Jersey构建Restful风格的Webserivces（三）

一、总体说明

通过jersey-client接口，创建客户端程序，来调用Jersey实现的RESTful服务，实现增、删、改、查等操作。

服务端主要是通过内存的方式，来模拟用户的增加、删除、修改、查询等操作。

二、创建服务端

1.在上文项目中，

在“com.waylau.rest.resources.UserResource“中修改代码，

首先创建一个HashMap，用来保存添加的用户

[java] view plaincopyprint?

1. private static Map<String,User> userMap  = new HashMap<String,User>();

private static Map<String,User> userMap  = new HashMap<String,User>();

2.创建增、删、改、查 用户资源等操作

/**
     * 增加
     * @param user
     */
    @POST
    @Consumes({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
    public void createStudent(User user)
    {
        userMap.put(user.getUserId(), user );
    }

    /**
     * 删除
     * @param id
     */
    @DELETE
    @Path("{id}")
    public void deleteStudent(@PathParam("id")String id){
        userMap.remove(id);
    }

    /**
     * 修改
     * @param user
     */
    @PUT
    @Consumes(MediaType.APPLICATION_XML)
    public void updateStudent(User user){
        userMap.put(user.getUserId(), user );
    }

    /**
     * 根据id查询
     * @param id
     * @return
     */
    @GET
    @Path("{id}")
    @Produces({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
    public User getUserById(@PathParam("id") String id){
        User u = userMap.get(id);
        return u;
    }

    /**
     * 查询所有
     * @return
     */
    @GET
    @Produces({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
    public List<User> getAllUsers(){
        List<User> users = new ArrayList<User>();
        users.addAll( userMap.values() );
        return users;
    }
    

三、创建客户端程序

1.创建包“com.waylau.rest.client”，在包下建一个UserClient.java，代码如下：

package com.waylau.rest.client;

import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Entity;
import javax.ws.rs.client.WebTarget;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

import org.codehaus.jackson.jaxrs.JacksonJsonProvider;

import com.waylau.rest.bean.User;

/**
 * 用户客户端，用来测试资源
 * @author waylau.com
 * 2014-3-18
 */
public class UserClient {

    private static String serverUri = "http://localhost:8089/RestDemo/rest";
    /**
     * @param args
     */
    public static void main(String[] args) {
        addUser();
        getAllUsers();
        updateUser();
        getUserById();
        getAllUsers();
        delUser();
        getAllUsers();

    }
    /**
     * 添加用户
     */
     private static void addUser() {
         System.out.println("****增加用户addUser****");
         User user = new User("006","Susan","21");
         Client client = ClientBuilder.newClient();
         WebTarget target = client.target(serverUri + "/users");
         Response response = target.request().buildPost(Entity.entity(user, MediaType.APPLICATION_XML)).invoke();
         response.close();
    }

    /**
     * 删除用户
     */
     private static void delUser() {
         System.out.println("****删除用户****");
         Client client = ClientBuilder.newClient();
         WebTarget target = client.target(serverUri + "/users/006");
         Response response = target.request().delete();
         response.close();
    }

    /**
     * 修改用户
     */
     private static void updateUser() {
         System.out.println("****修改用户updateUser****");
         User user = new User("006","Susan","33");
         Client client = ClientBuilder.newClient();
         WebTarget target = client.target(serverUri + "/users");
         Response response = target.request().buildPut( Entity.entity(user, MediaType.APPLICATION_XML)).invoke();
         response.close();
    }
    /**
     * 根据id查询用户
     */
     private static void getUserById() {
         System.out.println("****根据id查询用户****");
         Client client = ClientBuilder.newClient().register(JacksonJsonProvider.class);// 注册json 支持
         WebTarget target = client.target(serverUri + "/users/006");
         Response response = target.request().get();
         User user = response.readEntity(User.class);
         System.out.println(user.getUserId() + user.getUserName()  +  user.getAge());
         response.close();
    }
    /**
     * 查询所有用户
     */
     private static void getAllUsers() {
         System.out.println("****查询所有getAllUsers****");

         Client client = ClientBuilder.newClient();

         WebTarget target = client.target(serverUri + "/users");
         Response response = target.request().get();
          String value = response.readEntity(String.class);
              System.out.println(value);
             response.close();  //关闭连接
     }

}

四、运行

启动服务端项目，运行客户端程序UserClient，控制台输出如下

[html] view plaincopyprint?

1. ****增加用户addUser****
2. ****查询所有getAllUsers****
3. [{"userId":"006","userName":"Susan","age":"21"}]
4. ****修改用户updateUser****
5. ****根据id查询用户****
6. 006Susan33
7. ****查询所有getAllUsers****
8. [{"userId":"006","userName":"Susan","age":"33"}]
9. ****删除用户****
10. ****查询所有getAllUsers****
11. []

****增加用户addUser****
****查询所有getAllUsers****
[{"userId":"006","userName":"Susan","age":"21"}]
****修改用户updateUser****
****根据id查询用户****
006Susan33
****查询所有getAllUsers****
[{"userId":"006","userName":"Susan","age":"33"}]
****删除用户****
****查询所有getAllUsers****
[]

五、总结

1.客户端如果需要进行JSON转换，需要进行JSON注册

[java] view plaincopyprint?

1. Client client = ClientBuilder.newClient().register(JacksonJsonProvider.class);

 Client client = ClientBuilder.newClient().register(JacksonJsonProvider.class);

2.WebTarget 指明了要请求的资源的地址

3.target.request(). 后面跟的是请求的方法:POST，GET，PUT或DELETE

转自：http://blog.csdn.net/kkkloveyou/article/details/21517165