RESTful/SpringMVC实现

注解：

• @RestController：Spring 4的新注解。 她自动为每个方法加上 @ResponseBody. @RestController可以看做是 @Controller 和@ResponseBody两个注解的组合。
• @RequestBody： 如果一个方法申明了@RequestBody注解, Spring会基于请求头中的Content-Type使用HTTP Message converters将request body反序列化成对象。
• @ResponseBody：是在方法的上注解，如果一个方法申明了@ResponseBody, Spring会基于请求头中的Accept使用HTTP Message converters将对象序列化成response body。在Spring 4中如果使用了@RestController，则可以不用再声明此注解。

返回类型：

• ResponseEntity：ResponseEntity很重要。 她代表了整个HTTP response. 你可以指定status code, response headers, response body.。她有几种构造方法可以在HTTP Response中传递信息。
• MediaType：随@RequestMapping一起使用, 你可以指定生产和消费的类型(使用@Produces或@Consumes属性) 。
  例如：
  @RequestMapping(value = "/say/{msg}", produces="application/json;charset=UTF-8")
  仅当request请求头中的(Accept)类型中包含该指定类型才返回。
  @RequestMapping(produces={"text/html", "application/json"})
  将匹配Accept:text/html或Accept:application/json。
  当你有如下Accept头“Accept：text/html,application/xml,application/json”，将按照顺序进行produces的匹配

作为服务端，@Produces 标注用于指定返回的MIME媒体类型，@Consumes 标注服务端只可接受此MIME媒体类型的请求。。
作为客户端，Content-Type 请求头用于指定返回的MIME媒体类型。**Accept **请求头用于标注客户端只可接受此MIME媒体类型的请求。

//请求的地址  
String url = "http://localhost:9080/springmvc-chapter6/request/ContentType";  
//①创建Http Request(内部使用HttpURLConnection)  
ClientHttpRequest request = new SimpleClientHttpRequestFactory().createRequest(new URI(url), HttpMethod.POST);  
//②设置请求头的内容类型头和内容编码（GBK）  
request.getHeaders().set("Content-Type", "application/json;charset=gbk");  
//③以GBK编码写出请求内容体  
String jsonData = "{\"username\":\"zhang\", \"password\":\"123\"}";  
request.getBody().write(jsonData.getBytes("gbk"));  
//④发送请求并得到响应  
ClientHttpResponse response = request.execute();  
System.out.println(response.getStatusCode());  

添加jackson相关包
如果导入jackson-databind.jar，则@ResponseBody注解的方法或@RestController注解的Controller默认返回JSON格式。另外再倒入jackson-dataformat-xml.jar的话默认返回XML，此时如需返回JSON可在请求最后加上".json"。
注：org.codehaus.jackson是旧版本的com.fasterxml.jackson。如果项目中需要jackson-databind，则只需要引入它。jackson-core和jackson-annotations会随它自动引入。

    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>${jackson.library}</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.dataformat</groupId>
        <artifactId>jackson-dataformat-xml</artifactId>
        <version>${jackson.library}</version>
    </dependency>

使用@RestController：
服务端：

package com.zzhblh.resource.impl;

import com.zzhblh.entity.account.User;
import com.zzhblh.resource.UserResource;
import org.springframework.http.MediaType;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.*;

import java.util.Map;


/**
 * Created by chen on 2016/9/2.
 */
@RestController
@RequestMapping("api/user_resource")
public class UserResourceImpl implements UserResource{

    @Override
    @RequestMapping(value = "/user_query", method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
    public User queryUserInfoById(@RequestParam(value="id") String id) {
        return new User("123","abc");
    }

    @Override
    @RequestMapping(value = "/user_update/{id}", method = RequestMethod.PUT)
    public User updateUserInfo(@PathVariable("id") String id, @RequestBody User user) {
        user.setUserName("new");
        return user;
    }

    @Override
    @RequestMapping(value = "/user_update/map", method = RequestMethod.PUT)
    public User updateUserInfoByMap(@RequestBody Map map) {
        User user = new User();
        user.setUserName(map.get("name").toString());
        return user;
    }

    @Override
    @RequestMapping(value = "/user_create", method = RequestMethod.POST)
    public User createUserInfo(@RequestBody User user) {
        user.setUserName("new");
        return user;
    }

    @Override
    @RequestMapping(value = "/user_delete", method = RequestMethod.DELETE)
    public User deleteUserInfo(@RequestParam(value="id") String id) {
        User user = new User();
        user.setUserName("someone deleted");
        return user;
    }
}

客户端：

package com.zzhblh.sample;

import com.zzhblh.entity.account.User;
import org.springframework.http.*;
import org.springframework.web.client.RestTemplate;

import java.net.URI;
import java.util.HashMap;
import java.util.Map;

/**
 * Created by chen on 2016/9/2.
 */
public class testRest {

    static String REST_SERVICE_URI = "http://localhost:8080/practice-web/api/user_resource";

    private static void getUser(){
        System.out.println("Testing getUser API----------");
        RestTemplate restTemplate = new RestTemplate();
        User user = restTemplate.getForObject(REST_SERVICE_URI+"/user_query?id=123", User.class);
        System.out.println(user);
    }

    private static void updateUser(){
        System.out.println("Testing updateUser API----------");
        RestTemplate restTemplate = new RestTemplate();
        User user = new User("123","old");
        restTemplate.put(REST_SERVICE_URI+"/user_update/123", user, User.class);

        //使用resttemplate的put方法得不到返回值
        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.APPLICATION_JSON);
        HttpEntity<User> userRequest = new HttpEntity<User>(user, headers);
        ResponseEntity<User> responseEntity = restTemplate.exchange(REST_SERVICE_URI+"/user_update/123", HttpMethod.PUT, userRequest, User.class);
        System.out.println(responseEntity.getBody().toString());
    }

    private static void updateUserMap(){
        System.out.println("Testing updateUserMap API----------");
        RestTemplate restTemplate = new RestTemplate();
        Map map = new HashMap<String,String>();
        map.put("name","mm");
        restTemplate.put(REST_SERVICE_URI+"/user_update/map", map, Map.class);
    }

    /* POST */
    private static void createUser() {
        System.out.println("Testing create User API----------");
        RestTemplate restTemplate = new RestTemplate();
        User user = new User("123","old");
        user = restTemplate.postForObject(REST_SERVICE_URI+"/user_create", user, User.class);
        System.out.println(user.toString());

        ResponseEntity<User> responseEntity = restTemplate.postForEntity(REST_SERVICE_URI+"/user_create", user, User.class);
        System.out.println(responseEntity.getBody().toString());
    }

    /* DELETE */
    private static void deleteUser() {
        System.out.println("Testing delete User API----------");
        RestTemplate restTemplate = new RestTemplate();
        restTemplate.delete(REST_SERVICE_URI+"/user_delete?id=123");
        System.out.println("deleted");

        //使用resttemplate的put方法得不到返回值
        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.APPLICATION_JSON);
        HttpEntity<User> userRequest = new HttpEntity<User>(headers);
        ResponseEntity<User> responseEntity = restTemplate.exchange(REST_SERVICE_URI+"/user_delete", HttpMethod.DELETE, userRequest, User.class);
        System.out.println(responseEntity.getBody().toString());
    }

    public static void main(String args[]){
        getUser();
        updateUser();
        updateUserMap();
        createUser();
        deleteUser();
    }

}

使用@Controller：
服务端：

package com.citic.test.action;
import java.util.ArrayList;
import java.util.List;

import net.sf.json.JSONObject;

import org.apache.log4j.Logger;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;

import com.citic.test.entity.Person;

/**
 * 基于Restful风格架构测试
 * 
 * @author dekota
 * @since JDK1.5
 * @version V1.0
 * @history 2014-2-15 下午3:00:12 dekota 新建
 */
@Controller
@Scope("prototype")//改为多列模式
public class DekotaAction {

    /** 日志实例 */
    private static final Logger logger = Logger.getLogger(DekotaAction.class);

    @RequestMapping(value = "/hello", produces = "text/plain;charset=UTF-8")
    public @ResponseBody
    String hello() {
        return "你好！hello";
    }

    @RequestMapping(value = "/say/{msg}", produces = "application/json;charset=UTF-8")
    public @ResponseBody
    String say(@PathVariable(value = "msg") String msg) {
        return "{\"msg\":\"you say:'" + msg + "'\"}";
    }

    @RequestMapping(value = "/person/{id:\\d+}", method = RequestMethod.GET)
    public @ResponseBody
    Person getPerson(@PathVariable("id") int id) {
        logger.info("获取人员信息id=" + id);
        Person person = new Person();
        person.setName("张三");
        person.setSex("男");
        person.setAge(30);
        person.setId(id);
        return person;
    }

    @RequestMapping(value = "/person/{id:\\d+}", method = RequestMethod.DELETE)
    public @ResponseBody
    Object deletePerson(@PathVariable("id") int id) {
        logger.info("删除人员信息id=" + id);
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("msg", "删除人员信息成功");
        return jsonObject;
    }

    @RequestMapping(value = "/person", method = RequestMethod.POST)
    public @ResponseBody
    Object addPerson(Person person) {
        logger.info("注册人员信息成功id=" + person.getId());
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("msg", "注册人员信息成功");
        return jsonObject;
    }

    @RequestMapping(value = "/person", method = RequestMethod.PUT)
    public @ResponseBody
    Object updatePerson(Person person) {
        logger.info("更新人员信息id=" + person.getId());
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("msg", "更新人员信息成功");
        return jsonObject;
    }

    @RequestMapping(value = "/person", method = RequestMethod.PATCH)
    public @ResponseBody
    List<Person> listPerson(@RequestParam(value = "name", required = false, defaultValue = "") String name) {

        logger.info("查询人员name like " + name);
        List<Person> lstPersons = new ArrayList<Person>();

        Person person = new Person();
        person.setName("张三");
        person.setSex("男");
        person.setAge(25);
        person.setId(101);
        lstPersons.add(person);

        Person person2 = new Person();
        person2.setName("李四");
        person2.setSex("女");
        person2.setAge(23);
        person2.setId(102);
        lstPersons.add(person2);

        Person person3 = new Person();
        person3.setName("王五");
        person3.setSex("男");
        person3.setAge(27);
        person3.setId(103);
        lstPersons.add(person3);

        return lstPersons;
    }

}

客户端：

<script type="text/javascript">
    (function(window,$){
        var dekota={  
            url:'',
            init:function(){
                dekota.url='<%=basePath%>';
                $.UIkit.notify("页面初始化完成", {status:'info',timeout:500});
                $("#btnGet").click(dekota.getPerson);
                $("#btnAdd").click(dekota.addPerson);
                $("#btnDel").click(dekota.delPerson);
                $("#btnUpdate").click(dekota.updatePerson);
                $("#btnList").click(dekota.listPerson);
            },
            getPerson:function(){
                $.ajax({
                    url: dekota.url + 'person/101/',
                    type: 'GET',
                    dataType: 'json'
                }).done(function(data, status, xhr) {
                    $.UIkit.notify("获取人员信息成功", {status:'success',timeout:1000});
                }).fail(function(xhr, status, error) {
                    $.UIkit.notify("请求失败！", {status:'danger',timeout:2000});
                });
            },
            addPerson:function(){
                $.ajax({
                    url: dekota.url + 'person',
                    type: 'POST',
                    dataType: 'json',
                    data: {id: 1,name:'张三',sex:'男',age:23}
                }).done(function(data, status, xhr) {
                    $.UIkit.notify(data.msg, {status:'success',timeout:1000});
                }).fail(function(xhr, status, error) {
                    $.UIkit.notify("请求失败！", {status:'danger',timeout:2000});
                });
            },
            delPerson:function(){
                $.ajax({
                    url: dekota.url + 'person/109',
                    type: 'DELETE',
                    dataType: 'json'
                }).done(function(data, status, xhr) {
                    $.UIkit.notify(data.msg, {status:'success',timeout:1000});
                }).fail(function(xhr, status, error) {
                    $.UIkit.notify("请求失败！", {status:'danger',timeout:2000});
                });
            },
            updatePerson:function(){
                $.ajax({
                    url: dekota.url + 'person',
                    type: 'POST',//注意在传参数时，加：_method:'PUT'　将对应后台的PUT请求方法
                    dataType: 'json',
                    data: {_method:'PUT',id: 221,name:'王五',sex:'男',age:23}
                }).done(function(data, status, xhr) {
                    $.UIkit.notify(data.msg, {status:'success',timeout:1000});
                }).fail(function(xhr, status, error) {
                    $.UIkit.notify("请求失败！", {status:'danger',timeout:2000});
                });
            },
            listPerson:function(){
                $.ajax({
                    url: dekota.url + 'person',
                    type: 'POST',//注意在传参数时，加：_method:'PATCH'　将对应后台的PATCH请求方法
                    dataType: 'json',
                    data: {_method:'PATCH',name: '张三'}
                }).done(function(data, status, xhr) {
                    $.UIkit.notify("查询人员信息成功", {status:'success',timeout:1000});
                }).fail(function(xhr, status, error) {
                    $.UIkit.notify("请求失败！", {status:'danger',timeout:2000});
                });
            }
        };
        window.dekota=(window.dekota)?window.dekota:dekota;
        $(function(){
            dekota.init();
        });
    })(window,jQuery);

</script>

---

要点：服务端在类上加上@RestController注解。客户端请求时获取数据用GET,更新用PUT,创建用POST,删除用DELETE。

---

参考：
http://www.iteye.com/topic/1127120
http://websystique.com/springmvc/spring-mvc-4-restful-web-services-crud-example-resttemplate/
http://www.cnblogs.com/yjmyzz/p/javaee-jax-rs-tutorial.html
关于和jersey可参考：
http://waylau.com/categories/)