三种方法实现java调用Restful接口
转自：https://www.cnblogs.com/taozhiye/p/6704659.html
引言：当前，web开发中第三方接口的选择往往是在restful接口和web service 接口
web service接口的实现方式往往分为以下几种：
1.axis2框架
2.CXF框架
3.jdk
4.xfire
等，在这里只做记录，不再记录使用方式，需要的可以自行搜索
今天的重点是讲一讲更火的restful接口的常见实现方式：
HttpURLConnectionHttpClientSpring的RestTemplate
HttpURLConnection实现
@Controller
public class RestfulAction {
@Autowired
private 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";
}
}
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 {
@Autowired
private 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 nvps = new ArrayList();
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;
}
}
Spring的RestTemplate
springmvc.xml增加
@Controller
public class RestTemplateAction {
@Autowired
private 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 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 postParameters = new LinkedMultiValueMap();
postParameters.add("id", "啊啊啊");
postParameters.add("name", "部版本");
HttpEntity> requestEntity = new HttpEntity>(
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;
}
}