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从网上下载二进制文件存入本地磁盘中

2003-11-14 9:48:53

Java 实现这个功能非常简单，就是建立一个URL 然后进行操作就可以了。

以下是简单的程序代码，没有要求从控制太输入url。
[code]import java.net.*;
import java.io.*;
/**
从网上下载二进制文件存到本地
FileName:BinarySaver.java
@Author:Alec Cheung
MSN:eboysit@hotmail.com
Date:2003-5-21
Home:http://cheung.cxc.cc
http://www.andyfans.com
http://97741.126.com
Oicq:1695925
*/

public class BinarySaver {

public static void main(String args[]){

try{
URL root = new URL("http://localhost:8888/97741/images/title.jpg");
saveBinaryFile(root);
}

catch(IOException e){
System.err.println(e);
}

} //end main

public static void saveBinaryFile(URL u) throws IOException{
URLConnection uc = u.openConnection();
String contentType = uc.getContentType();
int contentLength = uc.getContentLength();

if (contentType.startsWith("text/") || (contentLength == -1))
{
throw new IOException("this is not a binary file.");
}

InputStream raw = uc.getInputStream();
InputStream in = new BufferedInputStream(raw);
byte[] data = new byte[contentLength];
int bytesRead = 0;
int offset = 0;
while (offset < contentLength)
{
bytesRead = in.read(data,offset,data.length-offset);
if(bytesRead == -1) break;
offset +=bytesRead;
}
in.close();

if (offset != contentLength)
{
throw new IOException("Only read "+offset+" bytes;Expected "+contentLength+" bytes.");
}

String fileName = u.getFile();
String filePath = "D:\\java\\";
fileName = fileName.substring(fileName.lastIndexOf('/')+1);
FileOutputStream fout = new FileOutputStream(filePath+fileName);
fout.write(data);
fout.flush();
fout.close();
}
}[/code]