CIS 3020 Project 5 - Revision history

Jka: /* Code */

2007-11-05T17:51:57Z

Code

Jka at 17:51, 5 November 2007

2007-11-05T17:51:11Z

Jka at 17:50, 5 November 2007

2007-11-05T17:50:53Z

New page

==Code==
===Cipher.java===
import java.lang.String;

public class Cipher {

//output string that holds encrypted message
private String output = new String();
//replacement letter for encryption (changes often!)
private String replacement = new String();
//how to know when to stop trying to replace letters
private int keyLen = 0;

private void clearOutput(){
//clear this.output
this.output = "";
}

public String getOutput(){
//return output
return(this.output);
}

public String encipher (String encode, String key, String message){
//reset this.output
clearOutput();
//determine key length
this.keyLen = (key.length()-1);
//return the encoded message
return(encode(encode, key, message));
}

private String encode(String encode, String key, String message) {
//is there anything left to encode?
if (message.length() != 0) {
// Get the first character in the initiator string.
//the following two lines (3 lines if you really want to,
//but letterReplacement would have to return this.replacement)
//could have been combined but weren't for clarity.
String letter = message.substring(0, 1);
//replace letter with encrypted letter
letterReplacement(letter, encode, key, 0);
//concatenate output with encoded letter
this.output = this.output.concat(this.replacement);
//repeat for next letter
encode(encode, key, message.substring(1));
} //end if
//end big if (length != 0)
return (this.output);
}//end next generation

private void letterReplacement(String letter, String encode, String key, int n){

//don't go out of bounds!
if (n<=this.keyLen){
//try to replace letter with encoded character
this.replacement = letter.replace(encode.charAt(n),key.charAt(n));
//did replacement succeed?
if (this.replacement.equals(letter)){
//if not, try again
letterReplacement(letter, encode, key, n+1);
}
}
}
}

@@ Line 66: / Line 66: @@
+   }
+}
+}
 </pre>

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 ==Code==
 ===Cipher.java===
 import java.lang.String;
@@ Line 66: / Line 67: @@
+}
+}