How can I fix a floating decimal error in Java?

Question

I am trying to create a simple program just using the built-in Math methods, but everytime I run it I get a floating decimal error, so I wonder what a floating decimal is and how error occurs.

Here is my code:

private void btnCalculateActionPerformed(java.awt.event.ActionEvent evt) {
    double dblSquareRoot = Double.parseDouble(lblSquareRoot.getText());
    double dblRandomNumber = Double.parseDouble(lblRandomNumber.getText());
    double dblSquareNumber = Double.parseDouble(lblSquareNumber.getText());
    double dblRoundUp = Double.parseDouble(lblRoundUp.getText());
    double dblRoundDown = Double.parseDouble(lblRoundDown.getText());

    lblOutputSquareRoot.setText("" + Math.sqrt(dblSquareRoot));
    lblOutputSquareNumber.setText("" + Math.pow(dblSquareNumber, 2));
    lblOutputRoundUp.setText("" + Math.ceil(dblRoundUp));
    lblOutputRoundDown.setText("" + Math.floor(dblRoundDown)); 
}                                    

private void btnGenerateActionPerformed(java.awt.event.ActionEvent evt) {
    double dblRandomNumber = (Math.random() * 101.0);

    txtRandomNumber.setText("" + df.format(dblRandomNumber));
    txtSquareRoot.setText("" + df.format(dblRandomNumber));
    txtSquareNumber.setText("" + df.format(dblRandomNumber));
    txtRoundUp.setText("" + df.format(dblRandomNumber));
    txtRoundDown.setText("" + df.format(dblRandomNumber));

    df.format = "###.00";
}

error-

Exception in thread "AWT-EventQueue-0" java.lang.NumberFormatException: For input string: "Square Root"
  at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:1250)
  at java.lang.Double.parseDouble(Double.java:540)
  at mathMethods.btnCalculateActionPerformed(mathMethods.java:230)
  at mathMethods.access$100(mathMethods.java:13)
  at mathMethods$2.actionPerformed(mathMethods.java:97)
  at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
  at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
  at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
  at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
  at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
  at java.awt.Component.processMouseEvent(Component.java:6516)
  at javax.swing.JComponent.processMouseEvent(JComponent.java:3320)
  at java.awt.Component.processEvent(Component.java:6281)
  at java.awt.Container.processEvent(Container.java:2229)
  at java.awt.Component.dispatchEventImpl(Component.java:4872)
  at java.awt.Container.dispatchEventImpl(Container.java:2287)
  at java.awt.Component.dispatchEvent(Component.java:4698)
  at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
  at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
  at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
  at java.awt.Container.dispatchEventImpl(Container.java:2273)
  at java.awt.Window.dispatchEventImpl(Window.java:2719)
  at java.awt.Component.dispatchEvent(Component.java:4698)
  at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:735)
  at java.awt.EventQueue.access$200(EventQueue.java:103)
  at java.awt.EventQueue$3.run(EventQueue.java:694)
  at java.awt.EventQueue$3.run(EventQueue.java:692)
  at java.security.AccessController.doPrivileged(Native Method)
  at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
  at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
  at java.awt.EventQueue$4.run(EventQueue.java:708)
  at java.awt.EventQueue$4.run(EventQueue.java:706)
  at java.security.AccessController.doPrivileged(Native Method)
  at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
  at java.awt.EventQueue.dispatchEvent(EventQueue.java:705)
  at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
  at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
  at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
  at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
  at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
  at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)

What do you mean by "floating decimal error"? Please add the StackTrace to your question and try to desribe the error more detailed and what you are trying to achieve with the posted code. — Binkan Salaryman, Aug 06 '15 at 15:19
all the code does is creates a random number between 0-100 and then outputs the square rooted, squared, and rounded version of the number to seperate labels — Jeffrey Cao WatsYourPowerLvl, Aug 06 '15 at 15:24
That isn't the full stacktrace, we need all of it (unless you know what you're doing) — Binkan Salaryman, Aug 06 '15 at 15:29
assuming ``double dblSquareRoot = Double.parseDouble(lblSquareRoot.getText());`` is line 230 of mathMethods.java, you are trying to parse the string ``"Square Root"`` to a ``double``. As this isn't possible, check your program logic; you may take the wrong number source or expecting the label to display a number. — Binkan Salaryman, Aug 06 '15 at 15:35

score 1 · Accepted Answer · answered Aug 06 '15 at 15:30

1

It looks like you're trying to parse strings from the labels instead of the text fields. Take a look at the variable names.

answered Aug 06 '15 at 15:30

Zymus

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For the future, learn how to use the [stack trace and debugger](http://stackoverflow.com/questions/3988788/what-is-a-stack-trace-and-how-can-i-use-it-to-debug-my-application-errors). – Binkan Salaryman Aug 06 '15 at 15:36

How can I fix a floating decimal error in Java?

1 Answers1