Java删除 正在使用,java无法删除另一个进程正在使用的文件

I have this code

import org.apache.commons.io.FileUtils;

try {

FileUtils.copyURLToFile(new URL(SHA1_LINK), new File("SHA1.txt"));

if(!sameSha1()) {

System.out.println("sha diferentes");

FileUtils.copyURLToFile(new URL(LINK), new File(PROG));

}

} catch (Exception e) {

System.out.println("Internet is off");

}

//delete SHA1 file

Files.deleteIfExists(Paths.get("SHA1.txt"));

and when I execute it it says

java.nio.file.FileSystemException

The process cannot access the file because it is being used by another process (in sun.nio.fs.WindowsException)

In the sameSha1() I have this:

String sha1Txt = new Scanner(new File("SHA1.txt")).useDelimiter("\\Z").next();

I want to delete the file 'SHA1.txt'. How can I do this?

解决方案

I guess with sameSha1 you open SHA1.txt to read it and you forget to close it.

EDIT:

From your comment you contain the following line in sameSha1:

String sha1Txt = new Scanner(new File("SHA1.txt")).useDelimiter("\\Z").next();

So you create a scanner instance but you don't explicitly close it. You should do something like that:

Scanner s = new Scanner(new File("SHA1.txt"));

try {

String sha1Txt = s.useDelimiter("\\Z").next();

...

return result;

}

finally {

s.close();

}

Or as @HuStmpHrrr suggests in Java 7:

try(Scanner s = new Scanner(new File("SHA1.txt"))) {

String sha1Txt = s.useDelimiter("\\Z").next();

...

return result;

}