Monoalphabetic-Caesar-and-Playfair-Cipher-Encryption-and-Decryption

Monoalphabetic, Caesar and Playfair Cipher Encryption and Decryption in Java GUI

Methods of Monoalphabetic, Caesar and Playfair Cipher Encryption and Decryption

![alt tag] (http://s30.postimg.org/45jt4qr01/Screen_Shot_2016_04_03_at_1_27_36_AM.png)

         private static char MonoAlphabeticEncrypt(char a) {
        int pos = (int)a;
        pos = (pos % 91)- 65;
        a = key.charAt(pos);
        return a;
    }
private static char MonoAlphabeticdecrypt(char a) {
        int ascii = 0;
        for(int i=0;i< key.length(); i++){
            if(key.charAt(i) == a)
                ascii = i + 65;
        }
        return (char)ascii;
    }

![alt tag] (http://s22.postimg.org/6v1kl4y0x/Screen_Shot_2016_04_03_at_1_27_10_AM.png)

private static char Caesarencrypt(char a, int i, int f) {
    int ascii = (int)a;
    ascii = ((ascii + f ) % 90);
    if(ascii < 65){//adjustment for characters bigger than Z
        ascii = ascii + 65;
    }
        //moving using 3 characters
    a = (char) ascii;
    return a;
}
private static char Caesardecrypt(char a, int i, int f) {
    int ascii = (int)a;
    ascii = ((ascii - f ) % 90);
    if(ascii < 65){//adjustment for characters smaller than a
        ascii = ascii + 25;
    }          
    //moving using 3 characters
    a = (char) ascii;
    return a;
}

![alt tag] (http://s17.postimg.org/hyw9hd2y7/Screen_Shot_2016_04_03_at_1_27_55_AM.png)

    private static String PlayFairencrypt(char c1, char c2) {
    int[] posa = new int[2];
    int[] posb = new int[2];
    String frag = "";
    posa = search(c1);
    posb = search(c2);
    if(posa[0] == posb[0]){//same row
        c1 = keymatPlayfair[posa[0]][(posa[1]+1)%5];
        c2 = keymatPlayfair[posb[0]][(posb[1]+1)%5];
        frag = (""+c1+c2+"");
    }
    else if(posa[1] == posb[1]){ //same column
        c1 = keymatPlayfair[(posa[0]+1)%5][posa[1]];
        c2 = keymatPlayfair[(posb[0]+1)%5][posb[1]];
        frag = (""+c1+c2+"");
    }
    else{
        c1 = keymatPlayfair[posb[0]][posa[1]];
        c2 = keymatPlayfair[posa[0]][posb[1]];
        frag = (""+c1+c2+"");
    }
    return frag;
}
private static String PlayFairdecrypt(char c1, char c2) {
    int[] posa = new int[2];
    int[] posb = new int[2];
    String frag = "";
    posa = search(c1);
    posb = search(c2);
    if(posa[0] == posb[0]){//same row
        c1 = keymatPlayfair[posa[0]][(posa[1]-1)%5];
        c2 = keymatPlayfair[posb[0]][(posb[1]-1)%5];
        frag = (""+c1+c2+"");
    }
    else if(posa[1] == posb[1]){ //same column
        c1 = keymatPlayfair[(posa[0]-1)%5][posa[1]];
        c2 = keymatPlayfair[(posb[0]-1)%5][posb[1]];
        frag = (""+c1+c2+"");
    }
    else{
        c1 = keymatPlayfair[posb[0]][posa[1]];
        c2 = keymatPlayfair[posa[0]][posb[1]];
        frag = (""+c1+c2+"");
    }
    return frag;
}
private static int[] search(char c) {
    int i,j;
    int[] pos = new int[2];
    for (i = 0; i < 5; i++) {
        for (j = 0; j < 5; j++) {
            if (keymatPlayfair[i][j] == c){
                pos[0] = i;
                pos[1] = j;
                break;
            }
        }
    }
    return pos;
}

AhmedKaram2/Monoalphabetic-Caesar-and-Playfair-Cipher-Encryption-and-Decryption

Monoalphabetic-Caesar-and-Playfair-Cipher-Encryption-and-Decryption