后端实现调用其他系统Restful接口服务

来源：互联网发布：java多线程项目实例编辑：程序博客网时间：2024/05/22 06:28

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

 1 @Controller 2 public class RestfulAction { 3      4     @Autowired 5     private UserService userService; 6  7     // 修改 8     @RequestMapping(value = "put/{param}", method = RequestMethod.PUT) 9     public @ResponseBody String put(@PathVariable String param) {10         return "put:" + param;11     }12 13     // 新增14     @RequestMapping(value = "post/{param}", method = RequestMethod.POST)15     public @ResponseBody String post(@PathVariable String param,String id,String name) {16         System.out.println("id:"+id);17         System.out.println("name:"+name);18         return "post:" + param;19     }20     21 22     // 删除23     @RequestMapping(value = "delete/{param}", method = RequestMethod.DELETE)24     public @ResponseBody String delete(@PathVariable String param) {25         return "delete:" + param;26     }27 28     // 查找29     @RequestMapping(value = "get/{param}", method = RequestMethod.GET)30     public @ResponseBody String get(@PathVariable String param) {31         return "get:" + param;32     }33     34     35     // HttpURLConnection 方式调用Restful接口36     // 调用接口37     @RequestMapping(value = "dealCon/{param}")38     public @ResponseBody String dealCon(@PathVariable String param) {39         try {40             String url = "http://localhost:8080/tao-manager-web/";41             url+=(param+"/xxx");42             URL restServiceURL = new URL(url);43             HttpURLConnection httpConnection = (HttpURLConnection) restServiceURL44                     .openConnection();45             //param 输入小写，转换成 GET POST DELETE PUT 46             httpConnection.setRequestMethod(param.toUpperCase());47 //            httpConnection.setRequestProperty("Accept", "application/json");48             if("post".equals(param)){49                 //打开输出开关50                 httpConnection.setDoOutput(true);51 //                httpConnection.setDoInput(true);52                 53                 //传递参数54                 String input = "&id="+ URLEncoder.encode("abc", "UTF-8");55                 input+="&name="+ URLEncoder.encode("啊啊啊", "UTF-8");56                 OutputStream outputStream = httpConnection.getOutputStream();57                 outputStream.write(input.getBytes());58                 outputStream.flush();59             }60             if (httpConnection.getResponseCode() != 200) {61                 throw new RuntimeException(62                         "HTTP GET Request Failed with Error code : "63                                 + httpConnection.getResponseCode());64             }65             BufferedReader responseBuffer = new BufferedReader(66                     new InputStreamReader((httpConnection.getInputStream())));67             String output;68             System.out.println("Output from Server:  \n");69             while ((output = responseBuffer.readLine()) != null) {70                 System.out.println(output);71             }72             httpConnection.disconnect();73         } catch (MalformedURLException e) {74             e.printStackTrace();75         } catch (IOException e) {76             e.printStackTrace();77         }78         return "success";79     }80 81 }

3.HttpClient实现

  1 package com.taozhiye.controller;  2   3 import org.apache.http.HttpEntity;  4 import org.apache.http.HttpResponse;  5 import org.apache.http.NameValuePair;  6 import org.apache.http.client.HttpClient;  7 import org.apache.http.client.entity.UrlEncodedFormEntity;  8 import org.apache.http.client.methods.HttpDelete;  9 import org.apache.http.client.methods.HttpGet; 10 import org.apache.http.client.methods.HttpPost; 11 import org.apache.http.client.methods.HttpPut; 12 import org.apache.http.impl.client.HttpClients; 13 import org.apache.http.message.BasicNameValuePair; 14 import org.springframework.beans.factory.annotation.Autowired; 15 import org.springframework.stereotype.Controller; 16 import org.springframework.web.bind.annotation.PathVariable; 17 import org.springframework.web.bind.annotation.RequestMapping; 18 import org.springframework.web.bind.annotation.RequestMethod; 19 import org.springframework.web.bind.annotation.ResponseBody; 20  21 import com.fasterxml.jackson.databind.ObjectMapper; 22 import com.taozhiye.entity.User; 23 import com.taozhiye.service.UserService; 24  25 import java.io.BufferedReader; 26 import java.io.IOException; 27 import java.io.InputStreamReader; 28 import java.io.OutputStream; 29 import java.net.HttpURLConnection; 30 import java.net.MalformedURLException; 31 import java.net.URL; 32 import java.net.URLEncoder; 33 import java.util.ArrayList; 34 import java.util.List; 35  36 @Controller 37 public class RestfulAction { 38      39     @Autowired 40     private UserService userService; 41  42     // 修改 43     @RequestMapping(value = "put/{param}", method = RequestMethod.PUT) 44     public @ResponseBody String put(@PathVariable String param) { 45         return "put:" + param; 46     } 47  48     // 新增 49     @RequestMapping(value = "post/{param}", method = RequestMethod.POST) 50     public @ResponseBody User post(@PathVariable String param,String id,String name) { 51         User u = new User(); 52         System.out.println(id); 53         System.out.println(name); 54         u.setName(id); 55         u.setPassword(name); 56         u.setEmail(id); 57         u.setUsername(name); 58         return u; 59     } 60      61  62     // 删除 63     @RequestMapping(value = "delete/{param}", method = RequestMethod.DELETE) 64     public @ResponseBody String delete(@PathVariable String param) { 65         return "delete:" + param; 66     } 67  68     // 查找 69     @RequestMapping(value = "get/{param}", method = RequestMethod.GET) 70     public @ResponseBody User get(@PathVariable String param) { 71         User u = new User(); 72         u.setName(param); 73         u.setPassword(param); 74         u.setEmail(param); 75         u.setUsername("爱爱啊"); 76         return u; 77     } 78  79      80      81     @RequestMapping(value = "dealCon2/{param}") 82     public @ResponseBody User dealCon2(@PathVariable String param) { 83         User user = null; 84         try { 85             HttpClient client = HttpClients.createDefault(); 86             if("get".equals(param)){ 87                 HttpGet request = new HttpGet("http://localhost:8080/tao-manager-web/get/" 88                         +"啊啊啊"); 89                 request.setHeader("Accept", "application/json"); 90                 HttpResponse response = client.execute(request); 91                 HttpEntity entity = response.getEntity(); 92                 ObjectMapper mapper = new ObjectMapper(); 93                 user = mapper.readValue(entity.getContent(), User.class); 94             }else if("post".equals(param)){ 95                 HttpPost request2 = new HttpPost("http://localhost:8080/tao-manager-web/post/xxx"); 96                 List<NameValuePair> nvps = new ArrayList<NameValuePair>();   97                 nvps.add(new BasicNameValuePair("id", "啊啊啊"));   98                 nvps.add(new BasicNameValuePair("name", "secret")); 99                 UrlEncodedFormEntity formEntity = new UrlEncodedFormEntity(nvps, "GBK");100                 request2.setEntity(formEntity);101                 HttpResponse response2 = client.execute(request2);102                 HttpEntity entity = response2.getEntity();103                 ObjectMapper mapper = new ObjectMapper();104                 user = mapper.readValue(entity.getContent(), User.class);105             }else if("delete".equals(param)){106                 107             }else if("put".equals(param)){108                 109             }110         } catch (Exception e) {111             e.printStackTrace();112         }113         return user;114     }115     116     117 }

4.Spring的RestTemplate

springmvc.xml增加

 1     <!-- 配置RestTemplate --> 2     <!--Http client Factory --> 3     <bean id="httpClientFactory" 4         class="org.springframework.http.client.SimpleClientHttpRequestFactory"> 5         <property name="connectTimeout" value="10000" /> 6         <property name="readTimeout" value="10000" /> 7     </bean> 8  9     <!--RestTemplate -->10     <bean id="restTemplate" class="org.springframework.web.client.RestTemplate">11         <constructor-arg ref="httpClientFactory" />12     </bean>

controller

 1 @Controller 2 public class RestTemplateAction { 3  4     @Autowired 5     private RestTemplate template; 6  7     @RequestMapping("RestTem") 8     public @ResponseBody User RestTem(String method) { 9         User user = null;10         //查找11         if ("get".equals(method)) {12             user = template.getForObject(13                     "http://localhost:8080/tao-manager-web/get/{id}",14                     User.class, "呜呜呜呜");15             16             //getForEntity与getForObject的区别是可以获取返回值和状态、头等信息17             ResponseEntity<User> re = template.18                     getForEntity("http://localhost:8080/tao-manager-web/get/{id}",19                     User.class, "呜呜呜呜");20             System.out.println(re.getStatusCode());21             System.out.println(re.getBody().getUsername());22             23         //新增24         } else if ("post".equals(method)) {25             HttpHeaders headers = new HttpHeaders();26             headers.add("X-Auth-Token", UUID.randomUUID().toString());27             MultiValueMap<String, String> postParameters = new LinkedMultiValueMap<String, String>();28             postParameters.add("id", "啊啊啊");29             postParameters.add("name", "部版本");30             HttpEntity<MultiValueMap<String, String>> requestEntity = new HttpEntity<MultiValueMap<String, String>>(31                     postParameters, headers);32             user = template.postForObject(33                     "http://localhost:8080/tao-manager-web/post/aaa", requestEntity,34                     User.class);35         //删除36         } else if ("delete".equals(method)) {37             template.delete("http://localhost:8080/tao-manager-web/delete/{id}","aaa");38         //修改39         } else if ("put".equals(method)) {40             template.put("http://localhost:8080/tao-manager-web/put/{id}",null,"bbb");41         }42         return user;43 44     }45 }

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