Question

I have written a code for random password generation.There are a string from where i have to make the password.so i try to categorize the string according to uppercase array , lower case array and digit array. but here comes a problem when..

         for(int k=0;k<Length;k++){
        if(asc[k]>=65 && asc[k]<=90){
            UpperCase[k]=(char)asc[k];
        }
        else if(asc[k]>=48 && asc[k]<=57){
            Digit[k]=(char)asc[k];
        }
        else {
            Mixed[k]=(char)asc[k];
        }
    } 

is executed it counts some space which i don’t want.coding looks like ugly sry for my poor coding.i know there is a lot more way to solve it but i want to go through this.here is my code. here is my code

import java.util.Random;

   public class Randompassgeneration
   {

final int MAX_LENGTH = 20;
final int MIN_LENGTH = 3;

char[] password=new char[25];
int [] asc=new int[18];
char[] UpperCase=new char[25];
char[] Digit=new char[25];
char[] Mixed=new char[25];
public void generate(String allowedCharacters)
{
    int Length=allowedCharacters.length();


    for (int i=0;i<Length;i++)
    {
        asc[i]=(int)allowedCharacters.charAt(i);

    }
    for (int k=0;k<Length;k++)
    {
        if (asc[k]>=65 && asc[k]<=90)
        {
            UpperCase[k]=(char)asc[k];
        }
        else if (asc[k]>=48 && asc[k]<=57)
        {
            Digit[k]=(char)asc[k];
        }
        else
        {
            Mixed[k]=(char)asc[k];
        }
    }

    String rp=null;
    StringBuilder Strbld=new StringBuilder();
    Random rnd=new Random();
    int ranStrLen=rnd.nextInt(MAX_LENGTH - MIN_LENGTH + 1) + MIN_LENGTH;
    Strbld.append(UpperCase[rnd.nextInt(UpperCase.length)]);
    Strbld.append(Digit[rnd.nextInt(Digit.length)]);

    for (int m=0; m<ranStrLen-2; m++)
    {
        Strbld.append(Mixed[rnd.nextInt(Mixed.length)]);

    }

    System.out.print(ranStrLen +"->"+ Strbld.toString());


}

public static void main(String[] args)
{
    String allowedCharacters = "weakPasSWorD1234$*";
    Randompassgeneration t=new Randompassgeneration();
    t.generate(allowedCharacters);
}
}

Any kind of suggestion?

Answer 1

“is executed it counts some space which i don’t want”

The white space is beacuse of your For loop

You were using the variable k for all the arrays,which resulted into the incremented value of k each time.So,this was making “gaps” between your arrays.

Change it to:

int point1=0,point2=0,point3=0;
for (int k=0;k<Length;k++)
{
    if (asc[k]>=65 && asc[k]<=90)
    {
        UpperCase[point1]=(char)asc[k];point1++;
        continue;
    }
    else if (asc[k]>=48 && asc[k]<=57)
    {
        Digit[point2]=(char)asc[k];point2++;
        continue;
    }
    else
    {
        Mixed[point3]=(char)asc[k];point3++;
    }

}
System.out.println(UpperCase);
System.out.println(Digit);
System.out.println(Mixed);

OutPut:

PSWD
1234
weakasor$*