question: public int compare ( File file1 , File file2 ) { long size1 = 0 ; if ( file1 . isDirectory ( ) ) { size1 = sumDirectoryContents && file1 . exists ( ) ? FileUtils . sizeOfDirectory ( file1 ) : 0 ; } else { size1 = file1 . length ( ) ; } long size2 = 0 ; if ( file2 . isDirectory ( ) ) { size2 = sumDirectoryContents && file2 . exists ( ) ? FileUtils . sizeOfDirectory ( file2 ) : 0 ; } else { size2 = file2 . length ( ) ; } long result = size1 - size2 ; if ( result < 0 ) { return - 1 ; } else if ( result > 0 ) { return 1 ; } else { return 0 ; } }
target:  Compare the length of two files.