Java 从服务器下载文件到本地

运行main方法即可运行。。。

package com.Manage.control;

import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

public class aatest {
	public static boolean saveUrlAs(String photoUrl, String fileName) {
		//此方法只能用户HTTP协议
		    try {
		      URL url = new URL(photoUrl);
		      HttpURLConnection connection = (HttpURLConnection) url.openConnection();
		      DataInputStream in = new DataInputStream(connection.getInputStream());
		      DataOutputStream out = new DataOutputStream(new FileOutputStream(fileName));
		      byte[] buffer = new byte[4096];
		      int count = 0;
		      while ((count = in.read(buffer)) > 0) {
		        out.write(buffer, 0, count);
		      }
		      out.close();
		      in.close();
		      return true;
		    }
		    catch (Exception e) {
		      return false;
		    }
		  }
		 
		public String getDocumentAt(String urlString) {
		//此方法兼容HTTP和FTP协议
		    StringBuffer document = new StringBuffer();
		    try {
		      URL url = new URL(urlString);
		      URLConnection conn = url.openConnection();
		      BufferedReader reader = new BufferedReader(new InputStreamReader(conn.
		          getInputStream()));
		      String line = null;
		      while ( (line = reader.readLine()) != null) {
		        document.append(line + "/n");
		      }
		      reader.close();
		    }
		    catch (MalformedURLException e) {
		      System.out.println("Unable to connect to URL: " + urlString);
		    }
		    catch (IOException e) {
		      System.out.println("IOException when connecting to URL: " + urlString);
		    }
		    return document.toString();
		  }
		
		public static void main(String[] args) {
		 
			
			  String photoUrl = "https://ss0.bdstatic.com/5aV1bjqh_Q23odCf/static/superman/img/logo/bd_logo1_31bdc765.png";			  			 			 
			  String fileName = photoUrl.substring(photoUrl.lastIndexOf("/"));
			  String filePath = "d:/";
			  boolean flag = saveUrlAs(photoUrl, filePath + fileName);
			  System.out.println("Run ok!/n
Get URL file " + flag);
			  
		}
}