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Write a Java Program to Create random strings
PROGRAM: Java Program to Create random strings
/*Java Program to Create random strings*/
1: Java program to generate a random string
import java.util.Random;
class Main {
public static void main(String[] args) {
// create a string of all characters
String alphabet = “ABCDEFGHIJKLMNOPQRSTUVWXYZ”;
// create random string builder
StringBuilder sb = new StringBuilder();
// create an object of Random class
Random random = new Random();
// specify length of random string
int length = 7;
for(int i = 0; i < length; i++) {
// generate random index number
int index = random.nextInt(alphabet.length());
// get character specified by index
// from the string
char randomChar = alphabet.charAt(index);
// append the character to string builder
sb.append(randomChar);
}
String randomString = sb.toString();
System.out.println(“Random String is: ” + randomString);
}
}
2: Java Program to generate a random alphanumeric string
import java.util.Random;
class Main {
public static void main(String[] args) {
// create a string of uppercase and lowercase characters and numbers
String upperAlphabet = “ABCDEFGHIJKLMNOPQRSTUVWXYZ”;
String lowerAlphabet = “abcdefghijklmnopqrstuvwxyz”;
String numbers = “0123456789”;
// combine all strings
String alphaNumeric = upperAlphabet + lowerAlphabet + numbers;
// create random string builder
StringBuilder sb = new StringBuilder();
// create an object of Random class
Random random = new Random();
// specify length of random string
int length = 10;
for(int i = 0; i < length; i++) {
// generate random index number
int index = random.nextInt(alphaNumeric.length());
// get character specified by index
// from the string
char randomChar = alphaNumeric.charAt(index);
// append the character to string builder
sb.append(randomChar);
}
String randomString = sb.toString();
System.out.println(“Random String is: ” + randomString);
}
}