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JAR包依赖

本项目依赖以下JAR包：

工具类

import net.sf.json.JSONObject;import org.apache.http.HttpEntity;import org.apache.http.HttpStatus;import org.apache.http.NameValuePair;import org.apache.http.client.methods.HTTPGet;import org.apache.http.client.methods.HTTPPost;import org.apache.http.client.utils.URLEncodedUtils;import org.apache.http.entity.StringEntity;import org.apache.http.impl.client.CloseableHttpClient;import org.apache.http.impl.client.HttpClients;import org.apache.http.message.BasicNameValuePair;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.net.URI;import java.util.ArrayList;import java.util.List;import java.util.Map;import java.util.Set;/** * @Author: Administrator * @Description: 调用HTTP请求 * @Date: 2019-09-03 10:36 */public class HttpclientUtil {    /***     * post请求     * @param json 请求参数     * @param url 请求地址     * @return 结果     */    public static String post(JSONObject json, String url) {        String result = "";        HttpPost post = new HttpPost(url);        try {            CloseableHttpClient httpClient = HttpClients.createDefault();            post.setHeader("Content-Type", "application/json;charset=utf-8");            post.addHeader("Authorization", "Basic YWRtaW46");            StringEntity postingString = new StringEntity(json.toString(), "utf-8");            post.setEntity(postingString);            HttpResponse response = httpClient.execute(post);            InputStream in = response.getEntity().getContent();            BufferedReader br = new BufferedReader(new InputStreamReader(in, "utf-8"));            StringBuilder strber = new StringBuilder();            String line = null;            while ((line = br.readLine()) != null) {                strber.append(line + '\n');            }            br.close();            in.close();            result = strber.toString();            if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) {                result = "服务器异常";            }        } catch (Exception e) {            System.out.println("请求异常");            e.printStackTrace();            throw new RuntimeException(e);        } finally {            post.abort();        }        return result;    }    /***     * get无参请求     * @param url 请求地址     * @return 结果     */    public static String getHttp(String url) {        String result = "";        HttpGet get = new HttpGet(url);        try {            CloseableHttpClient httpClient = HttpClients.createDefault();            HttpResponse response = httpClient.execute(get);            result = getHttpEntityContent(response);            if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) {                result = "服务器异常";            }        } catch (Exception e) {            System.out.println("请求异常");            throw new RuntimeException(e);        } finally {            get.abort();        }        return result;    }    /***     * get有参请求     * @param paramMap 请求参数     * @param url 请求地址     * @return 结果     */    public static String get(Map
   
     paramMap, String url) {        String result = "";        HttpGet get = new HttpGet(url);        try {            CloseableHttpClient httpClient = HttpClients.createDefault();            List
    
      params = setHttpParams(paramMap);            String param = URLEncodedUtils.format(params, "UTF-8");            get.setURI(URI.create(url + "?" + param));            HttpResponse response = httpClient.execute(get);            result = getHttpEntityContent(response);            if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) {                result = "服务器异常";            }        } catch (Exception e) {            System.out.println("请求异常");            throw new RuntimeException(e);        } finally {            get.abort();        }        return result;    }    /***     * 拼接请求参数     * @param paramMap 请求参数     * @return 拼接后的请求参数列表     */    public static List
     
       setHttpParams(Map
      
        paramMap) {        List
       
         params = new ArrayList<>();        for (Map.Entry
        
          entry : paramMap.entrySet()) { params.add(new BasicNameValuePair(entry.getKey(), entry.getValue())); } return params; } /** * 获取HTTP实体内容 * @param response HTTP响应 * @return 实体内容字符串 * @throws UnsupportedOperationException * @throws IOException */ public static String getHttpEntityContent(HttpResponse response) throws UnsupportedOperationException, IOException { String result = ""; HttpEntity entity = response.getEntity(); if (entity != null) { InputStream in = entity.getContent(); BufferedReader br = new BufferedReader(new InputStreamReader(in, "utf-8")); StringBuilder strber = new StringBuilder(); String line = null; while ((line = br.readLine()) != null) { strber.append(line + '\n'); } br.close(); in.close(); result = strber.toString(); } return result; }}
        
       
      
     
    
   

测试类

import net.sf.json.JSONObject;import java.util.HashMap;/** * @Author: Administrator * @Description: 测试HTTP请求 * @Date: 2019-09-03 11:15 */public class HttpClientTest {    public static void main(String[] args) {        // 测试无参GET请求        String result1 = HttpclientUtil.getHttp("http://localhost:8080/web/testController/getHttp");        System.out.println("[测试无参GET请求] 返回的结果为：" + result1);        // 测试有参GET请求        HashMap
   
     hashMap = new HashMap<>();        hashMap.put("phone", "123456789");        String result2 = HttpclientUtil.get(hashMap, "http://localhost:8080/web/testController/testHttp");        System.out.println("[测试有参GET请求] 返回的结果为：" + result2);        // 测试有参POST请求        JSONObject jsonObject = new JSONObject();        jsonObject.put("phone", "987654321");        String result3 = HttpclientUtil.post(jsonObject, "http://localhost:8080/web/testController/testHttpPost");        System.out.println("[测试有参POST请求] 返回的结果为：" + result3);    }}
   

Controller接口类

import java.util.HashMap;import javax.servlet.http.HttpServletRequest;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.stereotype.Controller;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.alibaba.fastjson.JSONObject;/** * 测试Controller * @author Administrator */@RequestMapping("/testController")@Controllerpublic class TestController {    private static final Logger logger = LoggerFactory.getLogger(TestController.class);    /**     * 测试GET无参请求     */    @RequestMapping("/getHttp")    @ResponseBody    public String getHttp() {        logger.info("调用无参请求成功");        return "Hello World!";    }    /**     * 测试GET有参请求     */    @RequestMapping("/testHttp")    @ResponseBody    public String testHttp(HttpServletRequest request) {        // 获取参数        logger.info("获取参数为：" + ControllerUtil.getParamMap(request));        HashMap
   
     resultMap = new HashMap<>();        String phone = (String) ControllerUtil.getParamMap(request).get("phone");        if (phone.equals("123456789")) {            resultMap.put("name", "张三");            resultMap.put("age", "25");            resultMap.put("profession", "JAVA");        } else {            resultMap.put("name", "李四");            resultMap.put("age", "27");            resultMap.put("profession", "PYTHON");        }        return JSONObject.toJSONString(resultMap);    }    /**     * 测试POST有参请求     */    @RequestMapping(value = "/testHttpPost", method = {RequestMethod.POST}, produces = "application/json;charset=UTF-8")    @ResponseBody    public String testHttpPost(HttpServletRequest request) {        // 获取参数        String phone = request.getParameter("phone");        // 获取参数        HashMap
    
      resultMap = new HashMap<>();        if (phone.equals("123456789")) {            resultMap.put("name", "张三");            resultMap.put("age", "25");            resultMap.put("profession", "JAVA");        } else {            resultMap.put("name", "李四");            resultMap.put("age", "27");            resultMap.put("profession", "PYTHON");        }        return JSONObject.toJSONString(resultMap);    }}
    
   

前台参数拼接工具类

import java.util.Enumeration;import java.util.HashMap;import java.util.Iterator;import java.util.Map;import java.util.Set;import java.util.concurrent.ConcurrentHashMap;import javax.servlet.http.HttpServletRequest;import net.sf.json.JSONArray;/** * 参数拼接工具类 */public class ControllerUtil {    /**     * 拼装列表返回结果     * @param total 总数     * @param page 当前页     * @param pagesize 每页数量     * @param jsonResult JSON结果     * @return 拼装后的JSON结果     */    public static Map
   
     getReturnMap(int total, String page, String pagesize, String jsonResult) {        Map
    
      map = new HashMap<>();        map.put("total", String.valueOf(total));        map.put("page", String.valueOf(Integer.parseInt(page) * Integer.parseInt(pagesize)));        map.put("pagesize", pagesize);        map.put("rows", JSONArray.fromObject(jsonResult));        return map;    }    /**     * 拼装包含分页信息的JSON结果     * @param jsonResult JSON结果     * @return 拼装后的JSON结果     */    public static Map
     
       getReturnMapWithFooter(String jsonResult) {        Map
      
        map = new ConcurrentHashMap<>();        map.put("rows", JSONArray.fromObject(jsonResult));        return map;    }    /**     * 拼接查询参数     * @param request 请求对象     * @return 拼接后的参数Map     */    public static HashMap
       
         getParamMap(HttpServletRequest request) {        HashMap
        
          paramMap = new HashMap<>(); Enumeration
         
           pNames = request.getParameterNames(); while (pNames.hasMoreElements()) { String name = (String) pNames.nextElement(); String value = request.getParameter(name); if (name.equals("page")) { value = String.valueOf(Integer.parseInt(value) * 10); } paramMap.put(name, value); } return paramMap; } /** * 拼接查询参数 * @param request 请求对象 * @return 拼接后的参数Map */ public static HashMap
          
            getParamsMap(HttpServletRequest request) { String pageSize = request.getParameter("pagesize"); Enumeration
           
             pNames = request.getParameterNames(); HashMap
            
              paramMap = new HashMap<>(); while (pNames.hasMoreElements()) { String name = (String) pNames.nextElement(); String value = request.getParameter(name); if (name.equals("page")) { value = String.valueOf(Integer.parseInt(value) * Integer.parseInt(pageSize)); } paramMap.put(name, value); } return paramMap; }}