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Thread: Basic Java Encryption

  1. #1
    Junior Member
    Join Date
    Apr 2010
    Thanked 1 Time in 1 Post

    Default Basic Java Encryption

    public static String encryptLine(char[] cipher, String line) {		
    	char[] alphabet ={'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p',
            	for (int j = 0; j < 26; j++) {
    		char b = alphabet[j];
    		char c = cipher[j];
    		String bString = Character.toString(b);
    		String cString = Character.toString(c); line = line.replace(bString, cString);  		
    	return line;

    String line is later outputted by a PrintStream. The portion that is wrong with my program is shown above. I am trying to encrypt lines of String in a text file. The above code doesn't work because once you replace a character from cipher[], it can later be changed again during the loop. Any ideas on how I should go about doing this?
    Last edited by BronxBomber; April 9th, 2010 at 06:40 AM.

  2. The Following User Says Thank You to BronxBomber For This Useful Post:

    rcook6 (May 3rd, 2012)

  3. #2
    Administrator copeg's Avatar
    Join Date
    Oct 2009
    Thanked 833 Times in 772 Posts
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    Default Re: Basic Java Encryption

    Iterate over the length of the string and not the size of the alphabet. For example
    for ( int i = 0; i < line.length(); i++ ){
        //replace character at position i in line with your encryption value

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