25

Thread Safety Utilities

Features of the Thread Safety Classes  Methods

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25.1 Features of the Thread Safety Classes

JCMessageHelper lets you build a message dialog based on JOptionPane. The advantages of the JCMessageHelper are:

• JCMessageHelper invokes JOptionPane in a thread-safe manner.
• You can set an audible indication when the dialog appears as a parameter in the constructor.
• JCMessageHelper utilizes JCSwingRunnable, an abstract runnable class that provides the run() method. You can create an object of this type, and call the runSafe method to get it going.

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25.2 Methods

JCMessageHelper

JCMessageHelper has static methods that resemble those in JOptionPane. These are:

showError()	Shows an error message, given a title and the message String as parameters.
showInformation()	Parameters are two Strings: title and message. The message appears in an information dialog.
showWarning()	Parameters are two Strings: title and message. The message appears in a warning dialog.
showMessage()	There is an optional first parameter that lets you specify a parent Component. The next two parameters are Strings, title and message. The next parameter is an int specifying the message type, and the optional last parameter is a Boolean that specifies whether to emit an audible beep when the dialog appears. The possible message types are javax.swing.JOptionPane.ERROR_MESSAGE javax.swing.JOptionPane.INFORMATION_MESSAGE javax.swing.JOptionPane.WARNING_MESSAGE javax.swing.JOptionPane.QUESTION_MESSAGE javax.swing.JOptionPane.PLAIN_MESSAGE   See javax.swing.JOptionPane for a description of the various dialogs.

JCSwingRunnable

run()

Since this class implements Runnable and is used to create a thread, its run() method will be called to start the thread.