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					  Introduction to
Java Programming
                Introduction
–   Java applications and applets
–   Primitive data types
–   Java control flow
–   Methods
–   Object-oriented programming
 Fundamentals of Programming

– Introduction to Java
– Primitive Data Types and Operations
– Control Statements
– Methods
         Introduction to Java
 What  Is Java?
 Getting Started With Java Programming
  – Compiling and Running a Java Application
             What Is Java?
 History

 Characteristics   of Java
                    History
 James   Gosling
 Oak

 Java,   May 20, 1995, Sun World
 HotJava
  – The first Java-enabled Web browser
             Characteristics of Java
   Java is simple
   Java is object-oriented
   Java is distributed
   Java is interpreted
   Java is robust
   Java is secure
   Java is architecture-neutral
   Java is portable
   Java’s performance
   Java is multithreaded
   Java is dynamic
       Getting Started with Java
             Programming
A   Simple Java Application
 Compiling   Programs
 Executing   Applications
        A Simple Application
Example 1.1
//This application program prints Welcome
//to Java!
public class Welcome
{
  public static void main(String[] args)
  {
    System.out.println("Welcome to Java!");
  }
}
       Compiling Programs
 On command line
  – javac file.java

                  Java Source
                      File



                  Compiler



                      Bytecode
          Executing Applications
 On command line
  – java classname


                               Bytecode




      Java          Java                             Java
   Interpreter   Interpreter                      Interpreter
                                          ...
  on Windows      on Linux                      on Sun Solaris
               Example
javac Welcome.java

java Welcome

output:...
  Primitive Data Types and Operations
             Variables, and Constants
 Identifiers,
 Primitive Data Types
   – Byte, short, int, long, float, double, char, boolean
 Operators
   – +, -, *, /, %, +=, -=, *=, /=, %=, ++, --
 Expressions
 Styleand Documentation
 Syntax Errors, Runtime Errors, and Logic Errors
Numerical Data Types

byte          8 bits
short        16 bits
int         32 bits
long        64 bits
float        32 bits
double       64 bits
             Control Statements
SelectionStatements
  –Using if and if...else
  –Nested if Statements
  –Using switch Statements
  –Conditional Operator
Repetition   Statements
  –Looping: while, do, and for
  –Nested loops
  –Using break and continue
         Selection Statements
   if Statements
   switch Statements
   Conditional Operators
           if Statements
if (booleanExpression)
{
  statement(s);
}

Example:
if ((i >= 0) && (i <= 10))
{
  System.out.println("i is an “ +
    “integer between 0 and 10");
}
  The if...else Statement
if (booleanExpression)
{
  statement(s)-for-the-true-case;
}
else
{
  statement(s)-for-the-false-case;
}
                Repetitions
 while   Loops
   do Loops
 for   Loops
   break and continue
         Introducing Methods
                   Method Structure
A method is a                    modifier                     methodName

collection of                               returnValueType                parameters


statements that   method
                  heading
                            public static int max(int num1, int num2)
                            {
are grouped       method
                               int result = 0;

together to
                  body
                                if (num1 > num2)
                                  result = num1;

perform an                      else
                                  result = num2;

operation.                      return result;
                            }
                                      return value
       Declaring Methods

public static int max(int num1,
  int num2)
{
   if (num1 > num2)
     return num1;
   else
     return num2;
}
       Passing Parameters
void nPrintln(String message, int n)
{
  for (int i=0; i<n; i++)
    System.out.println(message);
}
 Object-Oriented Programming

– Objects and Classes
– Class Inheritance
           Exception Handling
 Exceptionsand Exception Types
 Claiming Exceptions
 Throwing Exceptions
 Catching Exceptions
 The finally Clause

				
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Description: java note includes java tokens and variable initialize and definitions