java 获取url 源码

package com.example.juliciy.myhttpclientproject_187241452;


import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;

public class HtmlService {

    public static String getHtml(String path) throws Exception {
        // 通过网络地址创建URL对象
        URL url = new URL(path);
        // 根据URL
        // 打开连接，URL.openConnection函数会根据URL的类型，返回不同的URLConnection子类的对象，这里URL是一个http，因此实际返回的是HttpURLConnection
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        // 设定URL的请求类别，有POST、GET 两类
        conn.setRequestMethod("GET");
        //设置从主机读取数据超时（单位：毫秒）
        conn.setConnectTimeout(5000);
        //设置连接主机超时（单位：毫秒）
        conn.setReadTimeout(5000);
        // 通过打开的连接读取的输入流,获取html数据
        InputStream inStream = conn.getInputStream();
        // 得到html的二进制数据
        byte[] data = readInputStream(inStream);
        // 是用指定的字符集解码指定的字节数组构造一个新的字符串
        String html = new String(data, "utf-8");
        return html;
    }

    /**
     * 读取输入流，得到html的二进制数据
     *
     * @param inStream
     * @return
     * @throws Exception
     */
    public static byte[] readInputStream(InputStream inStream) throws Exception {
        ByteArrayOutputStream outStream = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = 0;
        while ((len = inStream.read(buffer)) != -1) {
            outStream.write(buffer, 0, len);
        }
        inStream.close();
        return outStream.toByteArray();
    }

}




package com.example.juliciy.myhttpclientproject_187241452;

import android.app.Activity;
import android.os.StrictMode;
import android.os.Bundle;
import android.widget.TextView;
public class MainActivity extends Activity {

//    private String path = "https://blog.csdn.net/llixiangjian/article/details/72910557";
    private String path = "https://www.baidu.com/";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        if (android.os.Build.VERSION.SDK_INT > 9) {
            StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
            StrictMode.setThreadPolicy(policy);
        }


            TextView textView = (TextView)this.findViewById(R.id.textView);
        try {
            String htmlContent = HtmlService.getHtml(path);
            textView.setText(htmlContent);
        } catch (Exception e) {
            textView.setText("程序出现异常："+e.toString());
        }
    }
}