Java WebService学习笔记

WebService 简介

实际开发中，很多系统都是基于历史遗留系统进行开发，有时，这些系统基于不同的语言，如C，C++，C#，java，PHP等等。为了实现历史系统的再利用，或向外部程序暴露调用接口，于是就产生了WebService规范。WebService用于实现系统的透明访问，其最终目的：实现异构系统间通信。

单从Java方面考虑，实现WebService的方法有jdk1.6版本添加的JWS，Axis1/2，XFIRE，Celtix，CXF（Xfire和Celtix的整合）。

综合来看Axis1，Xfire，Celtix成熟但即将退出的版本。内置的JWS，Axis和CXF却也不是很成熟（哎，青黄不接）。

Apache Axis1实现WebService

当利用Java版Axis有两个途径，以Java码作为Web服务。最简单的一种是使用原生的jws（Java Web Service的文件）。另一种方法是使用定制的部署文件。定制部署让您能自选资源，什么要予以曝光。

第一种实现方式：即时发布

实现此功能需要借助 axis-1_4webapps下的axis工程，将其部署到apache服务器webapps目录下。

原生的jws和java源代码的唯一区别是后缀名，当然采用这种方式也不能使用package进行打包.下面提供简单的原生jws和远程调用实现。

Hello.jws内容：

public class Hello
{
	public String sayHello(String name)
	{
		StringBuffer greeting = new StringBuffer("Hello ");
		if ( name != null )
		{
			greeting.append(name);
		}
		greeting.append(", nice to see you!");
		return greeting.toString();
	}
}

将Hello.jws文件放到apache服务器webapps/axis/目录下，启动服务器。

通过 http://localhost:8080/axis/Hello.jws?wsdl 可以获得Hello.jws的WebService定义，内容如下

<?xml version="1.0" encoding="UTF-8"?>
<wsdl:definitions targetNamespace="http://localhost:8080/axis/Hello.jws" 
 xmlns:apachesoap="http://xml.apache.org/xml-soap" 
 xmlns:impl="http://localhost:8080/axis/Hello.jws" 
 xmlns:intf="http://localhost:8080/axis/Hello.jws" 
 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="sayHelloResponse">

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

   </wsdl:message>

   <wsdl:message name="sayHelloRequest">

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

   </wsdl:message>

   <wsdl:portType name="Hello">

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

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

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

      </wsdl:operation>

   </wsdl:portType>

   <wsdl:binding name="HelloSoapBinding" type="impl:Hello">

      <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://DefaultNamespace" use="encoded"/>

         </wsdl:input>

         <wsdl:output name="sayHelloResponse">

            <wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" namespace="http://localhost:8080/axis/Hello.jws" use="encoded"/>

         </wsdl:output>

      </wsdl:operation>

   </wsdl:binding>

   <wsdl:service name="HelloService">

      <wsdl:port binding="impl:HelloSoapBinding" name="Hello">

         <wsdlsoap:address location="<span style="color:#FF0000;">http://localhost:8080/axis/Hello.jws</span>"/>

      </wsdl:port>

   </wsdl:service>

</wsdl:definitions>

至此，简单的Service端就部署成功了，接下来要通过一段程序对Hello.jws进行访问。

使用eclipse创建一个java project，并添加jar包，必须的jar包包括axis.jar;jaxrpc.jar;commons-loggin-1.x.jar;commons-discovery-0.x.jar

import javax.xml.namespace.QName;

import org.apache.axis.client.Call;
import org.apache.axis.client.Service;

public class HelloClient {

	public static void main(String[] args) {
		System.out.println(new HelloClient().sayHello("Han MeiMei"));
	}

	public String sayHello(String name)
	{
		String result = null;
		try
		{
			//1.设置远程访问链接
			String url = "http://localhost:8080/axis/Hello.jws";
			//2.获取Service对象
			Service service = new Service();
			//3.通过Service对象获取远程调用对象Call
			Call call = (Call) service.createCall();
			//4.设置远程调用桩
			call.setTargetEndpointAddress(url);
			//5.设置远程操作方法名
			call.setOperationName(new QName(url, "sayHello"));
			//6.设置参数，执行远程方法
			result = (String)call.invoke(new Object[]{name});
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		
		return result;
	}
}

执行结果如下：

May 19, 2014 2:11:40 PM org.apache.axis.utils.JavaUtils isAttachmentSupported
WARNING: Unable to find required classes (javax.activation.DataHandler and javax.mail.internet.MimeMultipart). Attachment support is disabled.
<span style="color:#FF0000;">Hello Han MeiMei, nice to see you!</span>

第二种实现方式：定制发布

第一种发布方式比较快捷，发布方式简单，但有以下缺点：

1.必须要有源文件，同时不能包含package结构

2.发布之后所有方法均开放，不可控制

针对以上缺点，axis提供定制发布方式，具体步骤如下：

编写Hello.java类

package com.webservice.wsdd;

public class Hello
{
    public String sayHello(String name)
    {
        StringBuffer greeting = new StringBuffer("Hello ");
        if(name != null)
        {
            greeting.append(name);
        }
        greeting.append(",nice to see you!");
        
        return greeting.toString();
    }
    
    public int add(int a,int b)
    {
        return a + b;
    }
}

使用命令行进行编译，得到class文件（包括包）

javac -d ./ Hello.java

将com包所有内容拷贝到apache服务器webapps/axis/WEB-INF/classes下。

编写hello.wsdd配置文件，放置到webapps/axis/WEB-INF/classes/com下   WSDD文档具体意义可查看Axis WSDD文件参考文档

<deployment name="test" xmlns="http://xml.apache.org/axis/wsdd/" 
    xmlns:java="http://xml.apache.org/axis/wsdd/providers/java">
  <!--Service name:服务名称，自己确定-->
  <service name="Hello" provider="java:RPC">
    <!--parameter 
        className：类路径及名称
        allowedMethods：可以指定方法名，也可以使用×代表全部
    -->
    <parameter name="className" value="com.webservice.wsdd.Hello" />
    <!-- 定制方法，此处指定制sayHello方法 -->
    <parameter name="allowedMethods" value="sayHello" />
  </service>

</deployment><span style="color:#FF0000;"><strong></strong></span>

启动服务器，进入到hello.wsdd位置，使用命令生成server-config.wsdd配置文件

java org.apache.axis.client.AdminClient hello.wsdd  --需要自己配置classpath环境变量

生成的server-config.wsdd配置文件位于webapps/axis/WEB-INF/路径下，内容如下，如果不想生成，也可以拷贝一份放在该路径下

<?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">
 <globalConfiguration>
  <parameter name="sendMultiRefs" value="true"/>
  <parameter name="disablePrettyXML" value="true"/>
  <parameter name="adminPassword" value="admin"/>
  <parameter name="attachments.Directory" value="E:apache-tomcat-7.0.53webappsaxisWEB-INFattachments"/>
  <parameter name="dotNetSoapEncFix" value="true"/>
  <parameter name="enableNamespacePrefixOptimization" value="false"/>
  <parameter name="sendXMLDeclaration" value="true"/>
  <parameter name="sendXsiTypes" value="true"/>
  <parameter name="attachments.implementation" value="org.apache.axis.attachments.AttachmentsImpl"/>
  <requestFlow>
   <handler type="java:org.apache.axis.handlers.JWSHandler">
    <parameter name="scope" value="session"/>
   </handler>
   <handler type="java:org.apache.axis.handlers.JWSHandler">
    <parameter name="scope" value="request"/>
    <parameter name="extension" value=".jwr"/>
   </handler>
  </requestFlow>
 </globalConfiguration>
 <handler name="URLMapper" type="java:org.apache.axis.handlers.http.URLMapper"/>
 <handler name="LocalResponder" type="java:org.apache.axis.transport.local.LocalResponder"/>
 <handler name="Authenticate" type="java:org.apache.axis.handlers.SimpleAuthenticationHandler"/>
 <service name="AdminService" provider="java:MSG">
  <parameter name="allowedMethods" value="AdminService"/>
  <parameter name="enableRemoteAdmin" value="false"/>
  <parameter name="className" value="org.apache.axis.utils.Admin"/>
  <namespace>http://xml.apache.org/axis/wsdd/</namespace>
 </service>
 <service name="Version" provider="java:RPC">
  <parameter name="allowedMethods" value="getVersion"/>
  <parameter name="className" value="org.apache.axis.Version"/>
 </service>
<span style="background-color: rgb(255, 255, 51);"> <service name="Hello" provider="java:RPC">
  <parameter name="allowedMethods" value="sayHello"/>
  <parameter name="className" value="com.webservice.wsdd.Hello"/>
 </service></span>
 <transport name="http">
  <requestFlow>
   <handler type="URLMapper"/>
   <handler type="java:org.apache.axis.handlers.http.HTTPAuthHandler"/>
  </requestFlow>
  <parameter name="qs:list" value="org.apache.axis.transport.http.QSListHandler"/>
  <parameter name="qs:wsdl" value="org.apache.axis.transport.http.QSWSDLHandler"/>
  <parameter name="qs.list" value="org.apache.axis.transport.http.QSListHandler"/>
  <parameter name="qs.method" value="org.apache.axis.transport.http.QSMethodHandler"/>
  <parameter name="qs:method" value="org.apache.axis.transport.http.QSMethodHandler"/>
  <parameter name="qs.wsdl" value="org.apache.axis.transport.http.QSWSDLHandler"/>
 </transport>
 <transport name="local">
  <responseFlow>
   <handler type="LocalResponder"/>
  </responseFlow>
 </transport>
</deployment>

使用http://localhost:8080/axis/services/Hello?wsdl 可以查看WebService描述，内容如下

<?xml version="1.0" encoding="UTF-8"?>
<wsdl:definitions targetNamespace="http://localhost:8080/axis/services/Hello" xmlns:apachesoap="http://xml.apache.org/xml-soap" xmlns:impl="http://localhost:8080/axis/services/Hello" xmlns:intf="http://localhost:8080/axis/services/Hello" 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="sayHelloResponse">

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

   </wsdl:message>

   <wsdl:message name="sayHelloRequest">

      <wsdl:part name="in0" type="soapenc:string"/>

   </wsdl:message>

   <wsdl:portType name="Hello">

      <wsdl:operation name="sayHello" parameterOrder="in0">

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

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

      </wsdl:operation>

   </wsdl:portType>

   <wsdl:binding name="HelloSoapBinding" type="impl:Hello">

      <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://wsdd.webservice.com" use="encoded"/>

         </wsdl:input>

         <wsdl:output name="sayHelloResponse">

            <wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" namespace="http://localhost:8080/axis/services/Hello" use="encoded"/>

         </wsdl:output>

      </wsdl:operation>

   </wsdl:binding>

   <wsdl:service name="HelloService">

      <wsdl:port binding="impl:HelloSoapBinding" name="Hello">

         <wsdlsoap:address location="<span style="color:#FF0000;">http://localhost:8080/axis/services/Hello</span>"/>

      </wsdl:port>

   </wsdl:service>

</wsdl:definitions>

此时定制服务发布完成。

访问方式只需把第一步的访问链接替换成上面红字部分即可

补充：开发中，有时候需要通过WebService传递对象，此时的处理方式与上述方法又有不同

Axis处理对象参数/返回值

编写Question.java和Answer.java   注意：Bean对象一定要实现Serializable接口。

package com.webservice.wsdd;

import java.io.Serializable;

@SuppressWarnings("serial")
public class Question implements Serializable
{
	private int id;
	
	private String question;
	
	private String answer;
	
	public void setId(int id)
	{
		this.id = id;
	}
	
	public int getId()
	{
		return this.id;
	}
	
	public void setQuestion(String question)
	{
		this.question = question;
	}
	
	public String getQuestion()
	{
		return this.question;
	}
	
	public void setAnswer(String answer)
	{
		this.answer = answer;
	}
	
	public String getAnswer()
	{
		return this.answer;
	}
}

package com.webservice.wsdd;

public class Answer
{
	public Question answerQuestion(Question question)
	{
		Question tmp = question;
		
		doRead(tmp);
		tmp.setAnswer("do not know the answer!");
		
		return tmp;
	}
	
	private void doRead(Question question)
	{
		System.out.println("read question:"+question.getQuestion());
	}
}

编译后放到服务器classes目录下，在server-config.wsdd中注册服务,较之前多了红字部分。

        <service name="Answer" provider="java:RPC">
		<parameter name="className" value="com.webservice.wsdd.Answer"/>
		<parameter name="allowedMethods" value="*"/>
		<span style="color:#FF0000;"><!-- 
			qname：自定义bean名称
			xmlns：自定义的xml命名空间，xmlns冒号后面部分取自qname属性，必须要有，否则报错
			languageSpecificType：语言类型及类路径
		-->
		<beanMapping
			qname="bean:Question"
			xmlns:bean="BeanManger"
			languageSpecificType="java:com.webservice.wsdd.Question"
		/></span>
	</service>

启动服务器，服务发布成功。可以在 http://localhost:8080/axis/servlet/AxisServlet 下查看到该服务

客户端代码QuestionClient.java

package com.client;

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

import org.apache.axis.client.Call;
import org.apache.axis.client.Service;
import org.apache.axis.encoding.ser.BeanDeserializerFactory;
import org.apache.axis.encoding.ser.BeanSerializerFactory;

import com.webservice.wsdd.Question;

public class QuestionClient {

	public static void main(String[] args) {
		Question question = new Question();
		question.setQuestion("先有鸡还是先有蛋！");
		
		new QuestionClient().askAndAnswer(question);
	}

	/**
	 * @param question
	 */
	public void askAndAnswer(Question question)
	{
		String url = "http://localhost:8080/axis/services/Answer";
		Service service = new Service();
		
		try
		{
			Call call = (Call)service.createCall();
			
			call.setTargetEndpointAddress(url);
			
			//注册Bean及序列化和反序列化工程映射关系
			QName qname = new QName("bean:BeanManger","Question");
			call.registerTypeMapping(Question.class, qname, 
					new BeanSerializerFactory(Question.class, qname),
					new BeanDeserializerFactory(Question.class, qname)
			);
			call.setOperationName(new QName(url, "answerQuestion"));
			call.setReturnClass(Question.class);
			
			//设置调用方法的参数
			call.addParameter("question", qname, ParameterMode.IN);
			
			Question tmp = (Question)call.invoke(new Object[]{question});
			
			if(tmp!=null)
			{
				System.out.println("Question:"+tmp.getQuestion());
				System.out.println("Answer:"+tmp.getAnswer());
			}
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
}

执行结果：

Question:先有鸡还是先有蛋！
Answer:do not know the answer!

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