Java：HttpURLConnection发送GET和POST请求

package demo;
import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
public class HttpDemo {
    public static void main(String[] args) throws IOException {
        String url = "https://www.baidu.com/";
        // 得到connection对象
        URL httpUrl = new URL(url);
        HttpURLConnection connection = (HttpURLConnection) httpUrl.openConnection();
        //连接
        connection.connect();
        // 获取状态码 响应结果
        if (connection.getResponseCode() == HttpURLConnection.HTTP_OK) {
            InputStream inputStream = connection.getInputStream();
            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
            String line = null;
            StringBuffer buffer = new StringBuffer();
            while ((line = reader.readLine()) != null) {
                buffer.append(line);
            }
            reader.close();
            System.out.println(buffer.toString());
        }
        // 断开连接
        connection.disconnect();
    }
}

package demo;
import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
public class HttpDemo {
    public static void main(String[] args) throws IOException {
        String url = "http://httpbin.org/post";
        //得到connection对象
        URL httpUrl = new URL(url);
        HttpURLConnection connection = (HttpURLConnection) httpUrl.openConnection();
        //设置请求方式
        connection.setRequestMethod("POST");
        connection.setDoOutput(true);
        // 设置请求头
        connection.setRequestProperty("Accept", "*/*");
        // 设置请求体
        String body = "name=Tom&age=23";
        OutputStream outputStream = connection.getOutputStream();
        BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
        writer.write(body);
        writer.close();
        //连接
        connection.connect();
        // 获取状态码 响应结果
        if (connection.getResponseCode() == HttpURLConnection.HTTP_OK) {
            InputStream inputStream = connection.getInputStream();
            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
            String line = null;
            StringBuffer buffer = new StringBuffer();
            while ((line = reader.readLine()) != null) {
                buffer.append(line);
            }
            reader.close();
            System.out.println(buffer.toString());
        }
        // 断开连接
        connection.disconnect();
    }
}