后端实现调用其他系统Restful接口服务
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) restServiceURL
44 .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 nvps = new ArrayList();
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 2 35 8 9 106 7 11 12
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 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 postParameters = new LinkedMultiValueMap();
28 postParameters.add("id", "啊啊啊");
29 postParameters.add("name", "部版本");
30 HttpEntity> requestEntity = new HttpEntity>(
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 }