question: public LockableFileWriter ( File file , Charset encoding , boolean append , String lockDir ) throws IOException { super ( ) ; file = file . getAbsoluteFile ( ) ; if ( file . getParentFile ( ) != null ) { FileUtils . forceMkdir ( file . getParentFile ( ) ) ; } if ( file . isDirectory ( ) ) { throw new IOException ( "File specified is a directory" ) ; } if ( lockDir == null ) { lockDir = System . getProperty ( "java.io.tmpdir" ) ; } File lockDirFile = new File ( lockDir ) ; FileUtils . forceMkdir ( lockDirFile ) ; testLockDir ( lockDirFile ) ; lockFile = new File ( lockDirFile , file . getName ( ) + LCK ) ; createLock ( ) ; out = initWriter ( file , encoding , append ) ; }
target:  Constructs a LockableFileWriter with a file encoding.