Java根据web网站Url下载图片

 

 

package com.ronniewang.downloadpicture;

import java.io.DataInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;

import com.mysql.jdbc.Connection;
import com.mysql.jdbc.Statement;
import com.ronniewang.utilities.JdbcUtil;

public class DownloadPicture {

    public static void main(String[] args) {
       测试下载图片：
       http://img.iitu.net/img_lt/58pic/12/50/47/10U58PICMxQ.jpg
       http://img.iitu.net/img_lt/58pic/12/50/47/02C58PIC5hd.jpg
       http://img.iitu.net/img_lt/58pic/12/50/46/92E58PICZM4.jpg
        DownloadPicture downloadPicture = new DownloadPicture();
        ArrayList<String> urlList = downloadPicture.readUrlList();
        downloadPicture.downloadPicture(urlList);
    }

    /**
     * 传入要下载的图片的url列表，将url所对应的图片下载到本地
     * @param urlList
     */
    private void downloadPicture(ArrayList<String> urlList) {
        URL url = null;
        int imageNumber = 0;

        for (String urlString : urlList) {
            try {
                url = new URL(urlString);
                DataInputStream dataInputStream = new DataInputStream(url.openStream());
                String imageName = imageNumber + ".jpg";
                FileOutputStream fileOutputStream = new FileOutputStream(new File(imageName));

                byte[] buffer = new byte[1024];
                int length;

                while ((length = dataInputStream.read(buffer)) > 0) {
                    fileOutputStream.write(buffer, 0, length);
                }

                dataInputStream.close();
                fileOutputStream.close();
                imageNumber++;
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * 连接mysql数据库，通过查询数据库读取要下载的图片的url列表
     * @return
     */
    private ArrayList<String> readUrlList() {
        ArrayList<String> urlList = new ArrayList<String>();
        try {
            Connection connection = (Connection) JdbcUtil.getConnection();
            Statement statement = (Statement) connection.createStatement();
            String sql = "select url from url"; //查询语句换位相应select语句
            ResultSet resultSet = statement.executeQuery(sql);

            while (resultSet.next()) {
                String url = resultSet.getString("url");
                urlList.add(url);
                System.out.println(url);
            }

            JdbcUtil.free(resultSet, statement, connection);
        } catch (SQLException e) {
            e.printStackTrace();
        }

        return urlList;
    }

}