axis2实践（二）Restful入门示例

1. 实例说明

本示例直接参照了RESTful Web Services with Apache Axis2，本示例基本就是沿用的原示例，就是一个对学生信息（包括姓名，年龄，课程）的管理的例子，提供如下Web服务：

1）获取所有学生信息

2）根据姓名获取单个学生信息

3）新增学生信息

4）修改学生信息

另外，本示例在原示例的基础上增加如下功能：

1）增加了与Web系统的集成

2）增加客户端调用代码

2. 创建WebService服务，

整个项目目录结构见下图

1）创建StudentService类，提供了查询，获取，新增，修改学生信息的功能，特别需要注意的是，getStudent（）返回学生信息访问的URL.

 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Map;

 import org.apache.axis2.AxisFault;
 import org.apache.axis2.addressing.EndpointReference;
 import org.apache.axis2.context.MessageContext;
 import org.apache.axis2.description.TransportInDescription;
 import org.apache.axis2.engine.AxisConfiguration;

 public class StudentService {

     private Map<String, Student> map = new HashMap<String, Student>();
     private String baseURL = null;

     public StudentService() {
         map.put("jimmy", new Student("Jimmy", 20, new String[] { "English", "French", "Russian" }));
     }

     public String[] getStudents() {
         int size = map.size();
         String[] students = new String[size];
         Iterator<String> iterator = map.keySet().iterator();
         int i = 0;
         while (iterator.hasNext()) {
             String studentName = iterator.next();
             students[i] = getBaseURL() + "student/" + studentName;
             i++;
         }
         return students;
     }

     public Student getStudent(String name) throws StudentNotFoundException {
         Student student = map.get(name);
         if (student == null) {
             throw new StudentNotFoundException("Details of student " + name + " cannot be found.");
         }
         return student;
     }

     public String addStudent(Student student) throws StudentAlreadyExistsException {
         String name = student.getName();
         if (map.get(name) != null) {
             throw new StudentAlreadyExistsException("Cannot add details of student " + name
                     + ". Details of student " + name + " already exists.");
         }
         map.put(name, student);
         return getBaseURL() + "student/" + name;
     }

     public String updateStudent(Student student) throws StudentNotFoundException {
         String name = student.getName();
         if (map.get(name) == null) {
             throw new StudentNotFoundException("Details of student " + name + " cannot be found.");
         }
         map.put(name, student);
         return getBaseURL() + "student/" + name;
     }

     public void deleteStudent(String name) throws StudentNotFoundException {
         if (map.get(name) == null) {
             throw new StudentNotFoundException("Details of student " + name + " cannot be found.");
         }
         map.remove(name);
     }

     // This method attempts to get the Base URI for this service. This will be
     // used to construct
     // the URIs for the various detsila returned.
     private String getBaseURL() {
         if (baseURL == null) {
             MessageContext messageContext = MessageContext.getCurrentMessageContext();
             AxisConfiguration configuration = messageContext.getConfigurationContext()
                     .getAxisConfiguration();
             TransportInDescription inDescription = configuration.getTransportIn("http");
             try {
                 EndpointReference[] eprs = inDescription.getReceiver().getEPRsForService(
                         messageContext.getAxisService().getName(), null);
                 baseURL = eprs[0].getAddress();
             } catch (AxisFault axisFault) {
             }
         }
         return baseURL;
     }
 }

2)实体类:Student类

 public class Student {

     private String name;
     private int age;
     private String[] subjects;

     public Student() {
         super();
     }

     public Student(String name, int age, String[] subjects) {
         super();
         this.name = name;
         this.age = age;
         this.subjects = subjects;
     }

     public String getName() {
         return name;
     }

     public void setName(String name) {
         this.name = name;
     }

     public int getAge() {
         return age;
     }

     public void setAge(int age) {
         this.age = age;
     }

     public String[] getSubjects() {
         return subjects;
     }

     public void setSubjects(String[] subjects) {
         this.subjects = subjects;
     }
 }

3)异常类

StudentAlreadyExistsException类：

 public class StudentAlreadyExistsException extends Exception {
     private static final long serialVersionUID = 1L;

     public StudentAlreadyExistsException(String message) {
         super(message);
     }
 }

StudentNotFoundException类：

public class StudentNotFoundException extends Exception {
    private static final long serialVersionUID = 1L;

    public StudentNotFoundException(String message) {
        super(message);
    }
}

4）服务描述文件，创建此文件，并将此文件置于\WEB-INF\services\StudentService\META-INF目录下，如果不存在此目录，则创建

service.xml文件：

 <serviceGroup>
     <service name="StudentService" scope="application">
         <parameter name="ServiceClass">demo.axis2.restful.student.StudentService
         </parameter>
         <messageReceivers>
             <messageReceiver mep="http://www.w3.org/ns/wsdl/in-only"
                 class="org.apache.axis2.rpc.receivers.RPCInOnlyMessageReceiver" />
             <messageReceiver mep="http://www.w3.org/ns/wsdl/in-out"
                 class="org.apache.axis2.rpc.receivers.RPCMessageReceiver" />
         </messageReceivers>
     </service>
 </serviceGroup>

3. 利用java2wsdl工具生成WSDL2.0文档

生成命令如下：

java2wsdl -wv 2.0 -o <output directory> -of <output file name> -sn <Name of the service> -cp <classpath uri> -cn <fully qualified name of the service class>

本示例执行的命令如下：

java2wsdl -wv 2.0 -o D:\example\demo.axis2.restful\src\main\webapp\WEB-INF\services\StudentService\META-INF -of StudentService.wsdl -sn StudentService -cp D:\example\demo.axis2.restful\target\classes\ -cn demo.axis2.restful.student.StudentService

命令成功执行完之后，将在指定目录下生成StudentService.wsdl，本示例将StudentService.wsdl文件放在 D:\example\demo.axis2.restful\src\main\webapp\WEB-INF\services \StudentService\META-INF下，也是在maven打包整个项目时，便于将相应的文件构建到指定目录中。

4. 构建Restful服务

1）修改StudentService.wsdl文件如下部分

 <wsdl2:binding name="StudentServiceHttpBinding"
         interface="tns:ServiceInterface" whttp:methodDefault="POST"
         type="http://www.w3.org/ns/wsdl/http">
         <wsdl2:fault ref="tns:StudentServiceStudentNotFoundException" />
         <wsdl2:fault ref="tns:StudentServiceStudentAlreadyExistsException" />
         <wsdl2:operation ref="tns:deleteStudent"
             whttp:location="student/{name}" whttp:method="DELETE">
             <wsdl2:input />
             <wsdl2:output />
             <wsdl2:outfault ref="tns:StudentServiceStudentNotFoundException" />
         </wsdl2:operation>
         <wsdl2:operation ref="tns:updateStudent"
             whttp:location="student/{name}" whttp:method="PUT">
             <wsdl2:input />
             <wsdl2:output />
             <wsdl2:outfault ref="tns:StudentServiceStudentNotFoundException" />
         </wsdl2:operation>
         <wsdl2:operation ref="tns:getStudent" whttp:location="student/{name}"
             whttp:method="GET">
             <wsdl2:input />
             <wsdl2:output />
             <wsdl2:outfault ref="tns:StudentServiceStudentNotFoundException" />
         </wsdl2:operation>
         <wsdl2:operation ref="tns:addStudent" whttp:location="students"
             whttp:method="POST">
             <wsdl2:input />
             <wsdl2:output />
             <wsdl2:outfault ref="tns:StudentServiceStudentAlreadyExistsException" />
         </wsdl2:operation>
         <wsdl2:operation ref="tns:getStudents" whttp:location="students"
             whttp:method="GET">
             <wsdl2:input />
             <wsdl2:output />
         </wsdl2:operation>
     </wsdl2:binding>

2）修改web.xml，增加如下内容

<servlet>
    <servlet-name>AxisServlet</servlet-name>
    <display-name>Apache-Axis Servlet</display-name>
    <servlet-class>
        org.apache.axis2.transport.http.AxisServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>AxisServlet</servlet-name>
    <url-pattern>/services/*</url-pattern>
</servlet-mapping>

5. maven的项目管理文件pom.xml

 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <groupId>demo.axis2.restful</groupId>
     <artifactId>demo.axis2.restful</artifactId>
     <packaging>war</packaging>
     <version>1.0</version>
     <name>demo.axis2.restful Maven Webapp</name>
     <url>http://maven.apache.org</url>
     <dependencies>
         <dependency>
             <groupId>javax.servlet</groupId>
             <artifactId>servlet-api</artifactId>
             <version>2.4</version>
         </dependency>
         <dependency>
             <groupId>org.apache.axis2</groupId>
             <artifactId>axis2-kernel</artifactId>
             <version>1.6.2</version>
         </dependency>
         <dependency>
             <groupId>org.apache.axis2</groupId>
             <artifactId>axis2-jaxws</artifactId>
             <version>1.6.2</version>
         </dependency>
         <dependency>
             <groupId>org.apache.axis2</groupId>
             <artifactId>axis2-codegen</artifactId>
             <version>1.6.2</version>
         </dependency>
         <dependency>
             <groupId>org.apache.axis2</groupId>
             <artifactId>axis2-adb</artifactId>
             <version>1.6.2</version>
         </dependency>
         <dependency>
             <groupId>org.apache.axis2</groupId>
             <artifactId>axis2-transport-local</artifactId>
             <version>1.6.2</version>
         </dependency>
         <dependency>
             <groupId>org.apache.axis2</groupId>
             <artifactId>addressing</artifactId>
             <version>1.6.2</version>
             <type>mar</type>
         </dependency>
         <dependency>
             <groupId>com.sun.xml.ws</groupId>
             <artifactId>jaxws-rt</artifactId>
             <version>2.1.3</version>
             <exclusions>
                 <exclusion>
                     <groupId>javax.xml.ws</groupId>
                     <artifactId>jaxws-api</artifactId>
                 </exclusion>
                 <exclusion>
                     <groupId>com.sun.xml.bind</groupId>
                     <artifactId>jaxb-impl</artifactId>
                 </exclusion>
                 <exclusion>
                     <groupId>com.sun.xml.messaging.saaj</groupId>
                     <artifactId>saaj-impl</artifactId>
                 </exclusion>
                 <exclusion>
                     <groupId>com.sun.xml.stream.buffer</groupId>
                     <artifactId>streambuffer</artifactId>
                 </exclusion>
                 <exclusion>
                     <groupId>com.sun.xml.stream</groupId>
                     <artifactId>sjsxp</artifactId>
                 </exclusion>
                 <exclusion>
                     <groupId>org.jvnet.staxex</groupId>
                     <artifactId>stax-ex</artifactId>
                 </exclusion>
                 <exclusion>
                     <groupId>com.sun.org.apache.xml.internal</groupId>
                     <artifactId>resolver</artifactId>
                 </exclusion>
                 <exclusion>
                     <groupId>org.jvnet</groupId>
                     <artifactId>mimepull</artifactId>
                 </exclusion>
             </exclusions>
         </dependency>
         <dependency>
             <groupId>commons-logging</groupId>
             <artifactId>commons-logging</artifactId>
             <version>1.1.2</version>
         </dependency>
         <dependency>
             <groupId>log4j</groupId>
             <artifactId>log4j</artifactId>
             <version>1.2.17</version>
         </dependency>
         <dependency>
             <groupId>commons-logging</groupId>
             <artifactId>commons-logging</artifactId>
             <version>1.1.2</version>
         </dependency>
         <dependency>
             <groupId>commons-lang</groupId>
             <artifactId>commons-lang</artifactId>
             <version>2.6</version>
         </dependency>
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
             <version>3.8.1</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
     <build>
         <finalName>demo.axis2.restful</finalName>
         <plugins>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
                 <configuration>
                     <source>1.6</source>
                     <target>1.6</target>
                 </configuration>
             </plugin>
         </plugins>
         <resources>
             <resource>
                 <directory>src/main/resources</directory>
                 <includes>
                     <include>**/*</include>
                 </includes>
             </resource>
             <resource>
                 <directory>src/main/java</directory>
                 <includes>
                     <include>**/*.xml</include>
                 </includes>
             </resource>
         </resources>
     </build>
 </project>

6. 发布程序到tomcat或其他J2EE服务器，

启动服务器，就可在浏览器中通过如下URL http://localhost/demo.axis2.restful/services/StudentService?wsdl ,看到services定义了，说明服务发布成功

7. 客户端访问服务代码，

 import org.apache.axiom.om.OMAbstractFactory;
 import org.apache.axiom.om.OMElement;
 import org.apache.axiom.om.OMFactory;
 import org.apache.axiom.om.OMNamespace;
 import org.apache.axis2.AxisFault;
 import org.apache.axis2.Constants;
 import org.apache.axis2.addressing.EndpointReference;
 import org.apache.axis2.client.Options;
 import org.apache.axis2.client.ServiceClient;

 public class StudentClient {
     private static String toEpr = "http://localhost/demo.axis2.restful/services/StudentService";

     public static void main(String[] args) throws AxisFault {

         Options options = new Options();
         options.setTo(new EndpointReference(toEpr));

         options.setProperty(Constants.Configuration.ENABLE_REST, Constants.VALUE_TRUE);

         ServiceClient sender = new ServiceClient();
         //sender.engageModule(new QName(Constants.MODULE_ADDRESSING));
         sender.setOptions(options);
         OMElement result = sender.sendReceive(getPayload());
         System.out.println(result);

     }

     private static OMElement getPayload() {
         OMFactory fac = OMAbstractFactory.getOMFactory();
         OMNamespace omNs = fac.createOMNamespace("http://student.restful.axis2.demo", "tns");
         OMElement method = fac.createOMElement("addStudent", omNs);

         OMElement student = fac.createOMElement("addStudent", omNs);

         OMElement value = fac.createOMElement("name", omNs);
         value.addChild(fac.createOMText(value, "eric"));
         student.addChild(value);

         value = fac.createOMElement("age", omNs);
         value.addChild(fac.createOMText(value, "30"));
         student.addChild(value);

         value = fac.createOMElement("subjects", omNs);
         value.addChild(fac.createOMText(value, "English"));
         student.addChild(value);

         value = fac.createOMElement("subjects", omNs);
         value.addChild(fac.createOMText(value, "Russian"));
         student.addChild(value);

         method.addChild(student);
         return method;
     }
 }

另外还可以通过浏览直接访问，例如：http://localhost/demo.axis2.restful/services/StudentService/students 可以查询所有的学生信息，返回的信息如下：

 <ns:getStudentsResponse xmlns:ns="http://student.restful.axis2.demo">
 <ns:return>
     http://Localhost/demo.axis2.restful/services/StudentService/student/jimmy
 </ns:return>
 </ns:getStudentsResponse>

以上信息是在存在一个姓名为jimmy学生信息的情况下返回的。把 http://Localhost/demo.axis2.restful/services/StudentService/student /jimmy 复制到浏览器的地址栏，就可以查看学生的详细信息了。