这是通过HTTPURLConnection进行POST和GET的实现。

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;

public class PostGET {
    public static void main(String[] args) throws UnsupportedEncodingException {
        Map headerMap = new HashMap();
        String bodyStr = "{\"doc\":{\"status\":\"Disconnected\"}}";
        InputStream body = new ByteArrayInputStream(bodyStr.getBytes("UTF-8"));

        System.out.println("Sending POST");
        post("http://127.0.0.1:3000", headerMap, body);

        System.out.println("");

        System.out.println("Sending GET");
        get("http://127.0.0.1:3000?test=hello", headerMap);
    }

    public static void post(String targetUrl, Map headerMap,
            InputStream body) {
        HttpURLConnection http = null;
        try {
            http = (HttpURLConnection) new URL(targetUrl).openConnection();
            http.setRequestMethod("POST");
            http.setDoOutput(true);
            for (Map.Entry header : headerMap.entrySet()) {
                http.setRequestProperty(header.getKey(), header.getValue());
            }

            OutputStream out = http.getOutputStream();
            out.write(readInput(body));
            out.close();

            InputStream in = http.getInputStream();
            String response = new String(readInput(in), "UTF-8");

            System.out.println("Response code: " + http.getResponseCode());
            System.out.println("Response headers : " + http.getHeaderFields());
            System.out.println("response from server: " + response);


        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    public static void get(String targetUrl, Map headerMap) {
        HttpURLConnection http = null;
        try {
            http = (HttpURLConnection) new URL(targetUrl).openConnection();
            http.setRequestMethod("GET");

            for (Map.Entry header : headerMap.entrySet()) {
                http.setRequestProperty(header.getKey(), header.getValue());
            }

            InputStream in = http.getInputStream();
            String response = new String(readInput(in), "UTF-8");

            System.out.println("Response code: " + http.getResponseCode());
            System.out.println("Response headers : " + http.getHeaderFields());
            System.out.println("response from server: " + response);


        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    public static byte[] readInput(InputStream in) {
        ByteArrayOutputStream bais = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int readLen = -1;
        try {
            while ((readLen = in.read(buffer)) != -1) {
                bais.write(buffer, 0, readLen);
            }
            in.close();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return bais.toByteArray();
    }
}

下面是一个Nodejs服务器，可以通过以下方式对此进行测试

http = require('http');
server = http.createServer( function(req, res) {
    if (req.method == 'POST') {
        console.log("POST");
        var body = '';
        req.on('data', function (data) {
            body += data;
            console.log("Partial body: " + body);
        });
        req.on('end', function () {
            console.log("Body: " + body);
        });
        res.writeHead(200, {'Content-Type': 'text/html'});
        res.end('post received');
    } else if(req.method === 'GET') {
        console.log("GET");
        var params = req.url.split('?');
        params = params.length > 1 ?  params[1] : "";
        console.log('params : ' + params);

        var html = '
' + params+ '
';
        res.writeHead(200, {'Content-Type': 'text/html'});
        res.end(html);
    }

});

port = 3000;
host = '127.0.0.1';
server.listen(port, host);
console.log('Listening at http://' + host + ':' + port);

Java客户端输出

Sending POST
Response code: 200
Response headers : {Transfer-Encoding=[chunked], null=[HTTP/1.1 200 OK], Connection=[keep-alive], Date=[Thu, 31 Dec 2015 19:40:05 GMT], Content-Type=[text/html]}
response from server: post received

Sending GET
Response code: 200
Response headers : {Transfer-Encoding=[chunked], null=[HTTP/1.1 200 OK], Connection=[keep-alive], Date=[Thu, 31 Dec 2015 19:40:05 GMT], Content-Type=[text/html]}
response from server: 
test=hello

节点服务器输出

Listening at http://127.0.0.1:3000
POST
Partial body: {"doc":{"status":"Disconnected"}}
Body: {"doc":{"status":"Disconnected"}}
GET
params : test=hello