java.lang.NumberFormatException: while parsing String to Integer in Java

In this Example we are going to understand the exceptions while parsing the string to int .

Error Message :

Exception in thread "main" java.lang.NumberFormatException: For input string: ""

       at java.base/java.lang.NumberFormatException.forInputString(NumberFormatException.java:68)

       at java.base/java.lang.Integer.parseInt(Integer.java:668)

       at java.base/java.lang.Integer.parseInt(Integer.java:776)

       at com.src.ArrayDititsSum.convertInt2Array(ArrayDititsSum.java:26)

       at com.src.ArrayDititsSum.main(ArrayDititsSum.java:12)

Error Description :

package com.src;

public class ArrayDititsSum {

       public static void main(String[] args) {

             

              convertArray(963);

       }

       public static void convertArray(int num)  {

           String str = Integer.toString(num);

           String temp;

           int temp1;

           int [] intArray = new int[str.length()];

           for(int i=0;i<=str.length();i++) {

               if (i!=str.length()) {

                   temp = str.substring(i, i+1);

               } else {

                   temp = str.substring(i);

               }

               temp1 =  Integer.parseInt(temp);   

               intArray[i] = temp1;

           }

                   }         

}

In the above example due to the yellow background color code we are getting the error of  red background color code.

While iterationthe iteration value starts from 0 and it will iterate more then the string length so the string value come as "" and the controller will go to else part and giving the NumberFormat Exception.

Solution:

We have simplified the code to avoid the exception. We should take care while giving the String input for parsing to Integer.

package com.src;

public class ArrayDititsSum {

       public static void main(String[] args) {

             

              convertArray(963);

       }

       public static void convertArray(int num)  {

           String str = Integer.toString(num);

           String temp;

           int temp1;

           int [] intArray = new int[str.length()];

           for(int i=0;i<str.length();i++) {

                   temp = str.substring(i, i+1);

               temp1 =  Integer.parseInt(temp);   

               intArray[i] = temp1;

              

           }

           System.out.println(intArray.length);             

       }

}

Output:

3