Using Objects - Java Concepts - page 101

getWidth
java.lang.String
length
replace
toLowerCase
toUpperCase
javax.swing.JComponent
paintComponent
javax.swing.JFrame
setDefaultCloseOperation

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REVIEW EXERCISES

΢ Exercise R2.1. Explain the difference between an object and an object
reference.

΢ Exercise R2.2. Explain the difference between an object and an object
variable.

΢ Exercise R2.3. Explain the difference between an object and a class.

΢΢ Exercise R2.4. Give the Java code for constructing an object of class
Rectangle , and for declaring an object variable of class Rectangle .

΢΢ Exercise R2.5. Explain the difference between the=symbol in Java and in
mathematics.

΢΢΢ Exercise R2.6. Uninitialized variables can be a serious problem. Should
you always initialize every int or double variable with zero? Explain
the advantages and disadvantages of such a strategy.

΢΢ Exercise R2.7. Give Java code to construct the following objects:

a. A rectangle with center (100, 100) and all side lengths equal to 50

b. A string ÐHello, Dave!Ñ

Create objects, not object variables.

΢΢ Exercise R2.8. Repeat Exercise R2.7, but now define object variables that
are initialized with the required objects.