Spring Boot集成Java DSL的實(shí)現(xiàn)代碼

更新時(shí)間：2019年01月08日 15:05:05 作者：banq

這篇文章主要介紹了Spring Boot集成Java DSL的實(shí)現(xiàn)代碼，文中通過(guò)示例代碼介紹的非常詳細(xì)，對(duì)大家的學(xué)習(xí)或者工作具有一定的參考學(xué)習(xí)價(jià)值，需要的朋友們下面隨著小編來(lái)一起學(xué)習(xí)學(xué)習(xí)吧

Spring Integration Java DSL已經(jīng)融合到Spring Integration Core 5.0，這是一個(gè)聰明而明顯的舉動(dòng)，因?yàn)椋?/p>

基于Java Config啟動(dòng)新Spring項(xiàng)目的每個(gè)人都使用它
SI Java DSL使您可以使用Lambdas等新的強(qiáng)大Java 8功能
您可以使用基于IntegrationFlowBuilder的Builder模式構(gòu)建流

讓我們看看基于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(wǎng)關(guān)

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(duì)列發(fā)送到Gateway風(fēng)格的激活器，那么請(qǐng)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(guò)dataEndpoint bean 返回JmsInboundGatewaySpec，您還可以向SI通道或Jms目標(biāo)發(fā)送回復(fù)。查看文檔。

示例2：Jms消息驅(qū)動(dòng)的通道適配器

如果您正在尋找替換消息驅(qū)動(dòng)通道適配器的XML JMS配置，那么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(fù)載如樣本1中一樣發(fā)送給激活器。

示例3：使用JAXB的Jms消息驅(qū)動(dòng)的通道適配器

在典型的場(chǎng)景中，您希望通過(guò)Jms接受XML作為文本消息，將其轉(zhuǎn)換為JAXB存根并在服務(wù)激活器中處理它。我將向您展示如何使用SI Java DSL執(zhí)行此操作，但首先讓我們?yōu)閤ml處理添加兩個(gè)依賴項(xiàng)：

<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(guò)JMS接受shiporders ，所以首先XSD命名為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(jīng)準(zhǔn)備好了存根類和一切，現(xiàn)在使用Jaxb magic的Java DSL JMS消息驅(qū)動(dòng)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中使用它可以為您提供如此強(qiáng)大的功能和靈活性。要完成此示例，inboundChannel的服務(wù)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(cè)試流，您可以使用以下XML通過(guò)JConsole發(fā)送到JMS隊(duì)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(fù)載根路由的Jms消息驅(qū)動(dòng)的通道適配器

另一種典型情況是接受XML作為JMS文本消息，將其轉(zhuǎn)換為JAXB存根并根據(jù)有效負(fù)載根類型將有效負(fù)載路由到某個(gè)服務(wù)激活器。當(dāng)然SI Java DSL支持所有類型的路由，我將向您展示如何根據(jù)有效載荷類型進(jìn)行路由。

首先，將以下XSD添加到shiporder.xsd所在的文件夾中，并將其命名為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>

然后添加到j(luò)axb 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(yùn)行mvn clean install以生成新XSD的JAXB存根?，F(xiàn)在承諾有效負(fù)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(lái)自inboundChannel的輸入將是Object，并且將根據(jù)Class <？>執(zhí)行路由
subFlowMapping(Shiporder.class.. - ShipOders的處理。
subFlowMapping(PurchaseOrder.class ... - 處理PurchaseOrders。

要測(cè)試ShipOrder有效負(fù)載，請(qǐng)使用示例3中的XML，以測(cè)試PurchaseOrder有效負(fù)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(yīng)根據(jù)subflow 子流Map路由兩個(gè)有效載荷。

示例5：IntegrationFlowAdapter

除了企業(yè)集成模式的其他實(shí)現(xiàn)（check them out)），我需要提到IntegrationFlowAdapter。通過(guò)擴(kuò)展此類并實(shí)現(xiàn)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的重復(fù)聲明包裝成一個(gè)組件并給它們所需的流量。然后可以配置這樣的組件并將其作為一個(gè)類實(shí)例提供給調(diào)用代碼！

因此，讓我們舉例說(shuō)明這個(gè)repo中的示例3更短一些，并為所有JmsEndpoints定義基類，并在其中定義重復(fù)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(xiàn)在聲明特定隊(duì)列的Jms端點(diǎn)很容易：

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

inboundChannel的服務(wù)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(yīng)該錯(cuò)過(guò)在項(xiàng)目中使用IntegrationFlowAdapter。我喜歡它的概念。

我最近在Embedit的新的基于Spring Boot的項(xiàng)目中開始使用Spring Integration Java DSL 。即使有一些配置，我發(fā)現(xiàn)它非常有用。