How add a data to char array from char variable in Java programming [closed]

Question

I am going to make a password generator. But I cannot a char variable into a char array can you help me? I tried with charAt() but it didn't work well. Now, what should I do?

import java.util.concurrent.ThreadLocalRandom;
public class GenerateRandomString {

    /**
     * @param args The command-line arguments
     */
    public static void RandomMaker(){
        String text = "ABCDEFGHIKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890";
        int min_val = 1;
        int max_val = 61;
        char[] pass = {'1'};
        char test = 'x';
        ThreadLocalRandom tlr = ThreadLocalRandom.current();
        for (int i = 0; i<19; i++){
            int randomNum = tlr.nextInt(min_val, max_val);
            String x = text.substring(randomNum-1, randomNum);
            for(short z = 0; z < 1; z++){
                test = x.charAt(0);
            }
            //char test = x.charAt(0);
            //pass[i] = x.charAt(0);
            System.out.println(test);
            System.err.println(x);
            pass[i] = test;
        }
        System.out.println("\n"+pass.length);
    }
    public static void main(String[] args) {
        // TODO code application logic here
        GenerateRandomString obj = new GenerateRandomString();
        GenerateRandomString.RandomMaker();
        System.out.println("Successful");
    }
    
}

Answer 1

You are creating a char[] pass variable with size 1. This is why it throws an java.lang.ArrayIndexOutOfBoundsException.

You should initialize with the size you want to use (19). You can try doing:

      char[] pass = new char[19];

Another option is define a List and add items dynamically.

I hope this help you.

Answer 2

If you want to convert text to Character array:

String str = "putyourtexthere";
  
        // Creating array of string length
        char[] ch = new char[str.length()];
  
        // Copy character by character into array
        for (int i = 0; i < str.length(); i++) {
            ch[i] = str.charAt(i);
        }
  
        // Printing content of array
        for (char c : ch) {
            System.out.println(c);
        }

Answer 3

I did it in this way Thanks all (?)

import java.util.*;
public class Random2 {

    /**
     * @param args the command line arguments
     */
    public static String text = "ABCDEFGHIKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890!@#$%^&*:;,<.>/?'|`";
    public static char[] pass = new char[85];
    public static int passlength = 0;
    public static int x = 0;
    public static String y = "1";

    public static void generator(){
        Random random = new Random();
        for (short t= 1; t <= passlength; t++){
            x = random.nextInt(text.length());
            y = text.substring(x, x+1);
            pass[t] = y.charAt(0);
            System.out.print(pass[t]);
        }
    }
    public static void main(String[] args) {
        // TODO code application logic here
        Random2 myclass = new Random2();
        Scanner scan = new Scanner(System.in);
        passlength = scan.nextInt();
        myclass.generator();
        //System.out.println(pass.length);
        System.out.println("\nSuccesfully");
    }
    
}