]@Component[/url] 
public class MyFlowAdapter extends IntegrationFlowAdapter {

@Autowired
 private ConnectionFactory rabbitConnectionFactory;

 @Override
 protected IntegrationFlowDefinition<?> buildFlow() {
   return from(Amqp.inboundAdapter(this.rabbitConnectionFactory, "myQueue"))
        .<String, String>transform(String::toLowerCase)
        .channel(c -> c.queue("myFlowAdapterOutput"));
 }

你可以將bean的重複聲明包裝成一個組件並給它們所需的流量。然後可以配置這樣的組件並將其作爲一個類實例提供給調用代碼!

因此,讓我們舉例說明這個repo中的示例3更短一些,併爲所有JmsEndpoints定義基類,並在其中定義重複bean:

public class JmsEndpoint extends IntegrationFlowAdapter {

  private String queueName;

  private String channelName;

  private String contextPath;

  /**
   * @param queueName
   * @param channelName
   * @param contextPath
   */
  public JmsEndpoint(String queueName, String channelName, String contextPath) {
    this.queueName = queueName;
    this.channelName = channelName;
    this.contextPath = contextPath;
  }

  @Override
  protected IntegrationFlowDefinition<?> buildFlow() {
    return from(Jms.messageDrivenChannelAdapter(listenerContainer())
      .jmsMessageConverter(new MarshallingMessageConverter(shipOrdersMarshaller()))
    ).channel(channelName);
  }

  @Bean
  public Jaxb2Marshaller shipOrdersMarshaller() {
    Jaxb2Marshaller marshaller = new Jaxb2Marshaller();
    marshaller.setContextPath(contextPath);
    return marshaller;
  }

  @Bean
  public DynamicDestinationResolver dynamicDestinationResolver() {
    return new DynamicDestinationResolver();
  }

  @Bean
  public ActiveMQConnectionFactory connectionFactory() {
    return new ActiveMQConnectionFactory();
  }

  @Bean
  public DefaultMessageListenerContainer listenerContainer() {
    final DefaultMessageListenerContainer defaultMessageListenerContainer = new DefaultMessageListenerContainer();
    defaultMessageListenerContainer.setDestinationResolver(dynamicDestinationResolver());
    defaultMessageListenerContainer.setConnectionFactory(connectionFactory());
    defaultMessageListenerContainer.setDestinationName(queueName);
    return defaultMessageListenerContainer;
  }

  @Bean
  public MessageChannel inboundChannel() {
    return MessageChannels.direct(channelName).get();
  }
}

現在聲明特定隊列的Jms端點很容易:

@Bean
public JmsEndpoint jmsEndpoint() {
  return new JmsEndpoint("jms.activeMQ.Test", "inboundChannel", "com.example.stubs");
}

inboundChannel的服務激活器:

/**
 * Sample 3, 5
 * @param shiporder
 */
@ServiceActivator(inputChannel = "inboundChannel")
public void processMessage(final Shiporder shiporder) {
  System.out.println(shiporder.getOrderid());
  System.out.println(shiporder.getOrderperson());
}

您不應該錯過在項目中使用IntegrationFlowAdapter。我喜歡它的概念。

我最近在Embedit的新的基於Spring Boot的項目中開始使用Spring Integration Java DSL 。即使有一些配置,我發現它非常有用。

  • 它很容易調試。不添加像wiretap這樣的配置。
  • 閱讀起來要容易得多。是的,即使是lambdas!
  • 它很強大。在Java配置中,您現在有很多選擇。

源碼地址:https://bitbucket.org/tomask79/spring-integration-java-dsl 

以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支持神馬文庫。

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