需要下載兩個jar包：commons-httpclient和commons-codes

Demo:

import java.io.FileOutputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

public class QuickStart {

    public static void main(String[] args) throws Exception {
        DefaultHttpClient httpclient = new DefaultHttpClient();
        HttpGet httpGet = new HttpGet("http:/");

        HttpResponse response1 = httpclient.execute(httpGet);

        // The underlying HTTP connection is still held by the response object
        // to allow the response content to be streamed directly from the network socket.
        // In order to ensure correct deallocation of system resources
        // the user MUST either fully consume the response content  or abort request
        // execution by calling HttpGet#releaseConnection().

        try {
            System.out.println(response1.getStatusLine());
            HttpEntity entity1 = response1.getEntity();
           
            System.out.println(entity1.getContentLength());
           
            OutputStream os = new FileOutputStream("c:\\a.html");
            entity1.writeTo(os);
        
            // do something useful with the response body
            // and ensure it is fully consumed
            EntityUtils.consume(entity1);
        } finally {
            httpGet.releaseConnection();
        }

       
       
        HttpPost httpPost = new HttpPost("http://****");
        List <NameValuePair> nvps = new ArrayList <NameValuePair>();
        nvps.add(new BasicNameValuePair("username", "vip"));
        nvps.add(new BasicNameValuePair("password", "secret"));
        httpPost.setEntity(new UrlEncodedFormEntity(nvps));
        HttpResponse response2 = httpclient.execute(httpPost);

        try {
            System.out.println(response2.getStatusLine());
            HttpEntity entity2 = response2.getEntity();
           
            // do something useful with the response body
            // and ensure it is fully consumed
            EntityUtils.consume(entity2);
        } finally {
            httpPost.releaseConnection();
        }
    }

}
詳情請看下載jar包中的demo示例。