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| • Aselection control statement is used to alter the sequential flow of control. • The if and switch statements are two types of selection control. • The two versions of the if statement are if–then–else and if–then. • Aboolean expression contains conditional and boolean operators and evaluates to true or false. • Three boolean operators in Java are AND (&&), OR (||), and NOT (!). • DeMorgan’s laws state !(P &&Q) and !P || !Q are equivalent and !(P || Q) and !P && !Q are equivalent. • Logical operators && and || are evaluated by using the short-circuit evaluation technique. • Aboolean flag is useful in keeping track of program settings. • An if statement can be a part of the then or else block of another if statement to formulate nested if statements. • Careful attention to details is important to avoid illogically constructed nested if statements. • When the equality symbol == is used in comparing the variables of reference data type, we are comparing the addresses. • The switch statement is useful for expressing a selection control based on equality testing between data of type char, byte, short, or int. • The break statement causes the control to break out of the surrounding switch statement (note: also from other control statements introduced in Chap. 6). • The standard classes introduced in this chapter are: java.awt.Graphics java.awt.Point java.awt.Color java.awt.Dimension • The java.awt.Graphics class is used to draw geometric shapes. • The java.awt.Color class is used to set the color of various GUI components. • The java.awt.Point class is used to represent a point in two-dimensional space. • The java.awt.Dimension class is used to represent a bounding rectangle of geometric shapes and other GUI components. |