在java中,file.delete()
返回true
或false
File file
是否指向不存在的文件?
我意识到这是一个基本问题,很容易通过测试,但我得到了奇怪的结果,并希望得到确认。
答案 0 :(得分:8)
来自 http://java.sun.com/j2se/1.5.0/docs/api/java/io/File.html#delete():
返回:当且仅当文件或目录被成功删除时才返回true;否则是假的
因此,对于不存在的文件,它应该返回false。以下测试证实了这一点:
import java.io.File;
public class FileTest
{
public static void main(String[] args)
{
File file = new File("non-existent file");
boolean result = file.delete();
System.out.println(result);
}
}
编译并运行此代码会产生错误。
答案 1 :(得分:4)
这不会导致FileNotFoundException吗?
编辑:
确实会导致错误:
import java.io.File;
public class FileDoesNotExistTest {
public static void main( String[] args ) {
final boolean result = new File( "test" ).delete();
System.out.println( "result: |" + result + "|" );
}
}
打印false
答案 2 :(得分:2)
官方javadoc:
Deletes the file or directory denoted by this abstract pathname. If this pathname denotes a directory, then the directory must be empty in order to be deleted.
Returns:
true if and only if the file or directory is successfully deleted; false otherwise
Throws:
SecurityException - If a security manager exists and its SecurityManager.checkDelete(java.lang.String) method denies delete access to the file
所以,错误。