How to validate an empty textField that can accepts only integers?

Question

I wrote like this; but it fails to integer only textfields

if(textField_1.getText().length()==0)  

JOptionPane.showMessageDialog(null, "enter text in textfield");  

Please help...

Solution 1

Typically, when you are validating user input in Java, you will want to check for both null and empty string values. To check String objects for equality, you must use the .equals() method (not the == operator). Thus, a check for an empty String value might look something like this:

if ( val == null || val.trim().equals( "" ) )
{
    // handle empty String case
}
else
{
    // handle non-empty String case
}

Hope this helps

Solution 2

if(textField_1.getText().isEmpty()){
    JOptionPane.showMessageDialog(null, "enter text in textfield");  
}  

Comments

[Radu Murzea]

indeed, if you check Strings for equality, the equals method is the way to go. But the length method is very ok to check if a String is empty. Also, the getText method does not return null Strings.

[harry]

@user1213523 i am glad that i could help, you can accept my answer by clicking on right sign just below the vote mark.

[Muneeb Mirza]

I think u had no need to add description of urself. Thanks for an easy solution though. :)