What value is returned by empty JTextField?

[rdg2cig]

I would like check to see if the user entered any value in a JTextField before clicking a JButton in order determine the branch to take in a conditional statement. In the JButton actionPerformed() method I have a statement such as:

if(JTextField1.getText() == null){
... do something ...
}
else{
... do something else ...
}

My problem is that 'null' does not appear to be returned from an empty JTextField, nor is an empty String (i.e. "&quot. How can I determine the JTextField did not have anything entered into it when the button was clicked?

 

[pipk]

i think the empty string comparison should work. except that you will need to use the equals method in the comparison. e.g.

if(yourJTextField.getText().equals("&quot)

hope this helps

 

[pipk]

actually this should work with null as well, that is the value that is returned, its just that you have to remember that getText() returns a String object, so you must use the equals method.

if(yourJtextField.getText().equals(null))

should also work.

You only use the double equals on Strings == to check if the two String references are in fact pointing to the same object. (java, correct me if i am wrong anyone, mainly uses references rather than values blah blah blah)

 

[rdg2cig]

I tried the first solution,

if(jTextField1.getText().equals("&quot){
...
}

and it worked. The second solution,

if(jTextField1.getText().equals(null)){
...
}

did not work. I will use the first solution. Thanks for the help.

 

[kook04]

Or, you could check against the length of the string taken from the JTextField:

String s = textField.getText().trim();
if (s.length() = 0){

//JTextField is empty...

}

I usually use the trim( ) method just to be safe in case someone just presses the space bar a couple of times in the text field, it will eliminate all whitespace. ------
KJR

 

[pipk]

ok, i need to go and recheck the null thing, glad to be of service.