Re: How to implement Global variables in java which can be shared across several files ?

From:

aks_java <atindras@gmail.com>

Newsgroups:

comp.lang.java.programmer

Date:

Sat, 6 Jun 2009 21:23:36 -0700 (PDT)

Message-ID:

<d1b6f88d-693d-4013-82c2-a61d171c844e@q37g2000vbi.googlegroups.com>

I'm sorry, the code for ActionCalculator.java is:

/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package calculator;

/**
*
* @author Owner
*/
import java.awt.event.*;
import javax.swing.*;

public class ActionCalculator implements ActionListener {
    private Operations operations = new Operations ();
    public void actionPerformed(ActionEvent event) {
        String pressedButton = ((JButton) event.getSource()).getText
();

        if (pressedButton.equals("C")) {
            calculator.displayField.setText("0");
            calculator.operatorUsed = "=";
            calculator.prevValue = 0;
            calculator.resetFlag = false;
            return;
        }
        if (pressedButton.equals("CE")) {
            calculator.displayField.setText("0");
            calculator.resetFlag = false;
            return;
        }
        try {
            Double.parseDouble(calculator.displayField.getText());
        } catch (Exception e) {
            calculator.resetFlag = true;
            return;
        }
        for (int i = 0; i < 10; i++) {
            if (pressedButton.equals("" + i)) {
                if (calculator.resetFlag ||
calculator.displayField.getText().equals("0")) {
                    calculator.displayField.setText("");
                }
                calculator.displayField.setText
(calculator.displayField.getText() + i);
                calculator.resetFlag = false;
                return;
            }
        }
        if (pressedButton.equals("")) {
            return;
        }
        if (pressedButton.equals("MR")) {
            if (!calculator.memRegVal.equals("")) {
                calculator.displayField.setText(calculator.memRegVal);
            }
            return;
        }
        if (pressedButton.equals("MS")) {
            calculator.memRegVal = calculator.displayField.getText();
            calculator.memRegLabel.setText("M");
            return;
        }
        if (pressedButton.equals("MC")) {
            calculator.memRegLabel.setText(calculator.memRegVal = "");
            return;
        }
        if (pressedButton.equals("M+")) {
            if (!calculator.memRegVal.equals("")) {
                calculator.memRegVal = "" + (Double.parseDouble
(calculator.memRegVal) + Double.parseDouble
(calculator.displayField.getText()));
            } else {
                calculator.memRegVal = calculator.displayField.getText
();
            }
            calculator.memRegLabel.setText("M");
            return;
        }
        if (pressedButton.equals("Backspace")) {
            String displayedText = calculator.displayField.getText();
            if (displayedText.length() > 0) {
                displayedText = displayedText.substring(0,
displayedText.length() - 1);
            }
            if (displayedText.length() == 0) {
                displayedText = "0";
            }
            calculator.displayField.setText(displayedText);
            calculator.resetFlag = false;
            return;
        }
        if (pressedButton.equals(".")) {
            if (!calculator.displayField.getText().contains(".")) {
                calculator.displayField.setText
(calculator.displayField.getText() + ".");
            }
            calculator.resetFlag = false;
            return;
        }
        if (pressedButton.equals("+/-")) {
            double val = Double.parseDouble
(calculator.displayField.getText());
            calculator.displayField.setText("" + -val);
            calculator.resetFlag = false;
            return;
        }

        if (pressedButton.equals("=")) {
            calculator.prevValue = operations.calculateResult();
            calculator.operatorUsed = "=";
            calculator.displayField.setText("" +
calculator.prevValue);
            calculator.resetFlag = true;
            return;
        }

        if (pressedButton.equals("+")) {
            calculator.prevValue = operations.calculateResult();
            calculator.operatorUsed = "+";
            calculator.displayField.setText("" +
calculator.prevValue);
            calculator.resetFlag = true;
            return;
        }

        if (pressedButton.equals("-")) {
            calculator.prevValue = operations.calculateResult();
            calculator.operatorUsed = "-";
            calculator.displayField.setText("" +
calculator.prevValue);
            calculator.resetFlag = true;
            return;
        }

        if (pressedButton.equals("/")) {
            calculator.prevValue = operations.calculateResult();
            calculator.operatorUsed = "/";
            calculator.displayField.setText("" +
calculator.prevValue);
            calculator.resetFlag = true;
            return;
        }

        if (pressedButton.equals("*")) {
            calculator.prevValue = operations.calculateResult();
            calculator.operatorUsed = "*";
            calculator.displayField.setText("" +
calculator.prevValue);
            calculator.resetFlag = true;
            return;
        }

        if (pressedButton.equals("sqrt")) {
            double totalVal = Math.sqrt(Double.parseDouble
(calculator.displayField.getText()));
            System.out.println("sqrt(" +
calculator.displayField.getText() + ") = " + totalVal);
            calculator.displayField.setText("" + totalVal);
            return;
        }

        if (pressedButton.equals("1/x")) {

            double totalVal = 1 / Double.parseDouble
(calculator.displayField.getText());
            System.out.println("1 / " + calculator.displayField.getText
() + " = " + totalVal);
            calculator.displayField.setText("" + totalVal);
            return;
        }
        calculator.displayField.setText(pressedButton);
    }
}