1,基本介绍

Restful接口的调用，前端一般使用ajax调用，后端可以使用的方法比较多，

　　本次介绍三种：

　　　　1.HttpURLConnection实现

　　　　2.HttpClient实现

　　　　3.Spring的RestTemplate

2，HttpURLConnection实现

@Controller
public class RestfulAction {@Autowiredprivate UserService userService;// 修改@RequestMapping(value = "put/{param}", method = RequestMethod.PUT)public @ResponseBody String put(@PathVariable String param) {return "put:" + param;}// 新增@RequestMapping(value = "post/{param}", method = RequestMethod.POST)public @ResponseBody String post(@PathVariable String param,String id,String name) {System.out.println("id:"+id);System.out.println("name:"+name);return "post:" + param;}// 删除@RequestMapping(value = "delete/{param}", method = RequestMethod.DELETE)public @ResponseBody String delete(@PathVariable String param) {return "delete:" + param;}// 查找@RequestMapping(value = "get/{param}", method = RequestMethod.GET)public @ResponseBody String get(@PathVariable String param) {return "get:" + param;}// HttpURLConnection 方式调用Restful接口// 调用接口@RequestMapping(value = "dealCon/{param}")public @ResponseBody String dealCon(@PathVariable String param) {try {String url = "http://localhost:8080/tao-manager-web/";url+=(param+"/xxx");URL restServiceURL = new URL(url);HttpURLConnection httpConnection = (HttpURLConnection) restServiceURL.openConnection();//param 输入小写，转换成 GET POST DELETE PUT httpConnection.setRequestMethod(param.toUpperCase());
//            httpConnection.setRequestProperty("Accept", "application/json");if("post".equals(param)){//打开输出开关httpConnection.setDoOutput(true);
//                httpConnection.setDoInput(true);//传递参数String input = "&id="+ URLEncoder.encode("abc", "UTF-8");input+="&name="+ URLEncoder.encode("啊啊啊", "UTF-8");OutputStream outputStream = httpConnection.getOutputStream();outputStream.write(input.getBytes());outputStream.flush();}if (httpConnection.getResponseCode() != 200) {throw new RuntimeException("HTTP GET Request Failed with Error code : "+ httpConnection.getResponseCode());}BufferedReader responseBuffer = new BufferedReader(new InputStreamReader((httpConnection.getInputStream())));String output;System.out.println("Output from Server:  \n");while ((output = responseBuffer.readLine()) != null) {System.out.println(output);}httpConnection.disconnect();} catch (MalformedURLException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}return "success";}
}

3.HttpClient实现

package com.taozhiye.controller;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpDelete;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpPut;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.springframework.beans.factory.annotation.Autowired;
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.ResponseBody;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.taozhiye.entity.User;
import com.taozhiye.service.UserService;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;@Controller
public class RestfulAction {  @Autowiredprivate UserService userService;// 修改@RequestMapping(value = "put/{param}", method = RequestMethod.PUT)public @ResponseBody String put(@PathVariable String param) {return "put:" + param;}// 新增@RequestMapping(value = "post/{param}", method = RequestMethod.POST)public @ResponseBody User post(@PathVariable String param,String id,String name) {User u = new User();System.out.println(id);System.out.println(name);u.setName(id);u.setPassword(name);u.setEmail(id);u.setUsername(name);return u;}    // 删除@RequestMapping(value = "delete/{param}", method = RequestMethod.DELETE)public @ResponseBody String delete(@PathVariable String param) {return "delete:" + param;}// 查找@RequestMapping(value = "get/{param}", method = RequestMethod.GET)public @ResponseBody User get(@PathVariable String param) {User u = new User();u.setName(param);u.setPassword(param);u.setEmail(param);u.setUsername("爱爱啊");return u;}@RequestMapping(value = "dealCon2/{param}")public @ResponseBody User dealCon2(@PathVariable String param) {User user = null;try {HttpClient client = HttpClients.createDefault();if("get".equals(param)){HttpGet request = new HttpGet("http://localhost:8080/tao-manager-web/get/"+"啊啊啊");request.setHeader("Accept", "application/json");HttpResponse response = client.execute(request);HttpEntity entity = response.getEntity();ObjectMapper mapper = new ObjectMapper();user = mapper.readValue(entity.getContent(), User.class);}else if("post".equals(param)){HttpPost request2 = new HttpPost("http://localhost:8080/tao-manager-web/post/xxx");List<NameValuePair> nvps = new ArrayList<NameValuePair>();  nvps.add(new BasicNameValuePair("id", "啊啊啊"));  nvps.add(new BasicNameValuePair("name", "secret"));UrlEncodedFormEntity formEntity = new UrlEncodedFormEntity(nvps, "GBK");request2.setEntity(formEntity);HttpResponse response2 = client.execute(request2);HttpEntity entity = response2.getEntity();ObjectMapper mapper = new ObjectMapper();user = mapper.readValue(entity.getContent(), User.class);}else if("delete".equals(param)){}else if("put".equals(param)){}} catch (Exception e) {e.printStackTrace();}return user;} 
}

4.Spring的RestTemplate

springmvc.xml增加

<!-- 配置RestTemplate --><!--Http client Factory --><bean id="httpClientFactory"class="org.springframework.http.client.SimpleClientHttpRequestFactory"><property name="connectTimeout" value="10000" /><property name="readTimeout" value="10000" /></bean><!--RestTemplate --><bean id="restTemplate" class="org.springframework.web.client.RestTemplate"><constructor-arg ref="httpClientFactory" /></bean>

controller

@Controller
public class RestTemplateAction {@Autowiredprivate RestTemplate template;@RequestMapping("RestTem")public @ResponseBody User RestTem(String method) {User user = null;//查找if ("get".equals(method)) {user = template.getForObject("http://localhost:8080/tao-manager-web/get/{id}",User.class, "呜呜呜呜");//getForEntity与getForObject的区别是可以获取返回值和状态、头等信息ResponseEntity<User> re = template.getForEntity("http://localhost:8080/tao-manager-web/get/{id}",User.class, "呜呜呜呜");System.out.println(re.getStatusCode());System.out.println(re.getBody().getUsername());//新增} else if ("post".equals(method)) {HttpHeaders headers = new HttpHeaders();headers.add("X-Auth-Token", UUID.randomUUID().toString());MultiValueMap<String, String> postParameters = new LinkedMultiValueMap<String, String>();postParameters.add("id", "啊啊啊");postParameters.add("name", "部版本");HttpEntity<MultiValueMap<String, String>> requestEntity = new HttpEntity<MultiValueMap<String, String>>(postParameters, headers);user = template.postForObject("http://localhost:8080/tao-manager-web/post/aaa", requestEntity,User.class);//删除} else if ("delete".equals(method)) {template.delete("http://localhost:8080/tao-manager-web/delete/{id}","aaa");//修改} else if ("put".equals(method)) {template.put("http://localhost:8080/tao-manager-web/put/{id}",null,"bbb");}return user;}
}

转载引用原地址