JAVA project on Encryption and Decryption of Message This is a Netbeans Project. by Devansh Koolwal

1. W E M A D E I T !
Akhil Yadav - ENG18CA0008
Devansh Koolwal - ENG18CA0014
BCA-2nd
JAVA PROJECT
Encryption Decryption
Dayananda Sagar University

2. T h r a s h . j a v a
package encryption.java;
public class thrash {
char[] alpha="ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
int[][] alphai={
{42,43,75,76,24,85,68,80,79,82,55,61,26,56,91,28,89,92,19,23,88,87,96,14,52,58},
{81,21,38,72,55,56,69,25,30,88,82,24,34,10,57,79,77,94,18,76,20,98,16,66,40,95},
{31,89,23,17,81,25,63,60,93,75,32,77,19,41,66,20,45,47,65,33,99,29,52,72,76,80},
{10,79,54,59,18,32,38,16,12,71,99,85,34,36,31,17,87,82,94,88,46,93,89,51,13,44},
{29,70,49,52,10,65,44,64,35,39,96,55,17,26,98,75,11,16,21,19,31,15,71,69,81,30},
{87,18,54,62,57,60,83,76,44,91,84,16,69,97,93,51,58,94,98,59,15,61,42,65,81,70},
{31,45,67,79,63,35,53,42,32,77,51,27,90,70,78,14,84,73,37,10,54,95,62,81,22,66}
};
//alphai represents 7 sets of character in numeric form
int [][] numri={
{42,43,75,76,24,85,68,80,79,82},
{81,21,38,72,55,56,69,25,30,88},
{31,89,23,17,81,25,63,60,93,75},
{10,79,54,59,16,31,38,16,12,71},
{29,70,39,52,10,65,64,64,35,39},
{87,18,58,60,51,60,83,76,44,92},
{34,45,67,79,63,37,53,42,34,77},
{78,37,77,12,91,91,36,87,15,52}};
//numri represents 7 sets of Numbers

3. char [][] stringcase={{'a','c','n','l','o'},{'y','u','r','d','q',},{'s','i','z','w','x'},{'b','e','f','h','j'}};
//stringcase[0][_] - lowercase
//stringcase[1][_] - Uppercase
//stringcase[2][_] - space
//stringcase[3][_] - number
char[] sett={'@','!','"',']','+','%','#'};
//sett represents set index
}

4. M e s s a g e _ E n c r y p t I o n . j a v a
package encryption;
import javax.swing.JFrame;
import java.util.Random;
import javax.swing.JOptionPane;
public class Message_Encryption extends javax.swing.JFrame{
private void formWindowOpened(java.awt.event.WindowEvent evt) {
this.setExtendedState(JFrame.MAXIMIZED_BOTH);
this.setVisible(true);
jLabel1.setHorizontalAlignment(jLabel1.CENTER);
}
private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
System.exit(0);
}
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
thrash th=new thrash();
String pre;
Random random=new Random();
String in=jTextPane2.getText();
char [] input=in.toCharArray();
for(int i=0;i<input.length;i++){
char temp=input[i];

5. //for string
if( (temp>='a' && temp<='z') || (temp>='A' && temp<='Z')){
if(temp>='a' && temp<='z'){
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+th.stringcase[0][(random.nextInt(4))]);
temp=Character.toUpperCase(temp);
}
else if(temp>='A' && temp<='Z'){
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+th.stringcase[1][(random.nextInt(4))]);
}
int sum=0;
int set=random.nextInt(6);
for(int j=0;j<26;j++){
if(temp==th.alpha[j]){
sum=th.alphai[(set)][j];
}}
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+th.sett[(set)]);
for(int j=0;j<5;j++){
int c=random.nextInt(9);
sum=sum-c;
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+c);
}

6. if((sum>9 && sum<99) || (sum<-9 && sum>-99)){
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"y");
}
else{
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"z");
}
if(sum<0){
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"m"+(-(sum)));
}
else {
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"n"+sum);
}
}
//for space
else if(temp==' '){
int sum=random.nextInt(99);
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+(th.stringcase[2][random.nextInt(5)]));
pre=jTextPane1.getText();
jTextPane1.setText(pre+""+(th.sett[(random.nextInt(6))]));
for(int j=0;j<5;j++){
int c=random.nextInt(9);

7. sum=sum-c;
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+c);
}
if((sum>9 && sum<99) || (sum<-9 && sum>-99)){
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"y");
}
else{
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"z");
}
if(sum<0){
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"m"+(-(sum)));
}
else {
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"n"+sum);
}
}
//for numbers
else if(temp>='0' && temp<='9'){
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+(th.stringcase[3][random.nextInt(5)]));
int sum=0;

8. int set=random.nextInt(6);
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+th.sett[(set)]);
for(int j=0;j<=9;j++){
sum=th.numri[(set)][(Character.getNumericValue(temp))];
}
for(int j=0;j<5;j++){
int c=random.nextInt(9);
sum=sum-c;
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+c);
}
if((sum>9 && sum<99) || (sum<-9 && sum>-99)){
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"y");
}
else{
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"z");
}
if(sum<0){
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"m"+(-(sum)));

9. }
else {
pre=jTextPane1.getText();
jTextPane1.setText(""+pre+""+"n"+sum);
}
}
}
}
private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {
jTextPane1.setText("");
}

10. ME S S A G E _ d e c r y p t I o n . j a v a
package encryption;
import javax.swing.JFrame;
import java.util.Random;
import javax.swing.JOptionPane;
public class Message_Decryption extends javax.swing.JFrame{
private void formWindowOpened(java.awt.event.WindowEvent evt) {
this.setExtendedState(JFrame.MAXIMIZED_BOTH);
this.setVisible(true);
jLabel1.setHorizontalAlignment(jLabel1.CENTER);
}
private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
System.exit(0);
}
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
thrash th=new thrash();
String pre;
String cod=jTextPane2.getText();
char[] code=cod.toCharArray();
int stringcase=-1;
int set=-1;
for(int i=0;i<code.length;){
for(int j=i;j<(i+9);j++){
for(int k=0;k<4;k++){
for(int h=0;h<5;h++){
if(code[j]==th.stringcase[k][h]) {

11. stringcase=k;
}
}
}
j++;
for(int k=0;k<7;k++){
if(code[j]==th.sett[k]){
set=k;
}
}
j++;
//lower case
if(stringcase==0){
int ch=-1;
int sum=0;
for(int num_sum=j;num_sum<(j+5);num_sum++){
sum=sum+Character.getNumericValue(code[num_sum]);
}
j=j+5;
if(code[(j+1)]=='m'){
if(code[j]=='y'){
++i;
int a=Character.getNumericValue(code[j+2]);
int b=Character.getNumericValue(code[j+3]);

12. int c=(a*10)+b;
sum=sum-c;
}
else{
int a=Character.getNumericValue(code[j+2]);
sum=sum-a;
}
}
else if(code[(j+1)]=='n'){
if(code[j]=='y'){
++i;
int a=Character.getNumericValue(code[j+2]);
int b=Character.getNumericValue(code[j+3]);
int c=(a*10)+b;
sum=sum+c;
}
else{
int a=Character.getNumericValue(code[j+2]);
sum=sum+a;
}
}
for(int k=0;k<26;k++){
if(sum==th.alphai[set][k]){

13. ch=k;
}
}
pre=jTextPane1.getText();
jTextPane1.setText(pre+""+Character.toLowerCase(th.alpha[ch]) );
break;
}
//Upper case
else if(stringcase==1){
pre=jTextPane1.getText();//
int ch=-1;
int sum=0;
for(int num_sum=j;num_sum<(j+5);num_sum++){
sum=sum+Character.getNumericValue(code[num_sum]);
}
j=j+5;
if(code[(j+1)]=='m'){
if(code[j]=='y'){
++i;
int a=Character.getNumericValue(code[j+2]);
int b=Character.getNumericValue(code[j+3]);
int c=(a*10)+b;

14. sum=sum-c;
}
else{
int a=Character.getNumericValue(code[j+2]);
sum=sum-a;
}
}
else if(code[(j+1)]=='n'){
if(code[j]=='y'){
++i;
int a=Character.getNumericValue(code[j+2]);
int b=Character.getNumericValue(code[j+3]);
int c=(a*10)+b;
sum=sum+c;
}
else{
int a=Character.getNumericValue(code[j+2]);
sum=sum+a;
}
}
for(int k=0;k<26;k++){
if(sum==th.alphai[set][k]){
ch=k;
}

15. }
pre=jTextPane1.getText();
jTextPane1.setText(pre+""+Character.toUpperCase(th.alpha[ch]) );
break;
}
//space
else if(stringcase==2){
pre=jTextPane1.getText();
jTextPane1.setText(pre+""+" ");
if(code[(i+7)]=='y'){
i++;
}
break;
}
//number
else if(stringcase==3){
int ch=-1;
int sum=0;
for(int num_sum=j;num_sum<(j+5);num_sum++){
sum=sum+Character.getNumericValue(code[num_sum]);
}
j=j+5;

16. if(code[(j+1)]=='m'){
if(code[j]=='y'){
++i;
int a=Character.getNumericValue(code[j+2]);
int b=Character.getNumericValue(code[j+3]);
int c=(a*10)+b;
sum=sum-c;
}
else{
int a=Character.getNumericValue(code[j+2]);
sum=sum-a;
}
}
else if(code[(j+1)]=='n'){
if(code[j]=='y'){
++i;
int a=Character.getNumericValue(code[j+2]);
int b=Character.getNumericValue(code[j+3]);
int c=(a*10)+b;
sum=sum+c;
}
else{
int a=Character.getNumericValue(code[j+2]);

17. sum=sum+a;
}
}
for(int k=0;k<10;k++){
if(sum==th.numri[set][k]){
ch=k;
}
}
pre=jTextPane1.getText();
jTextPane1.setText(pre+""+ch);
break;}}
i+=10;}}
private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {
jTextPane1.setText("");
}

18. M a n u a l R e p r e s e n t a t I o n
• First it will check the case of char
1. Lower case = Print random character from stringcase of index [0][_]
2. Upper case = Print random character from stringcase of index [1][_]
3. Space = Print random character from stringcase of index [2][_]
4. Number = Print random character from stringcase of index [3][_]
• Then code will assign a random set of 0 to 7
• Print sign of set according to set index from sett[]
• Then it will select the index from alpha according to char
• Then using set and alpha index fetch sum from alphai or from numri
• Then code will divide sum into 6 parts and the sum of all 6 is equal to the no. fetched
by the code
• First 5 no. are under 9 and last no. can be between -99 to 99
• Then code will print first 5 numbers
• Then code will check condition of 6th
no.
1. If number is of 2 digit it will print “y” else “z”
2. If number is negative then code will print m else n
Example:
Algorithm Output
If char = ‘b’;
‘a’ is Lower case letter then code will print
any char from stringcase[0][_]
a
Random choose no 0-7 and print sett using chosen no.
as index
a!
Using Linear Search find out the index of char in alpha
From index and set fetch the value of sum from alphai
Random print 5 no. (0-9) a!58019
Then will find out the difference of sum of 5nos and the
sum fetched by the code from alphai
If no. is of 2 digit the print y else z a!58019z
If 6th
no. is negative then print m else n a!58019zm
If no. is negative then convert into positive and print a!58019zm2