Java - Cannot assign a value to final variable query. It is final String

Question

I have a problem with final string. It is a mysql database client. I want to change query with clicking JButton.

public void run() {
final String query;
(...)
start.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e)
    {
if(firstSel==null || selchose.getText().equals(selchose_str) || selbase.getText().equals(base_str)) {
            query = "Select * FROM EMP";
        }
(...)

The problem is with

query = "Select * FROM EMP";

It shows me

cannot assign a value to final variable query

How to solve the problem?

I asked [a question](http://stackoverflow.com/questions/3981924/how-to-retrieve-a-value-that-must-be-computed-on-another-thread) a while back that gets at this same issue, and may be informative to you. — Matt McHenry, Apr 15 '12 at 14:01

score 2 · Answer 1 · answered Apr 15 '12 at 13:34

2

Either make the query String a private class field or a variable local to the anonymous inner ActionListener class.

answered Apr 15 '12 at 13:34

Hovercraft Full Of Eels

283,665
25
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@Ganjira: ??? This is trivial. Just declare query as a variable of the class not a variable inside just the run method. Surely you know how to do this, right? – Hovercraft Full Of Eels Apr 15 '12 at 13:47
Well, i declared query outside of the run method, but it shows the same problem. :/ – Ganjira Apr 15 '12 at 13:49
Not outside the run method, but in the class, up at the top. It will fix it. – Hovercraft Full Of Eels Apr 15 '12 at 13:53

score 0 · Accepted Answer · answered Apr 15 '12 at 13:48

0

class YOurClassName{

private String query; //make here.....<<<<<<<<

public void run() {

(...)
start.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e)
    {
if(firstSel==null || selchose.getText().equals(selchose_str) || selbase.getText().equals(base_str)) {
            query = "Select * FROM EMP";
        }
(...)


}

answered Apr 15 '12 at 13:48

Samir Mangroliya

39,918
16
117
134

1

@Ganjira: you really couldn't figure this out? – Hovercraft Full Of Eels Apr 15 '12 at 14:10

Java - Cannot assign a value to final variable query. It is final String

2 Answers2