利用Java编写简单的WebService实例

 

     使用Axis编写WebService比较简单，就我的理解，WebService的实现代码和编写Java代码其实没有什么区别，主要是将哪些Java类发布为WebService。下面是一个从编写测试例子到发布WebService，以及编写测试代码的过程介绍。

      本例子的WebService提供了两个方法，分别是sayHello和sayHelloToPerson，第一个只是返回一个"Hello"字符串，没有参数，第二个函数接受一个字符串作为参数，返回"Hello 参数值"，该例子比较简单，但是清楚的说明了从编写代码到发布为WebService以及测试编写好的WebService全过程。

编写服务代码

      服务代码提供了两个函数，分别为sayHello和sayHelloToPerson，源代码如下：

/*
 * File name: HelloService.java
 *
 * Version: v1.0
 *
 * Created on Aug 2, 2008 9:40:20 AM
 *
 * Designed by Stephen
 *
 * (c)Copyright 2008
 */
package com.sinosoft.webservice;

/** *//**
 * @author Stephen
 *
 * Test web service
 */
public class HelloService {
    /** *//**
     * 不带参数的函数
     *
     * @return 返回Hello字符串
     */
    public String sayHello() {
        return "Hello";
    }

    /** *//**
     * 带参数的函数
     *
     * @param name
     *            名称
     * @return 返回加上名称的欢迎词
     */
    public String sayHelloToPerson(String name) {
        if (name == null || name.equals("")) {
            name = "nobody";
        }
        return "Hello " + name;
    }
}

 

 

发布WebService

      要将上边写的HelloService类发布为WebService，需要先搭建Web应用。下面是在Tomcat下使用Axis（http://ws.apache.org/axis/）创建WebService服务的例子。

在Tomcat下创建Web应用

在该例子中，在Tomcat下创建了一个context path为ws的WEB应用。

     1. 在myeclipse中创建WebServiceTest的webproject

     2. 在WEB-INF文件夹下web.xml文件，该文件的内容如下：

<?xml version="1.0" encoding="ISO-8859-1"?>

<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web
Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd">

<web-app>
  <display-name>Apache-Axis</display-name>

    <listener>
        <listener-class>org.apache.axis.transport.http.AxisHTTPSessionListener</listener-class>
    </listener>

  <servlet>
    <servlet-name>AxisServlet</servlet-name>
    <display-name>Apache-Axis Servlet</display-name>
    <servlet-class>
        org.apache.axis.transport.http.AxisServlet
    </servlet-class>
  </servlet>

  <servlet>
    <servlet-name>AdminServlet</servlet-name>
    <display-name>Axis Admin Servlet</display-name>
    <servlet-class>
        org.apache.axis.transport.http.AdminServlet
    </servlet-class>
    <load-on-startup>100</load-on-startup>
  </servlet>

  <servlet>
    <servlet-name>SOAPMonitorService</servlet-name>
    <display-name>SOAPMonitorService</display-name>
    <servlet-class>
        org.apache.axis.monitor.SOAPMonitorService
    </servlet-class>
    <init-param>
      <param-name>SOAPMonitorPort</param-name>
      <param-value>5001</param-value>
    </init-param>
    <load-on-startup>100</load-on-startup>
  </servlet>

  <servlet-mapping>
    <servlet-name>AxisServlet</servlet-name>
    <url-pattern>/servlet/AxisServlet</url-pattern>
  </servlet-mapping>

  <servlet-mapping>
    <servlet-name>AxisServlet</servlet-name>
    <url-pattern>*.jws</url-pattern>
  </servlet-mapping>

  <servlet-mapping>
    <servlet-name>AxisServlet</servlet-name>
    <url-pattern>/services/*</url-pattern>
  </servlet-mapping>

  <servlet-mapping>
    <servlet-name>SOAPMonitorService</servlet-name>
    <url-pattern>/SOAPMonitor</url-pattern>
  </servlet-mapping>

 <!-- uncomment this if you want the admin servlet -->
 <!--
  <servlet-mapping>
    <servlet-name>AdminServlet</servlet-name>
    <url-pattern>/servlet/AdminServlet</url-pattern>
  </servlet-mapping>
 -->

    <session-config>
        <!-- Default to 5 minute session timeouts -->
        <session-timeout>5</session-timeout>
    </session-config>

    <!-- currently the W3C havent settled on a media type for WSDL;
    http://www.w3.org/TR/2003/WD-wsdl12-20030303/#ietf-draft
    for now we go with the basic 'it's XML' response -->
  <mime-mapping>
    <extension>wsdl</extension>
     <mime-type>text/xml</mime-type>
  </mime-mapping>


  <mime-mapping>
    <extension>xsd</extension>
    <mime-type>text/xml</mime-type>
  </mime-mapping>

  <welcome-file-list id="WelcomeFileList">
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.jws</welcome-file>
  </welcome-file-list>

</web-app>

 

 

在上面的web.xml中主要是配置了axis的相关配置。

axis的相关配置

在上述的web.xml文件中已经对axis进行了配置，但是还需要进行额外的配置。

     复制axis相关的jar文件

     将axis的相关jar文件复制到WEB-INF\lib文件夹下。这些文件包括：

activation.jar
axis.jar
axis-ant.jar
commons-discovery-0.2.jar
commons-logging-1.0.4.jar
jaxrpc.jar
log4j-1.2.8.jar
saaj.jar
wsdl4j-1.5.1.jar

 

测试发布的Web应用

启动Tomcat服务，打开IE浏览器，访问地址http://127.0.0.1:8080/WebServiceTest/services，如果看到如下界面就说明AXIS部署成功了。

 

 

发布WebService

     发布WebService需要使用现有的AdminService来实现，这里我写了一个批处理文件来发布WebService，以后如果需要发布其他文件，只需要修改相应的参数就可以了。

创建deploy.wsdd文件

文件deploy.wsdd内容如下所示：

<?xml version="1.0" encoding="UTF-8"?>
<deployment xmlns="http://xml.apache.org/axis/wsdd/" xmlns:java="http://xml.apache.org/axis/wsdd/providers/java">
    <service name="HelloServices" provider="java:RPC">
        <parameter name="className" value="com.sinosoft.webservice.HelloService"/>
        <parameter name="allowedMethods" value="*"/>
    </service>
</deployment>

 

 

创建发布WebService服务的批处理文件

批处理文件deploywebservice.bat内容如下：

java -cp axis-ant.jar;axis-schema.jar;axis.jar;commons-discovery-0.2.jar;commons-logging-1.0.4.jar;jaxrpc.jar;log4j-1.2.8.jar;saaj.jar;wsdl4j-1.5.1.jar;xmlsec-1.3.0.jar org.apache.axis.client.AdminClient -lhttp://localhost:8080/WebServiceTest/services/AdminService deploy.wsdd

pause

 

 

  其中上面的jar包我都拷到和bat文件在同一个目录，现在将所有的jar文件都加入到classpath中进行执行。

     -l后的参数是本地要发布WebService的AdminService对应的访问地址。

     最后deploy.wsdd是对应的配置文件名称。

发布WebService服务

将deploy.wsdd文件和deploywebservice.bat文件复制到同一个文件夹下，执行deploywebservice.bat批处理文件，就可以将deploy.wsdd中描述的Java类发布为WebService。发布完成之后在访问http://host:port/ws/services如下图所示：

 

 

 

 

从上图可以看出，发布成功后，多了一个HelloServices的服务。这样就说明HelloService发布成功了。

查看HelloServices的wsdl

     访问http://127.0.0.1:8080/WebServiceTest/services/HelloServices?wsdl可以看到如下wsdl的内容：

<?xml version="1.0" encoding="UTF-8"?>
<wsdl:definitions targetNamespace="http://127.0.0.1:8080/WebServiceTest/services/HelloServices" xmlns:apachesoap="http://xml.apache.org/xml-soap" xmlns:impl="http://127.0.0.1:8080/WebServiceTest/services/HelloServices" xmlns:intf="http://127.0.0.1:8080/WebServiceTest/services/HelloServices" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns:wsdlsoap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<!--WSDL created by Apache Axis version: 1.4
Built on Apr 22, 2006 (06:55:48 PDT)-->

   <wsdl:message name="sayHelloToPersonRequest">

      <wsdl:part name="name" type="soapenc:string"/>

   </wsdl:message>

   <wsdl:message name="sayHelloRequest">

   </wsdl:message>

   <wsdl:message name="sayHelloToPersonResponse">

      <wsdl:part name="sayHelloToPersonReturn" type="soapenc:string"/>

   </wsdl:message>

   <wsdl:message name="sayHelloResponse">

      <wsdl:part name="sayHelloReturn" type="soapenc:string"/>

   </wsdl:message>

   <wsdl:portType name="HelloService">

      <wsdl:operation name="sayHello">

         <wsdl:input message="impl:sayHelloRequest" name="sayHelloRequest"/>

         <wsdl:output message="impl:sayHelloResponse" name="sayHelloResponse"/>

      </wsdl:operation>

      <wsdl:operation name="sayHelloToPerson" parameterOrder="name">

         <wsdl:input message="impl:sayHelloToPersonRequest" name="sayHelloToPersonRequest"/>

         <wsdl:output message="impl:sayHelloToPersonResponse" name="sayHelloToPersonResponse"/>

      </wsdl:operation>

   </wsdl:portType>

   <wsdl:binding name="HelloServicesSoapBinding" type="impl:HelloService">

      <wsdlsoap:binding style="rpc" transport="http://schemas.xmlsoap.org/soap/http"/>

      <wsdl:operation name="sayHello">

         <wsdlsoap:operation soapAction=""/>

         <wsdl:input name="sayHelloRequest">

            <wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" namespace="http://webservice.sinosoft.com" use="encoded"/>

         </wsdl:input>

         <wsdl:output name="sayHelloResponse">

            <wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" namespace="http://127.0.0.1:8080/WebServiceTest/services/HelloServices" use="encoded"/>

         </wsdl:output>

      </wsdl:operation>

      <wsdl:operation name="sayHelloToPerson">

         <wsdlsoap:operation soapAction=""/>

         <wsdl:input name="sayHelloToPersonRequest">

            <wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" namespace="http://webservice.sinosoft.com" use="encoded"/>

         </wsdl:input>

         <wsdl:output name="sayHelloToPersonResponse">

            <wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" namespace="http://127.0.0.1:8080/WebServiceTest/services/HelloServices" use="encoded"/>

         </wsdl:output>

      </wsdl:operation>

   </wsdl:binding>

   <wsdl:service name="HelloServiceService">

      <wsdl:port binding="impl:HelloServicesSoapBinding" name="HelloServices">

         <wsdlsoap:address location="http://127.0.0.1:8080/WebServiceTest/services/HelloServices"/>

      </wsdl:port>

   </wsdl:service>

</wsdl:definitions>

 

用Java调用WebService实例

     下面是用Java调用刚发布的WebService例子。

 

/*
 * File name: TestHelloService.java
 *
 * Version: v1.0
 *
 * Created on Aug 2, 2008 9:54:10 AM
 *
 * Designed by Stephen
 *
 * (c)Copyright 2008
 */
package test.com.sinosoft.webservice;

import java.io.IOException;
import java.net.MalformedURLException;

import javax.xml.namespace.QName;
import javax.xml.rpc.ServiceException;

import org.apache.axis.client.Call;
import org.apache.axis.client.Service;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * @author Stephen
 *
 * 测试调用WebService
 */
public class TestHelloService {
    private static final Log log = LogFactory.getLog(TestHelloService.class);
    private static final String HELLO_SERVICE_ENDPOINT = "http://127.0.0.1:8080/WebServiceTest/services/HelloServices?wsdl";

    public static void main(String[] args) {
        TestHelloService tester = new TestHelloService();
        // tester.callSayHello();
        tester.callSayHelloToPerson();
    }

    public void callSayHello() {
        try {
            Service service = new Service();
            Call call = (Call) service.createCall();
            call.setTargetEndpointAddress(new java.net.URL(
                    HELLO_SERVICE_ENDPOINT));
            //下面名字查询的http://127.0.0.1:8080/WebServiceTest/services/HelloServices?wsdl文件里有
            call.setOperationName(new QName("http://webservice.sinosoft.com/",
                    "sayHello"));
            call.setReturnType(org.apache.axis.Constants.XSD_STRING);
            try {
                //远程调用发布的方法
                String ret = (String) call.invoke(new Object[] {});
                System.out.println("The return value is:" + ret);
                return;
            } catch (IOException e) {
                e.printStackTrace();
            }
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (ServiceException e) {
            e.printStackTrace();
        }
        log.error("call sayHello service error!");
    }

    public void callSayHelloToPerson() {
        try {
            Service service = new Service();
            Call call = (Call) service.createCall();
            call.setTargetEndpointAddress(new java.net.URL(HELLO_SERVICE_ENDPOINT));
            call.setOperationName(new QName("http://webservice.sinosoft.com/",
                    "sayHelloToPerson"));
            call.addParameter("name", org.apache.axis.Constants.XSD_STRING,
                    javax.xml.rpc.ParameterMode.IN);
            call.setReturnType(org.apache.axis.Constants.XSD_STRING);
            try {
                String ret = (String) call.invoke(new Object[] { "Stephen" });
                System.out.println("The return value is:" + ret);
                return;
            } catch (IOException e) {
                e.printStackTrace();
            }
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (ServiceException e) {
            e.printStackTrace();
        }
        log.error("call sayHello service error!");
    }
}

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