how to replace a string/word in a text file in groovy

Question

Hello I am using groovy 2.1.5 and I have to write a code which show the contens/files of a directory with a given path then it makes a backup of the file and replace a word/string from the file. here is the code I have used to try to replace a word in the file selected

String contents = new File( '/geretd/resume.txt' ).getText( 'UTF-8' )  contents = contents.replaceAll( 'visa', 'viva' ) 

also here is my complete code if anyone would like to modify it in a more efficient way, I will appreciate it since I am learning.

def dir = new File('/geretd') dir.eachFile {      if (it.isFile()) {         println it.canonicalPath     } }  copy = { File src,File dest->       def input = src.newDataInputStream()     def output = dest.newDataOutputStream()      output << input       input.close()     output.close() }  //File srcFile  = new File(args[0]) //File destFile = new File(args[1])  File srcFile  = new File('/geretd/resume.txt') File destFile = new File('/geretd/resumebak.txt') copy(srcFile,destFile)  x = " " println x  def dire = new File('/geretd') dir.eachFile {      if (it.isFile()) {         println it.canonicalPath     } }  String contents = new File( '/geretd/resume.txt' ).getText( 'UTF-8' )  contents = contents.replaceAll( 'visa', 'viva' ) 

Answer 1

As an alternative to loading the whole file into memory, you could do each line in turn

new File( 'destination.txt' ).withWriter { w ->   new File( 'source.txt' ).eachLine { line ->     w << line.replaceAll( 'World', 'World!!!' ) + System.getProperty("line.separator")   } } 

Of course this (and dmahapatro's answer) rely on the words you are replacing not spanning across lines