CS506 Highlighted Handouts Set 2

Lecture 1: Java Features ....................................................................................... 22

1.1

Design Goals of Java ...................................................................................................... 22

1.1.1

Right Language, Right Time ................................................................................... 22

1.1.2

Java - Buzzwords (Vocabulary) .............................................................................. 22

1.1.3

Java -- Language + Libraries .................................................................................. 22

1.1.4

Simple ..................................................................................................................... 23

1.1.5

Object-Oriented ....................................................................................................... 23

1.1.6

Distributed / Network Oriented .............................................................................. 23

1.1.7

Robust / Secure / Safe ............................................................................................. 23

1.1.8

Portable ................................................................................................................... 24

1.1.9

Support for Web and Enterprise Web Applications ............................................... 24

1.1.10

High-performance ................................................................................................... 24

1.1.11

Multi-Threaded ....................................................................................................... 24

1.1.12

Dynamic .................................................................................................................. 24

1.1.13

Java Compiler Structure .......................................................................................... 24

1.1.14

Java: Programmer Efficiency .................................................................................. 25

1.1.15

Microsoft vs. Java ................................................................................................... 25

1.1.16

Java Is For Real ....................................................................................................... 25

1.1.17

Lecture 2: Java Virtual Machine & Runtime Environment ............................. 26

2.1

Basic Concept ................................................................................................................. 26

2.1.1

Byte code ................................................................................................................ 26

2.1.2

Java Virtual Machine (JVM) .................................................................................. 27

2.1.3

Java Runtime Environment (JRE) .......................................................................... 27

2.1.4

2.2

Java Program Development and Execution Steps .......................................................... 28

2.2.1

Phase 1: Edit ........................................................................................................... 30

2.2.2

Phase 2: Compile .................................................................................................... 30

2.2.3

Phase 3: Loading ..................................................................................................... 30

2.2.4

Phase 4: Verify ........................................................................................................ 30

2.2.5

Phase 5: Execute ..................................................................................................... 31

2.2.6

2.3

Installation and Environment Setting ............................................................................... 31

2.3.1

Installation............................................................................................................... 31

2.3.2

Environment Setting ............................................................................................... 31

2.3.2.1

Temporary Path Setting .................................................................................................. 31

2.3.2.2

Permanent Path Setting ................................................................................................... 32

2.3.3

2.4

First Program in Java ....................................................................................................... 34

2.4.1

HelloWorldApp ....................................................................................................... 34

2.4.2

HelloWorldApp Described ..................................................................................... 35

2.4.3

Compiling and Running HelloWorldApp ............................................................... 35

2.4.4

Points to Remember ................................................................................................ 36

2.5

An Idiom Explained ....................................................................................................... 36

2.6

Lecture 3: Learning Basics ................................................................................... 38

3.1

Strings............................................................................................................................. 38

3.1.1

String Concatenation ............................................................................................... 38

3.1.2

Comparing Strings .................................................................................................. 38

3.2

Taking in Command Line Arguments ............................................................................ 39

3.3

Primitives vs. Objects ..................................................................................................... 40

3.4

Stack vs. Heap ................................................................................................................ 41

3.5

Wrapper Classes ............................................................................................................. 41

3.5.1

Wrapper Use ........................................................................................................... 42

3.5.2

Converting Strings to Numeric Primitive Data Types ............................................ 42

3.6

Selection & Control Structure ........................................................................................ 44

3.7

Reference: ....................................................................................................................... 44 Lecture 4: Object Oriented Programming .......................................................... 45

4.1

OOP Vocabulary Review ............................................................................................... 45

4.1.1

Classes .................................................................................................................... 45

4.1.2

Objects .................................................................................................................... 45

4.1.3

Constructor ............................................................................................................. 45

4.1.4

Attributes ................................................................................................................ 45

4.1.5

Methods .................................................................................................................. 45

4.2

Defining a Class .............................................................................................................. 45

4.3

Comparison with C++ .................................................................................................... 46

4.4

Task - Defining a Student class ...................................................................................... 47

4.5

Getters / Setters .............................................................................................................. 47

4.6

Using a Class ................................................................................................................... 48

4.6.1

Task - Using Student Class ..................................................................................... 49

4.7

More on Classes .............................................................................................................. 50

4.7.1

Static ....................................................................................................................... 50

4.7.2

Garbage Collection & Finalize ............................................................................... 50

4.7.2.1

Finalize ............................................................................................................................ 51

4.8

Reference: ....................................................................................................................... 54 Lecture 5: Inheritance ........................................................................................... 55

5.1

Comparison with C++ .................................................................................................... 55

5.2

Object - The Root Class ................................................................................................. 58

5.3

Polymorphism ................................................................................................................. 58

5.4

Type Casting .................................................................................................................. 60

5.4.1

Up-casting ............................................................................................................... 60

5.4.2

Down-casting .......................................................................................................... 60

5.5

Lecture 6: Collections ............................................................................................ 60

6.1

Collections Design ......................................................................................................... 61

6.2

Collection messages ....................................................................................................... 61

6.3

Array List ....................................................................................................................... 61

6.3.1

Useful Methods ....................................................................................................... 61

6.4

HashMap ........................................................................................................................ 63

6.4.1

Useful Methods ....................................................................................................... 63

6.5

6.6

Address Book .................................................................................................................. 65

6.6.1

Problem ................................................................................................................... 65