在Java编程中,如何检查文件是否在服务器上被修改了?
以下示例显示如何检查文件是否在服务器上进行了修改。
package com.yiibai;
import java.net.URL; import java.net.URLConnection; public class FileModificationTime2 { public static void main(String[] argv) throws Exception { URL u = new URL("http://www.yiibai.com/static.v4/img/logo.png"); URLConnection uc = u.openConnection(); uc.setUseCaches(false); long timestamp = uc.getLastModified(); System.out.println("The last modification time of logo.png is :" + timestamp); } }
上述代码示例将产生以下结果 -
The last modification time of logo.png is :1481341017000
示例-2
以下是检查文件在服务器上修改的示例。
package com.yiibai;
import java.net.URL; import java.net.URLConnection; public class FileModificationTime { public static void main(String[] argv)throws Exception { URL u = new URL("http://www.yiibai.com/favicon.ico"); URLConnection uc = u.openConnection(); uc.setUseCaches(false); long timestamp = uc.getLastModified(); System.out.println("The last modification time of file is :"+timestamp); } }
上述代码示例将产生以下结果 -
The last modification time of file is :1367414578000