該工具類可以呼叫POST請求或者Get請求，引數以Map的方式傳入，支援獲獲取返回值，返回值接收型別為String

 HttpRequestUtil.java

package com.util;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.List;
import java.util.Map;

import net.sf.json.JSONObject;

/**
* 用於模擬HTTP請求中GET/POST方式
*
* @author https://www.mojxtang.club/
* @date 2017年8月24日
*/
public class HttpRequestUtil {
/**
* 傳送GET請求
*
* @param url 目的地址
* @param parameters 請求引數，Map型別。
* @return 遠端響應結果
*/
public static String sendGet(String url, Map<String, String> parameters) {
String result = "";
BufferedReader in = null;// 讀取響應輸入流
StringBuffer sb = new StringBuffer();// 儲存引數
String params = "";// 編碼之後的引數
try {
// 編碼請求引數
if (parameters.size() == 1) {
for (String name : parameters.keySet()) {
sb.append(name).append("=").append(java.net.URLEncoder.encode(parameters.get(name), "UTF-8"));
}
params = sb.toString();
} else {
for (String name : parameters.keySet()) {
sb.append(name).append("=").append(java.net.URLEncoder.encode(parameters.get(name), "UTF-8"))
.append("&");
}
String temp_params = sb.toString();
params = temp_params.substring(0, temp_params.length() - 1);
}
String full_url = url + "?" + params;
System.out.println(full_url);
// 建立URL物件
java.net.URL connURL = new java.net.URL(full_url);
// 開啟URL連線
java.net.HttpURLConnection httpConn = (java.net.HttpURLConnection) connURL.openConnection();
// 設定通用屬性
httpConn.setRequestProperty("Accept", "*/*");
httpConn.setRequestProperty("Connection", "Keep-Alive");
httpConn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1)");
// 建立實際的連線
httpConn.connect();
// 響應頭部獲取
Map<String, List<String>> headers = httpConn.getHeaderFields();
// 遍歷所有的響應頭欄位
for (String key : headers.keySet()) {
System.out.println(key + "\t：\t" + headers.get(key));
}
// 定義BufferedReader輸入流來讀取URL的響應,並設定編碼方式
in = new BufferedReader(new InputStreamReader(httpConn.getInputStream(), "UTF-8"));
String line;
// 讀取返回的內容
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (in != null) {
in.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
return result;
}

/**
* 傳送POST請求
*
* @param url 目的地址
* @param parameters 請求引數，Map型別。
* @return 遠端響應結果
*/
public static String sendPost(String url, Map<String, String> parameters) {
String result = "";// 返回的結果
BufferedReader in = null;// 讀取響應輸入流
PrintWriter out = null;
StringBuffer sb = new StringBuffer();// 處理請求引數
String params = "";// 編碼之後的引數
try {
// 編碼請求引數
if (parameters.size() == 1) {
for (String name : parameters.keySet()) {
sb.append(name).append("=").append(java.net.URLEncoder.encode(parameters.get(name), "UTF-8"));
}
params = sb.toString();
} else {
for (String name : parameters.keySet()) {
sb.append(name).append("=").append(java.net.URLEncoder.encode(parameters.get(name), "UTF-8"))
.append("&");
}
String temp_params = sb.toString();
params = temp_params.substring(0, temp_params.length() - 1);
}
// 建立URL物件
java.net.URL connURL = new java.net.URL(url);
// 開啟URL連線
java.net.HttpURLConnection httpConn = (java.net.HttpURLConnection) connURL.openConnection();
// 設定通用屬性
httpConn.setRequestProperty("Accept", "*/*");
httpConn.setRequestProperty("Connection", "Keep-Alive");
httpConn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1)");
// 設定POST方式
httpConn.setDoInput(true);
httpConn.setDoOutput(true);
// 獲取HttpURLConnection物件對應的輸出流
out = new PrintWriter(httpConn.getOutputStream());
// 傳送請求引數
out.write(params);
// flush輸出流的緩衝
out.flush();
// 定義BufferedReader輸入流來讀取URL的響應，設定編碼方式
in = new BufferedReader(new InputStreamReader(httpConn.getInputStream(), "UTF-8"));
String line;
// 讀取返回的內容
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (out != null) {
out.close();
}
if (in != null) {
in.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
return result;
}

public static String sendPostTest(String url, JSONObject json) {
String result = "";// 返回的結果
BufferedReader in = null;// 讀取響應輸入流
PrintWriter out = null;
String params = "";// 編碼之後的引數
try {
// 編碼請求引數
params = json.toString();
// 建立URL物件
java.net.URL connURL = new java.net.URL(url);
// 開啟URL連線
java.net.HttpURLConnection httpConn = (java.net.HttpURLConnection) connURL.openConnection();
// 設定通用屬性
httpConn.setRequestProperty("Accept", "*/*");
httpConn.setRequestProperty("Connection", "Keep-Alive");
httpConn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1)");
// 設定POST方式
httpConn.setDoInput(true);
httpConn.setDoOutput(true);
// 獲取HttpURLConnection物件對應的輸出流
out = new PrintWriter(httpConn.getOutputStream());
// 傳送請求引數
out.write(params);
// flush輸出流的緩衝
out.flush();
// 定義BufferedReader輸入流來讀取URL的響應，設定編碼方式
in = new BufferedReader(new InputStreamReader(httpConn.getInputStream(), "UTF-8"));
String line;
// 讀取返回的內容
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (out != null) {
out.close();
}
if (in != null) {
in.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
return result;
}
}

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