INTRODUCTION TO OBJECTS AND INPUT/OUTPUT - Java Programming: From Problem Analysis to Program Design - page 142

EXAMPLE 3-9

The output of the statement:

JOptionPane.showMessageDialog( null , "Hello World!", "Greetings",
JOptionPane.INFORMATION_MESSAGE);

is shown in Figure 3-9.

boxTitleString

messageStringExpression

messageType(Here it is, the
INFORMATION_MESSAGE icon)

FIGURE 3-9 Message dialog box showing its various components

Notice the INFORMATION_MESSAGE icon to the left of Hello World! and the word
Greetings in the title bar. After you click the OK button, the dialog box disappears.

EXAMPLE 3-10

Figure 3-10 shows the output of the following statement:

JOptionPane.showMessageDialog( null , "Amount Due = $" + 500.45,
"Invoice", JOptionPane.PLAIN_MESSAGE);

FIGURE 3-10 Message box with no icon

In the message dialog box in Figure 3-10, no icon appears to the left of the

messageStringExpression . This

is because the messageType is JOptionPane.

PLAIN_MESSAGE .