HttpUtils.java 网络下载工具类

Posted 2020-09-25

package Http;


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

/**
 * 网络下载工具类
 * 功能：下载字节数组，下载文本数据
 * 下载数字数组（文本 图片 mp3）
 * 下载文本数据
 * Created by lxj-pc on 2017/6/27.
 */
public class HttpUtils {
    public static byte[] get(String url) throws IOException {
        //网络下载
        HttpURLConnection conn = (HttpURLConnection) new URL
                (url).openConnection();

        InputStream is = conn.getInputStream();
        ByteArrayOutputStream baos = null;

        if (conn.getResponseCode() == 200) {
            baos = new ByteArrayOutputStream();
            byte[] buffer = new byte[8 * 1024];//8k
            int len = -1;

            //获取资源的总长度
            int totalLen = conn.getContentLength();
            int curLen = 0;
            while ((len = is.read(buffer)) != -1) {

                baos.write(buffer, 0, len);
                //3.计算下载 进度
                curLen += len;
                int p = curLen * 100 / totalLen;
                System.out.println("jindu" + p + "%");

            }

            is.close();
            conn.disconnect();

        }

        return baos.toByteArray();
    }

    public static String getText(String url) throws Exception{


            return new String(get(url), "utf-8");

    }

}