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Thread: Need help with replace function

  1. #1
    Junior Member
    Join Date
    Jan 2019
    Thanked 0 Times in 0 Posts

    Default Need help with replace function

    My code(pasted below) basically replaces A, B, C with C, P, Q.
    My new requirement is, I am going to create a file and then it has to replace the A, B, C of file content with C, P, Q. How do I do it?
    for example: let's say the name of the file is the filename.txt.So what changes do I have to make to existing code, please help

    public class replacefunction1 {
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
    		 File file = new File("filename.txt"); 
    	    HashMap<Character, Character> replacements = new HashMap<>();
    	    replacements.put('a', 'c');
    	    replacements.put('b', 'p');
    	    replacements.put('c', 'q');
    	    String input =  "abcd";
    	    StringBuilder output = new StringBuilder();
    	    for (Character c : input.toCharArray()) {
    	        output.append(replacements.getOrDefault(c, c));

  2. #2
    Super Moderator Norm's Avatar
    Join Date
    May 2010
    Eastern Florida
    Thanked 2,710 Times in 2,660 Posts

    Default Re: Need help with replace function

    Also posted at: https://www.dreamincode.net/forums/t...lace-function/
    If you don't understand my answer, don't ignore it, ask a question.

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