random class in java for string code example

Example 1: generate random string in java

import java.util.Random;

public class Generator {
	public static String generateRandomPassword(int len) {
		String chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijk"
          +"lmnopqrstuvwxyz!@#$%&";
		Random rnd = new Random();
		StringBuilder sb = new StringBuilder(len);
		for (int i = 0; i < len; i++)
			sb.append(chars.charAt(rnd.nextInt(chars.length())));
		return sb.toString();
	}
}

Example 2: java random between two strings

import java.util.Random;
public class RandomSelect {

    public static void main (String [] args) {

         String [] arr = {"A", "B", "C", "D"};
         Random random = new Random();

         // randomly selects an index from the arr
         int select = random.nextInt(arr.length); 

         // prints out the value at the randomly selected index
         System.out.println("Random String selected: " + arr[select]); 
    }
}

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Java Example