Core Java® Volume I–Fundamentals

129

Chapter 4: Objects and Classes ................................................................

130

Introduction to Object-Oriented Programming ..................................

4.1

131

Classes .........................................................................................

4.1.1

132

Objects .........................................................................................

4.1.2

133

Identifying Classes ....................................................................

4.1.3

133

Relationships between Classes ................................................

4.1.4

135

Using Predefined Classes .......................................................................

4.2

136

Objects and Object Variables ....................................................

4.2.1

139

The 

LocalDate

 Class of the Java Library .....................................

4.2.2

141

Mutator and Accessor Methods ..............................................

4.2.3

145

Defining Your Own Classes ...................................................................

4.3

145

An 

Employee

 Class .........................................................................

4.3.1

149

Use of Multiple Source Files ....................................................

4.3.2

149

Dissecting the 

Employee

 Class ......................................................

4.3.3

150

First Steps with Constructors ..................................................

4.3.4

152

Implicit and Explicit Parameters .............................................

4.3.5

153

Benefits of Encapsulation .........................................................

4.3.6

156

Class-Based Access Privileges ..................................................

4.3.7

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Contents

From the Library of Hristo Dimov Hristov

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156

Private Methods .........................................................................

4.3.8

157

Final Instance Fields ..................................................................

4.3.9

158

Static Fields and Methods .......................................................................

4.4

158

Static Fields .................................................................................

4.4.1

159

Static Constants ..........................................................................

4.4.2

160

Static Methods ............................................................................

4.4.3

161

Factory Methods ........................................................................

4.4.4

161

The 

main

 Method .........................................................................

4.4.5

164

Method Parameters ..................................................................................

4.5

171

Object Construction .................................................................................

4.6

172

Overloading ................................................................................

4.6.1

172

Default Field Initialization .......................................................

4.6.2

173

The Constructor with No Arguments .....................................

4.6.3

174

Explicit Field Initialization .......................................................

4.6.4

175

Parameter Names ......................................................................

4.6.5

176

Calling Another Constructor ...................................................

4.6.6

177

Initialization Blocks ...................................................................

4.6.7

181

Object Destruction and the 

finalize

 Method ...........................

4.6.8

182

Packages ....................................................................................................

4.7

183

Class Importation ......................................................................

4.7.1

185

Static Imports .............................................................................

4.7.2

185

Addition of a Class into a Package .........................................

4.7.3

189

Package Scope ............................................................................

4.7.4

190

The Class Path ...........................................................................................

4.8

193

Setting the Class Path ................................................................

4.8.1

194

Documentation Comments ....................................................................

4.9

194

Comment Insertion ...................................................................

4.9.1

195

Class Comments ........................................................................

4.9.2

195

Method Comments ...................................................................

4.9.3

196

Field Comments ........................................................................

4.9.4

196

General Comments ...................................................................

4.9.5

198

Package and Overview Comments .........................................

4.9.6

198

Comment Extraction .................................................................

4.9.7

200

Class Design Hints ..................................................................................

4.10

Contents

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From the Library of Hristo Dimov Hristov

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