Teach Yourself Java in 21 Days

Day

4

Working with Objects

61

Creating New Objects .............................................................................. 62

Using new ............................................................................................ 63

What new Does ................................................................................... 64

A Note on Memory Management ........................................................ 64

Accessing and Setting Class and Instance Variables ................................... 65

Getting Values ..................................................................................... 65

Changing Values .................................................................................. 65

Class Variables ..................................................................................... 66

Calling Methods ....................................................................................... 67

Class Methods ..................................................................................... 69

References to Objects ............................................................................... 70

Casting and Converting Objects and Primitive Types .............................. 71

 Casting Primitive Types ...................................................................... 71

 Casting Objects .................................................................................. 72

Converting Primitive Types

to Objects and Vice Versa ................................................................. 73

Odds and Ends ......................................................................................... 73

Comparing Objects ............................................................................. 74

Copying Objects .................................................................................. 75

Determining the Class of an Object ..................................................... 76

The Java Class Libraries ............................................................................ 76

Summary .................................................................................................. 77

Q&A ........................................................................................................ 78

030-4 FM

1/29/96, 8:11 PM

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