Converting string to int Java

Use Integer.valueOf()method to convert string to integer object.

/**
 * @author lautturi.com
 * Java example: Convert string to int in Java
 */

import java.util.*;

public class Lautturi {

	public static void main(String[] args) {

		String str = "123";
		Integer result = Integer.valueOf(str);
	    System.out.print(result);

	}
}

output:

123

If we try to convert a string which has no numbers,we will get the NumberFormatException:

import java.util.*;

public class Lautturi {

	public static void main(String[] args) {

		String str = "abcd";
		Integer result = Integer.valueOf(str);
	    System.out.print(result);

	}
}

output:

Exception in thread "main" java.lang.NumberFormatException: For input string: "abcd"
	at java.base/java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
	at java.base/java.lang.Integer.parseInt(Integer.java:652)
	at java.base/java.lang.Integer.valueOf(Integer.java:983)