java调用GET\POST发送GET/POST请求的工具类

写在前面
很多时候我们需要去调用或者发送请求访问java的rest接口，这时候一般我们项目组会添加相对应的工具类进行封装，不用每次都去重新写一次，类似于java的jdbc，我们如果使用mabits时候，框架已经为我们封装好相关的代码，这也是java面向对象的编程思想的体现，这里就没太多的文字概述啦~~
直接上代码，有需要的小伙伴可以直接复制到自己的工具类中使用哦
改工具类名称：RestUtil.java

package com.cn.zhangb.util;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.URL;

import net.sf.json.JSONObject;

public class RestUtil {

	/**
	 * 发送get请求到rest接口
	 */
	public static String sendgetMethod(String url) throws IOException {
		StringBuffer string = new StringBuffer();
		BufferedReader rd = null;
		String line = null;
		try {
			URL restServiceURL = new URL(url);
			HttpURLConnection conn = (HttpURLConnection)restServiceURL.openConnection();
			conn.setRequestMethod("GET");
			conn.setRequestProperty("Accept", "application/json");
			conn.setDoInput(true);
			conn.setUseCaches(false);
			if(conn.getResponseCode() != 200){
				throw new RuntimeException("HTTP POST Request Failed with Error code :"
						+ conn.getResponseCode());
			}
			InputStream inStrm = conn.getInputStream();
			rd = new BufferedReader(new InputStreamReader(inStrm,"UTF-8"));
			while ((line = rd.readLine()) != null){
				string.append(line);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		return string.toString();
	}
	  /**
	   * get 请求调用方法
	   * @param url
	   * @return
	   * @throws IOException
	   */
	  public static String getMethod(String url) throws IOException {
		  StringBuffer string = new StringBuffer();
			try {
				URL restServiceURL = new URL(url);
				HttpURLConnection httpURLConnection = (HttpURLConnection)restServiceURL.openConnection();
				httpURLConnection.setRequestMethod("GET");
				httpURLConnection.setRequestProperty("Accept", "application/json");
				httpURLConnection.setDoInput(true);
				httpURLConnection.setUseCaches(false);
				if(httpURLConnection.getResponseCode() != 200){
					throw new RuntimeException("HTTP POST Request Failed with Error code :"
							+ httpURLConnection.getResponseCode());
				}
				InputStream inStrm = httpURLConnection.getInputStream();
				byte[] b =new byte[1024];
				int length = -1;
				while((length = inStrm.read(b)) != -1){
					string.append(new String(b,0,length));
				}
			} catch (Exception e) {
				e.printStackTrace();
			}
		    return string.toString();
	  }
	 
	  /**
	   * Post调用方法   
	   * @param url
	   * @param json
	   * @return
	   * @throws IOException
	   */
	  public static String postMethod(String url, JSONObject json) throws IOException {
		StringBuffer string = new StringBuffer();
		try {
			URL restServiceURL = new URL(url);
			
			HttpURLConnection httpURLConnection = (HttpURLConnection)restServiceURL.openConnection();
			httpURLConnection.setRequestMethod("POST");
			httpURLConnection.setRequestProperty("Accept", "application/json");
			httpURLConnection.setDoInput(true);
			httpURLConnection.setUseCaches(false);
			if(httpURLConnection.getResponseCode() != 200){
				throw new RuntimeException("HTTP POST Request Failed with Error code :"
						+ httpURLConnection.getResponseCode());
			}
			InputStream inStrm = httpURLConnection.getInputStream();
			byte[] b =new byte[1024];
			int length = -1;
			while((length = inStrm.read(b)) != -1){
				string.append(new String(b,0,length));
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	    return string.toString();
	  }
	  
	  public static String postJsonMethod(String url, JSONObject data){
			StringBuffer result = null;
			String json = "";
			if(data == null){
				json = "{}";
			}else{
				json = data.toString();
			}
			HttpURLConnection conn = null;
			OutputStreamWriter out = null;
			BufferedReader reader = null;
			try {
				URL realUrl = new URL(url);
				result = new StringBuffer();
				conn = (HttpURLConnection) realUrl.openConnection();
				conn.setRequestMethod("POST");
				conn.setRequestProperty("Content-Type", "application/json");
				conn.setRequestProperty("connection", "keep-alive");
				conn.setRequestProperty("Accept", "application/json");
				conn.setUseCaches(false);
				conn.setInstanceFollowRedirects(true);
				conn.setDoOutput(true);
				conn.setDoInput(true);
				conn.setConnectTimeout(5000);
				conn.setReadTimeout(5000);
				//POST请求
				out = new OutputStreamWriter(conn.getOutputStream());
				out.write(json);
				out.flush();
				
				//读取响应
				reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
				String lines = null;
				while ((lines = reader.readLine()) != null){
					lines = new String(lines.getBytes());
					result.append(lines);
				}
				reader.close();
				conn.disconnect();
			}  catch (Exception e) {
				System.out.println("发送POST请求出现异常!" + e);
				e.printStackTrace();
			} finally {
				try {
					if(out != null){
						out.close();
					}
					if(reader != null){
						reader.close();
					}
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			
			return result.toString();
		}
	  /**
	   * 发送HttpPost请求
	   * @param url  请求URL
	   * @param param url 请求参数
	   * @return 请求响应结果
	   */
	  public static String sendPost(String url,String param) {
		  StringBuffer result = null;
			HttpURLConnection conn = null;
			PrintWriter out = null;
			BufferedReader reader = null;
			try {
				URL realUrl = new URL(url);
				result = new StringBuffer();
				conn = (HttpURLConnection) realUrl.openConnection();
				conn.setRequestProperty("accept", "*/*");
				conn.setRequestProperty("connection", "Keep-Alive");
				conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");

	/*			conn.setRequestMethod("POST");
				conn.setRequestProperty("Content-Type", "application/json");
				conn.setRequestProperty("connection", "keep-alive");
				conn.setRequestProperty("Accept", "application/json");
				conn.setUseCaches(false);
				conn.setInstanceFollowRedirects(true);*/
				conn.setDoOutput(true);
				conn.setDoInput(true);
				
				//POST请求
				out = new PrintWriter(conn.getOutputStream());
				out.print(param);
				out.flush();
				
				
				//读取响应
				reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
				String lines = null;
				while ((lines = reader.readLine()) != null){
					lines = new String(lines.getBytes());
					result.append(lines);
				}
				//reader.close();
				//conn.disconnect();
			}  catch (Exception e) {
				System.out.println("发送POST请求出现异常!" + e);
				e.printStackTrace();
			} finally {
				try {
					if(out != null){
						out.close();
					}
					if(reader != null){
						reader.close();
					}
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			
			return result.toString();
	  }

	 
	}

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