CS202 Introduction to Java

CS202 Introduction to Java

CS202 Introduction to Java

CS202 Introduction to Java

Classes in Java

Class Access Visibility

Members of a Class

Class Access Specifiers

 Member Accessibility

Similarities to C++

Similarities to C++

CS202 Introduction to Java

CS202 Minor Differences

CS202 Introduction to Java

CS202 Introduction to Java

Java Identifiers

What is an Identifier?

51 Java Reserved Words

Simplest Java class

Slide 20

What’s in a class heading?

Syntax for Declarations

Operators?

Operators? Equals() method

What about Arrays?

Arrays of Objects

Arrays are defined…

Arrays of class type…

Arrays

double[] salesAmt;
salesAmt = new double[6];

Array Definitions

Another Example

Declaring and Allocating an Array

Assigning values to array elements

What values are assigned?

Now what values are printed?

Initializer List

Passing Arrays as Arguments

Passing an Array as Arguments

Memory allocated for array

Parallel arrays

final  int  SIZE  = 50 ;
int [ ]  idNumber  = new  int  [ SIZE ] ;            // parallel arrays hold
float [ ]  hourlyWage = new  float [ SIZE ] ;    // related information

Partial Array Processing

More about Array Indexes

String[] groceryItems = new String[10];

String[] groceryItems = new String[10];

Date[] bigEvents = new Date[10];

Garbage Collection and Objects

Garbage Collection and Objects

Garbage Collectors: Efficiency?

Clarifying References

Types in Java

Primitive Wrapper Classes

Three Categories of Data

Categories of Responsibilities

Instance Data

Class Data

Local Data

Functions (ahhh Methods!)

Functions (ahhh Methods!)

Method Declaration Syntax

Methods

Some Definitions

More Definitions

More Definitions

Void Methods

Value-Returning Methods

Value-returning example

The This “Reference”

Constructors

Differences with Constructors

No Destructors!?

finalize() is not a destructor!

Inheritance

Accessing Base Class Members

Is there Hiding? Yes and No

Constructors in Hierarchies

If you have a finalize()…

A Java Application

Where do we get started? main

Main in which class?

Final Methods – a special case

Final Classes

More Definitions

An example

Another Example

Class Syntax

Overriding vs. Hiding

Polymorphism

Dynamic Binding

Dynamic Binding

Overriding or Overloading?

Abstract Base Classes

Abstract Base Classes

Interfaces in Java

“Implements” in Java

Multiple Inheritance!

What to use? So many choices!

Shadowing

Input and Output

Reference Types: A Review

Slide 102

Slide 103

Shallow Copy vs. Deep Copy

What’s the difference?

Separate deep copy

Copy Constructor: Different…

Java String Class

Actions of Java’s String class

"Why is String uppercase and..."

Assignment Statement Syntax

String concatenation (+)

Concatenation Example

Using Java output device

Java Input Devices

Using a Java Input Device

Interactive Input

Interactive Output continued

Inputting Numeric Values

Predefined Numeric Classes

Converting Strings to Numbers

Converting a String to a Double Value

Java Program

Java program continued

Additional String Methods

String Methods Continued

String Methods Continued

Slide 128

Relational operators w/Strings?

String methods

"String"

More String Methods

String Method compareTo

Values of each expression

Example of If statements
(same use of {}, if and else)

A sentinel-controlled loop

Slide 137

An end-of-file controlled loop

Slide 139

Flag-controlled loops

A flag-controlled loop

Slide 142

Exception Handling

Exceptions

Three Part Exception Handling

try-catch with Built-In Exception

try-catch with Exception Class

Class DataException

Execution of try-catch

Precedence

Slide 151

"// class List"

Unsorted and Sorted Lists

Methods for Class List

Observer Methods

Observer Methods Contd.

Transformer Method Insert

Before Inserting 64 into an Unsorted List

After Inserting 64 into an Unsorted List

Observer Method isThere

Transformer Method Delete

"public void delete(String item"

"// If item found,"

Iterator Methods

Straight Selection Sort

Selection Sort Algorithm

Selection Sort Code

"public void insert(String item"

Slide 169

Slide 170

"public boolean isThere(String item"

Comparable Interface

Slide 173

Slide 174

Slide 175

Initializing Static Members

Libraries