java发送post 的json请求

package com.elink.estos.mq.mqmanager;

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

public class JavaPostJson2 {
    final static String url = "http://localhost:1111/sendData";
    final static String params = "{\"token\":\"12345\","
            + "\"appId\":\"20180628173051169c85d965d164ed9ab1281d22ff350ec19\"" + "\"appName\":\"test33\""
            + "\"classTopic\":\"112\"" + "\"eventTag\":\"22\"" + "}";

    public static void main(String[] args) {

        String res = post(url, params);
        System.out.println(res);

    }

    /**
     * 发送HttpPost请求
     * 
     * @param strURL
     *            服务地址
     * @param params
     *            json字符串,例如: "{ \"id\":\"12345\" }" ;其中属性名必须带双引号<br/>
     * @return 成功:返回json字符串<br/>
     */
    public static String post(String strURL, String params) {
        System.out.println(strURL);
        System.out.println(params);
        BufferedReader reader = null;
        try {
            URL url = new URL(strURL);// 创建连接
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setDoOutput(true);
            connection.setDoInput(true);
            connection.setUseCaches(false);
            connection.setInstanceFollowRedirects(true);
            connection.setRequestMethod("POST"); // 设置请求方式
            // connection.setRequestProperty("Accept", "application/json"); // 设置接收数据的格式
            connection.setRequestProperty("Content-Type", "application/json"); // 设置发送数据的格式
            connection.connect();
            //一定要用BufferedReader 来接收响应， 使用字节来接收响应的方法是接收不到内容的
            OutputStreamWriter out = new OutputStreamWriter(connection.getOutputStream(), "UTF-8"); // utf-8编码
            out.append(params);
            out.flush();
            out.close();
            // 读取响应
            reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), "UTF-8"));
            String line;
            String res = "";
            while ((line = reader.readLine()) != null) {
                res += line;
            }
            reader.close();
            
            //如果一定要使用如下方式接收响应数据， 则响应必须为: response.getWriter().print(StringUtils.join("{\"errCode\":\"1\",\"errMsg\":\"", message, "\"}")); 来返回
//            int length = (int) connection.getContentLength();// 获取长度
//            if (length != -1) {
//                byte[] data = new byte[length];
//                byte[] temp = new byte[512];
//                int readLen = 0;
//                int destPos = 0;
//                while ((readLen = is.read(temp)) > 0) {
//                    System.arraycopy(temp, 0, data, destPos, readLen);
//                    destPos += readLen;
//                }
//                String result = new String(data, "UTF-8"); // utf-8编码
//                System.out.println(result);
//                return result;
//            }

            return res;
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return "error"; // 自定义错误信息
    }

}

import java.io.IOException;import java.io.InputStream;import java.io.OutputStreamWriter;import java.net.HttpURLConnection;import java.net.URL;import java.io.BufferedReader;import java.io.InputStreamReader;
public class JavaPostJson2 {final static String url = "http://localhost:1111/sendData";// final static String params = "{\"token\":\"12345\","// + "\"appId\":\"20180628173051169c85d965d164ed9ab1281d22ff350ec19\"" // + "\"appName\":\"test33\""// + "\"classTopic\":\"112\"" // + "\"eventTag\":\"22\"" // + "\"msg\":{}"// + "}";final static String params = "{\"token\":\"12345\","+ "\"appId\":\"20180628173051169c85d965d164ed9ab1281d22ff350ec19\","+ "\"appName\":\"test33\","+ "\"classTopic\":\"112\","+ "\"eventTag\":\"22\""+ "}";
public static void main(String[] args) {
String res = post(url, params);System.out.println(res);
}
/** * 发送HttpPost请求 *  * @param strURL *            服务地址 * @param params *            json字符串,例如: "{ \"id\":\"12345\" }" ;其中属性名必须带双引号<br/> * @return 成功:返回json字符串<br/> */public static String post(String strURL, String params) {System.out.println(strURL);System.out.println(params);BufferedReader reader = null;try {URL url = new URL(strURL);// 创建连接HttpURLConnection connection = (HttpURLConnection) url.openConnection();connection.setDoOutput(true);connection.setDoInput(true);connection.setUseCaches(false);connection.setInstanceFollowRedirects(true);connection.setRequestMethod("POST"); // 设置请求方式// connection.setRequestProperty("Accept", "application/json"); // 设置接收数据的格式connection.setRequestProperty("Content-Type", "application/json"); // 设置发送数据的格式connection.connect();OutputStreamWriter out = new OutputStreamWriter(connection.getOutputStream(), "UTF-8"); // utf-8编码out.append(params);out.flush();out.close();// 读取响应reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), "UTF-8"));String line;String res = "";while ((line = reader.readLine()) != null) {res += line;}reader.close();
return res;} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}return "error"; // 自定义错误信息}
}