java programming part 1mcsc.sc.mahidol.ac.th/courses/cps/slides/java.pdf · 3 cpu executes...

Chaiwoot Boonyasiriwat

January 22, 2020

Computer Programmingusing Java

2

▪ Problem definition: determine what the problem really is, set the goals

▪ Analysis: determine inputs, outputs, and relevant factors

▪ Design: describe methods used, provide detail of all steps required to turn input into output

▪ Implementation: write a code corresponding to the designed algorithm

▪ Testing: validate program using test cases▪ Redo analysis/design/implementation if

program fails the validation test

Problem Solving using Computer

3

Flowchart: Average

4

Flowchart: Greeting

5

Java Programming Cycle

Suchato (2011, p. 23)

Text editor or IDE JDK: javac.exe JRE: java.exe

IDE = integrated development environment

6

Running Java Program

Suchato (2011, p. 22)

Write Once, Run Anywhere (with JRE installed)

JVM = Java Virtual Machine

JRE = Java Runtime Environment

7

▪ A Hello World program is conventionally the first program anyone should learn to develop when starting to learn a new programming language.

▪ The Hello World program can be written in Java as follows.

File: Hello.java

class Hello {

public static void main(String[] args) {

System.out.println("Hello World");

}

}

Hello World Program

8

▪ Java source code:• File name must be exactly the same as the

class name (case sensitive)• File extension must be .java

▪ Compilation: javac [file name of source code]

• Example: javac Hello.java

▪ Execution: java [class name]• Example: java Hello

Compiling and Running Java Program

9

"Command line or console or terminal is a text-based interface that forwards commands from the user to the operating system."Commands for PowerShell or Terminal:▪ ls list the files and directories (folders) in

the current directory▪ cd change the current directory to

another directory▪ mkdir make a new directory▪ cp copy files or directories

Command Line/Terminal

https://www.ionos.com/digitalguide/server/know-how/windows-cmd-commands/

10

▪ pwd present working directory▪ mv move files or directories▪ rm remove files or directories

Command Prompt (cmd.exe) Commands▪ dir list the files and directories (folders) in

the current directory▪ cd change the current directory▪ mkdir make a new directory▪ copy copy files or directories▪ move move files or directories

Terminal Commands

11

> cd change the current directory to home directory of the user

> cd java change the current directory to directory java which is a sub-directory in the current directory

> cd .. change the current directory to one level up

If you are in /home/user/java, "cd .." will move you to /home/user.

Examples: cd

12

▪ A Java program must contain• a class definition using the keyword class• the main method defined within the class

▪ Definition of a class named Hello:class Hello

{

... main(...)

{

...

}

}

Basic Structure of a Java Program

keyword

class name

block of class

block of method

method main

13

// import java.lang.System;

class Hello

{

public static void

main(String[] args)

{

System.out.print("Hello");

}

}

Hello World Program Revisited

keyword

methodclass variable literal

14

KeywordsKeywords cannot be used as identifier

https://docs.oracle.com/javase/tutorial/java/nutsandbolts/_keywords.html

15

Identifiers"Identifiers are the names of variables, methods, classes, interfaces"

Naming Rules for Identifier

If these rules are violated, a compilation error will occur.

http://www.cafeaulait.org/course/week2/08.html

Suchato (2011, p. 39)

16

If these conventions are violated, a compilation error will NOT occur.

Naming Conventions for Identifiers

17

Literals"Literal is notation for representing a fixed value in source code."

Examples:▪ 0, 100, -2 int literals▪ 1L, 50L, 321l long literals▪ 3.14F, 1.0f, 2.0E4F float literals▪ 3.14, 1D, 2d, 2.0E2 double literals▪ true, false boolean literals▪ 'a', '4', '$', '\n' char literals▪ "Hello","1","//","/* */" String literals

https://en.wikipedia.org/wiki/Literal_(computer_programming)

18

Type Value/Range Sizeboolean true, false 1 bytechar 'a', 'd', '\n' 2 bytesbyte [-128, 127] 1 byteshort [-32768, 32767] ~ 3.2104 2 bytesint [-2147483648, 2147483647] 4 bytes

~ 2.1109

long [-263, 263-1] ~ 9.21018 8 bytesfloat 4 bytesdouble 8 bytes

Primitive Data Types

19

▪ Since data in computers are represented as binary numbers, computers need to know how to convert binary numbers to characters.

▪ This is done by character encoding called Unicode (universal coded character set)

Character Encoding

20

Escape Characters

Example: Escape.java

class Escape {


System.out.println("Hello\nWorld\tHello");

}

}

21

Examples: declare one variable per statementbyte a;

short b;

int c;

long d;

char e;

Examples: declare multiple variables per statementfloat a, b, c;

double pi, r, area;

boolean yes, no;

Variable Declaration

22

Examples: declare variables and assign the value in the same statementint a = 1;

long b1 = 1L, _b = 20l;

boolean yes = true;

float c = 12.3F, _c = 1.0e2f;

double pi = 3.14, r = 1.0;

double value = 1.234E10;

String name = "Jack";

Declaration and Assignment

23

▪ Final variables are variables that can be assigned a value only once.

▪ Final variables are declared using the keyword final in front of the type and variable name.

▪ Conventionally, final variables are named using all uppercase letters and words are separated by underscore _.

▪ Examples:final double PI = 3.14159;

final double YOUNG_MODULUS;

Final Variables

24

▪ Variables that have been declared but have not been assigned a value cannot be used.

▪ Using an un-initialized variable will result in a compilation error.

▪ Example:int a = 1;

int b, c;

c = a + b;

Un-initialized Variables

25

▪ Values can be manipulated using built-in operators including• arithmetic operators: +, -, *, /, %• logical operators: &&, ||, !• comparison operators: ==, !=, >, <, >=, <=• grouping operators: parentheses ( )

▪ "Binary operators are operators that required 2 operands." Examples: +, -, *, /, %, &&, ||, ==, !=, >, <, >=, <=

▪ "Unary operators are operators that required only 1 operand." Examples: !

Operators

26

Addition a + b

Subtraction a – b

Multiplication a * b

Division a / b

Modulo a % b

(modulo = remainder after division)

Arithmetic Operators

27

a==1 && b ==2 AND operatora==1 || b ==2 OR operator!b NOT b

Logical Operators

28

a == b Is a equal to b?a != b Is a not equal to b?a > b Is a greater than b?a < b Is a less than b?a >= b Is a greater than or equal to b?a <= b Is a less than or equal to b?

Comparison Operators

29

a += 1; a = a+1

a -= 1; a = a-1

a *= 1; a = a*1

a /= 2; a = a/2

a %= 3; a = a%3

Java Language Specification:E1 op= E2 is equivalent to E1 = (T)((E1) op (E2)) where E1 and E1 are expressions, T is the type of E1, op is arithmetic operator (+, -, *, /, %)

Compound Assignment Operators

30

a = (1<3) ? 2 : 4; a = 2

a = (1>3) ? 2 : 4; a = 4

Conditional Operator

Deitel and Deitel (2010, p. 109)

31

++a Increment a by 1, then use the newvalue of a

a++ Use the current value of a, then increase a by 1

--a Decrement a by 1, then use the newvalue of a

a-- Use the current value of a, then decrease a by 1

Increment/Decrement Operators


32

▪ Expressions only contain identifiers, literals, operators (arithmetic or logical operators), method call (e.g., print())

▪ Expressions can be evaluated to a value.▪ "A statement is a complete sentence that

causes an action to occur."▪ Statements must end with semicolon ;▪ Examples of statements:int a; a = 10;

System.out.print(a);

Expression and Statement

33

▪ Order of execution of operators in an expression is exactly determined by the precedence and association rules.

▪ "Each operator is assigned a precedence level."

▪ "Operators with higher precedence levels are executed before ones with lower precedence levels."

Precedence Rules

Suchato (2011, p. 71)

34

▪ Order of execution of operators with the same precedence level are determined by the association rules of the operators.

▪ "The association rule indicates whether operators to the left or to the right are to be executed first."

Association Rules

Suchato (2011, p. 71)

35

Precedence/Association

Suchato (2011, p. 71)

36

Precedence/Association

https://introcs.cs.princeton.edu/java/11precedence/

37https://introcs.cs.princeton.edu/java/11precedence/

38

https://docs.oracle.com/javase/tutorial/java/nutsandbolts/operators.html

39

▪ 1+2*3 = 1+(2*3) = 1+6 = 7

▪ 1*2-6/2 = (1*2)-(6/2) = 2-3 = -1

▪ 1+2>2+3 = (1+2)>(2+3) = 3>5 = false

▪ 1+(-2)*3 = 1 + (-2*3) = 1 – 6 = -5

Example 1: Precedence

40


Suchato (2011, p. 74)

41


Suchato (2011, p. 74)

42

▪ Various universal constants and mathematical functions can be used via the class Math.

▪ These functions include abs, round, ceil, floor, exp, max, min, pow, sqrt, sin, cos, tan, asin, acos, atan etc.

▪ Examples:double a = Math.PI * Math.sin(1);

a = exp(-10);

double b = Math.min( -1, 10);

For a complete list of methods of class Math, see https://docs.oracle.com/javase/7/docs/api/java/lang/Math.html

Mathematical Methods

43

Distance d between 2 points in 3D space and can be computed from

Distance in 3D Space

Suchato (2011, p. 75)

44

File: Distance2d.java

Distance in 3D Space

Suchato (2011, p. 75)

45

There are 2 types of type conversion▪ implicit/automatic type conversion

• no loss of magnitude of numeric value• Example: long a = 100;

▪ explicit type conversion• magnitude of numeric value may be lost• a cast operator is required for conversion• Example: short a = (short) 123;

Type Conversion

Suchato (2011, p. 75)

46

Type Value/Range Sizeboolean true, false 1 bytechar 'a', 'd', '\n' 2 bytesbyte [-128, 127] 1 byteshort [-32768, 32767] ~ 3.2104 2 bytesint [-2147483648, 2147483647] 4 bytes

~ 2.1109

long [-263, 263-1] ~ 9.21018 8 bytesfloat 4 bytesdouble 8 bytes

Primitive Data Types

47

▪ "Widening primitive conversion does not lose information about the overall magnitude of a numeric value but may result in loss of precision."

Widening Primitive Conversion

https://docs.oracle.com/javase/specs/jls/se7/html/jls-5.html

48

▪ "Narrowing primitive conversion may lose information about the overall magnitude of a numeric value and may also lose precision and range."

Narrowing Primitive Conversion

https://docs.oracle.com/javase/specs/jls/se7/html/jls-5.html

49

A = automatic type conversionC = cast operator is requiredX = type conversion is not allowed

* loss of precision might occur from conversion

Type Conversion Table

Suchato (2011, p. 83)

50

Rules governing the evaluation of expressions with multiple data types are as follows.

Expression with Multiple Data Types

Suchato (2011, p. 85)

51

Examples

Expression with Multiple Data Types

Suchato (2011, p. 85)

52

Although integer literals are treated by default as int, in some cases integer literals are treated by the compilers as byte or short.

An integer literal in the range [-128,127] is treated as byte when it is assigned to a variable of type byte.

byte a = 127; // OK

byte b = 128; // Wrong: 128 = int

Assignment Statement

53

An integer literal in the range [-32768,32767] is treated as short when it is assigned to a variable of type short.

short a = 32767; // OK

short b = 32768; // Wrong

// 32768 = int

Assignment Statement (con.)

54

An integer literal in the range [0, 65535] is treated as char when it is assigned to a variable of type char. (size of char is 2 bytes or 16 bits)

char a = 65535; // OK

char b = 65536; // Wrong

// 65536 = int

Assignment Statement (con.)

Floating-Point Numbers

55

IEEE Standard for Floating-Point Arithmetic (IEEE 754) defines▪ arithmetic formats: sets of binary and decimal floating-

point data, which consist of• normal numbers, signed zeros and subnormal numbers• signed infinities, and "not a number" (NaN)

▪ interchange formats: encodings (bit strings) used to exchange floating-point data

▪ rounding rules: properties to be satisfied when rounding numbers during arithmetic and conversions

▪ operations: operations on arithmetic formats▪ exception handling: indications of exceptional conditions

(such as division by zero, overflow, etc.)

https://en.wikipedia.org/wiki/IEEE_754

IEEE 754 Format

56Reference: http://en.wikipedia.org/wiki/IEEE_floating_point

IEEE 754-1985

57

Precision: The number of decimal digits precision is calculated via number_of_mantissa_bits * . Thus ~7.2 and ~15.9 for single and double precision respectively.

Reference: http://en.wikipedia.org/wiki/IEEE_754-1985

Single precision

Double precision

Single-Precision Floating-Point Format

58

▪ minimum positive normal number▪ minimum positive subnormal number ▪ precision =

https://en.wikipedia.org/wiki/Single-precision_floating-point_format

Example: Normal Numbers

59https://en.wikipedia.org/wiki/Single-precision_floating-point_format

Example: Subnormal Numbers


Example: Zeros, Infinities, NaNs


62

▪ Decimal number system cannot exactly represent some fractions, e.g. 1/3, 1/11, 1/13

▪ These fractions become repeating decimals, e.g., 1/3 = 0.33333...

▪ Binary number system cannot also exactly represent some fractions, e.g., 1/5, 1/10

▪ To convert a decimal fraction into a binary fraction, simply multiply only the fraction by 2 repeatedly and record the whole number

Limitation on Floating Point

63

2 x 0.1 0.2 x 0.2 02 x 0.4 02 x 0.8 02 x 1.6 12 x 1.2 12 x 0.4 02 x 0.8 02 x 1.6 12 x 1.2 1

0.4 0

Decimal to Binary Fraction

Therefore, 0.1 cannot be exactly represented using single-precision floating-point format (float) or double-precision floating-point format (double).

64

▪ Since some real numbers cannot be exactly represent using float or double, comparing two floating-point numbers is something that should be avoided.

▪ Instead, use the absolute of the difference to compare two numbers instead.

▪ Example: d = |a-b|if d < then a is equal to botherwise a is not equal to b

Comparing Floating-Point Numbers

65

class CompareFloat {


float a = .1f+.1f+.1f+.1f+.1f+.1f+.1f;

float b = .1f*7;

boolean c = a==b;

float d = Math.abs(a-b);

boolean e = d < 1.0e-7f;

System.out.println(c);

System.out.println(e);

}

}

Example: Floating-Point Operations

66

▪ Each numeric data type has a corresponding valid range of numerical values.

▪ When a value larger than the largest value of a data type is assigned to a variable, an overflow occurs.

▪ When overflow occurs for integer types (byte, short, int, long), a wrap-around of value occurs.

▪ For float and double, overflow will result in the special value of POSITIVE_INFINITY or NEGATIVE_INFINITY

Overflow

67

class ByteOverflow {


byte a = 127;

a++;

System.out.println(a);

a = -128;

a--;


}

}

Example: Byte Overflow

68

class ShortOverflow {


byte a = 32767;

a++;


a = -32768;

a--;


}

}

Example: Short Overflow

69

class FloatOverflow {


float a = 3.4e38f;


a *= 10;


a = -3.4e38f;


a *= 10;


}

}

Example: Float Overflow

70

▪ The smallest positive subnormal number for float is about 1.4 x 10-45

▪ The smallest positive subnormal number for double is about 4.9 x 10-324

▪ When a value smaller than these numbers is assigned to a variable, an underflow occurs and the value 0 is assigned to the variable instead.

Underflow

71

class FloatUnderflow {


float a = 1.4e-45f;


a /= 10;


float b = -1.4e-45f;

System.out.println(b);

b /= 10;


}

}

Example: Float Underflow

72

class DoubleUnderflow {


double a = 4.9e-324;


a /= 10;


double b = -4.9e-324;


b /= 10;


}

}

Example: Double Underflow

73

▪ For integer types, division by zero will lead to runtime error of type divide-by-zero arithmetic exception.

▪ For floating-point types, division by zero will lead to signed infinities.

Division By Zero

74

class IntegerDivideByZero {


int a = 1/0;

}

}

int: Division by Zero

75

class FloatDivideByZero {


float a = 1.0f/0.0f;


a = -1.0f/0.0f;


}

}

float: Division by Zero

76

▪ In mathematics, indeterminate forms include 0/0, /, 0, 1, - , 00, 0

▪ For integer types, indeterminate form 0/0 will results in a runtime error of type divide-by-zero arithmetic exception.

▪ For floating-point types, indeterminate forms will result in a special Not-a-Number (NaN).

Indeterminate Form

77

class FloatIndeterminate {


float a = 0.0f/0.0f;


a = -0.0f/0.0f;


float b = 1.0f/0.0f;

a = b/b;


a = b * 0.0f;


}

}

float: Not-a-Number

78

▪ Real-world objects (e.g., cars, TV) have both attributes (data) and functionalities (methods).

▪ These objects can be classified as classes of objects.

▪ An object is an instance of a class.▪ In Java, a class is a non-primitive data type that

can be created using the class keyword.▪ A class can contain both data (variables) and

methods. This is called encapsulation which is one of the fundamental concept of object-oriented programming (OOP).

Class and Object

79

▪ Constructors: special methods used to initialize objects

▪ Variables• instance variables: belong to an instance• static variables: shared among all instances

▪ Methods• instance methods: called via an instance• static variables: called via class name

Member variables and methods must be accessed using the . operator.

Members of a Class

80

class Point {

public double x, y;

public static Point o = new Point(0,0);

public Point(double x, double y) {

this.x = x;

this.y = y;

}

public double distance(Point p) {

double dx = x – p.x;

double dy = y – p.y;

return Math.sqrt(dx*dx+dy*dy);

}

}

Point: Class Definition

81

Point: UML Class Diagram

Point

+x: double

+y: double

+o: Point

+Point(x: double, y: double)

+distance(p:Point): double

UML (Unified Modeling Language) class diagram contains 3 parts: (1) class name, (2) variables, (3) methods. (+ = public, underline = static)

82

class UsingPoint {

public static void main(String[] a) {

Point p1 = new Point(1, 2);

Point p2 = new Point(4, 3);

double d = p1.distance(p2);

System.out.println(d);

d = p1.distance(Point.o);

System.out.println(d);

}

}

Point: Usage

83

▪ When a class is used to declare a variable, that variable is called object which is an instance of the class. That class is said to be instantiated.

▪ Example:Point p = new Point(1,2);

An Instance of a Class

class object

- keyword- operator for creating object

constructor: special methodused for creating object

84

▪ Data members or variables of a class can be classified as• instance variables: can be accessed only via

an instance of the class, i.e., an objectExample: Point p = new Point(1,2);

double x = p.x;

• class or static variables: can be accessed only via the class name and are shared among all instances of the classExample: Point p = Point.o;

Data Members of a Class

85

“All programs could be written in terms of only three control structures:”▪ Sequence structure▪ Selection structure

• if, if-else statements• switch statement

▪ Repetition structure• for statement• while statement• do-while statement

Control Structures

Remark: if, else, switch, for, do, while are keywords

86

Statements are executed one after another.

Sequence Structure


a = 1

b = 2

c = a + b

a = 1;

b = 2;

c = a + b;

Process 1

Process 2

Process 3

Flo

wch

art

Terminator

Terminator

Begin

End

Flow line

87

Selection Structure: if


b = 1

false

if (a > 0) {

b = 1;

}

Decision a > 0

Connector

true

if (a > 0)

b = 1;or

Flow line

88

Selection Structure: if…else


b = 1false

a > 0true

if (a > 0)

b = 1;

else

b = 2;

b = 2

if (a > 0) {

b = 1;

} else {

b = 2;

}

89

Nested if

Suchato (2011, p. 145)

90

Example: Nested if

if (a > 0) {

if (b > 1) {

c = 1;

}

}

if (a > 0 && b > 1) {

c = 1;

}

is equivalent to

91

if-else-if

Suchato (2011, p. 148)

is equivalent to

92

if-else-if Flowchart

action1

F

expr1T

action2expr2

expr3

F

93

Flowchart: Absolute Value

94

switch: syntax

switch (expression) {

case constant expression:

// do something

break;

case constant expression:

// do something

break;

default:

// do something

break;

}

95

switch: Example

switch(a){

case 1:

System.out.println("a = 1");

break;

case 2:

System.out.println("a = 2");

break;

default:

System.out.println("a is not 1,2");

break;

}

96

switch: Flowchart

https://chortle.ccsu.edu/java5/Notes/chap43/ch43_8.html

97

Repetition Structure: while


a++

false

a < 10true

a = 0;

while (a < 10) {

a++;

}

98

Repetition Structure: do…while


a++

false

a < 10true

a = 0;

do {

a++;

} while (a < 10);

a = 0;

99

Repetition Structure: for


sum = 0;i = 0;

false

i 10true

sum = 0;

for (i = 1; i<=10; i++) {

sum += i;

}

sum+=i i++

100

char charAt(int index)

returns the char value at the specified indexint compareTo(String str)

compares two strings lexicographicallyint compareToIgnoreCase(String str)

compares two strings lexicographically, ignoring case differences

String concat(String str)

concatenates the specified string to the end of this string

Methods of String Class

https://docs.oracle.com/javase/9/docs/api/java/lang/String.html

101

boolean startsWith(String prefix)

tests if this string starts with the specified prefixboolean endsWith(String suffix)

tests if this string ends with the specified suffixint indexOf(int ch)

returns the index within this string of the first occurrence of the specified character

int indexOf(String str)

returns the index within this string of the first occurrence of the specified substring



102

int lastIndexOf(int ch)

returns the index within this string of the last occurrence of the specified character

int lastIndexOf(String str)

returns the index within this string of the last occurrence of the specified substring

int length()

returns the length of this stringString substring(int begin, int end)

returns a string that is a substring of this string



103

String toLowerCase()

converts all characters to lower caseString toUpperCase()

converts all characters to upper caseString trim()

returns this string without leading and trailing whitespace



104

String valueOf(boolean b)

String valueOf(char c)

String valueOf(int i)

String valueOf(long l)

String valueOf(float f)

String valueOf(double d)

converts the input to a string representation

Static Methods of String


105

Static Data:int MAX_VALUE

the maximum value an int can have, 231-1int MIN_VALUE

the minimum value an int can have, -231

Constructor:Integer(int value)

Integer(String s)

constructs a newly allocated Integer object

Integer Class

https://docs.oracle.com/javase/7/docs/api/java/lang/Integer.html

106

int parseInt(String s)

parses the string argument as an intString toBinaryString(int i)

returns string representation of the integer argument as an unsigned integer in base 2

String toHexString(int i)


String toOctalString(int i)


Static Methods of Integer


107

String toString(int i)

returns a String object representing the specified integer

Static Methods of Integer


108

double MAX_VALUE

the largest positive finite value of type double(2-2-52)x21023

double MIN_VALUE

the smallest positive nonzero value of type double, 2-1074

double NaN

Not-a-Number (NaN) value of type doubledouble NEGATIVE_INFINITY

negative infinity of type doubledouble POSITIVE_INFINITY

positive infinity of type double

Static Data of Double Class

https://docs.oracle.com/javase/7/docs/api/java/lang/Double.html

109

boolean isInfinity(double v)

returns true if the specified number is infinitely large in magnitude, false otherwise

boolean isNaN(double v)

returns true if the specified number isNot-a-Number (NaN) value, false otherwise

double parseDouble(String s)

parses input String into a doubleString toString(double d)

returns a string representation of double argumentDouble valueOf(String s)

returns Double object from the input string

Static Methods of Double

https://docs.oracle.com/javase/7/docs/api/java/lang/Double.html

110

▪ Primitive data types• integer data: use a==b, a!=b• floating-point data: use |a-b| < c where c is a small number, e.g. 10-6

▪ Non-primitive data types• (a == b) returns true only if a and b

contains the same reference to the same object in the heap memory

Equality Testing

111

▪ ==tests for reference equality▪ .equals() tests for value equality▪ Objects.equals() checks for null

before calling .equals()

Equality Testing for

Non-Primitive Data Type

https://stackoverflow.com/questions/513832/how-do-i-compare-strings-in-java

112

// These two have the same value

new String("test").equals("test") // true

// but they are not the same object

new String("test") == "test" // false

new String("test") == new String("test") // false

// String literals are interned by the compiler

// Unique String literals are in a String pool

"test" == "test" // true

// String literals are concatenated by the

// compiler and the results are interned.

"test" == "te" + "st" // true

// Compare String value using Objects.equals()

Objects.equals("test",new String("test")) // true

Objects.equals(null, "test") // false

Objects.equals(null, null) // true

Equality Testing for String

https://stackoverflow.com/questions/513832/how-do-i-compare-strings-in-java

▪ "A running program uses two regions of memory to store data: stack and heap."

▪ "Stack is a last-in, first-out (LIFO) data structure."

▪ "Data can be added to and deleted only from the top."

▪ Placing a data item at the top of stack is called pushing the item onto the stack.

▪ Deleting an item from the top of stack is called popping the item from the stack.

▪ Stack memory stores several types of data• value of certain type of variables, e.g., local

Stack and Heap

Stack

Solis and Schrotenboer (2018)

▪ "Data can be stored and removed from the heap in any order."

Heap


Garbage Collector (GC)


117

JavaIdentifiers:name of package, class, variable,method, label, interface, enum

Control FlowStatements

ModifiersAccess modifiers:public, private,protected, default

Non-access modifiers:static, final, abstract,synchronized, volatile

Types

Primitive/Value Types:boolean, char, byte, short, int, long,float, double

Non-primitive/Reference Types:array, enum, class, interface

Decision-Making:if-then, if-then-else, switch

Looping:while, do-while, for

Branching:break, continue, return

Operators

+,-,*,/,%,++,--

,!,~,=,+=,=,*=,/=,%=,

&=,^=,|=,<<=,>>=,>>>=,==,!=,>,<,>=,

<=,&&,||,?:,(),[],.,new,instanceof

Exception

Checked/Unchecked Exceptions

try, catch, finally, throw, throws

Precedence/AssociationRules

Object-orientedProgramming (OOP)

Encapsulation

Inheritance

Polymorphism

Java Virtual Machine (JVM)

Stack and Heap Memory

Garbage Collector

Class Loader

Method Overriding/Overloading

interface, abstract class, casting

118

▪ Suchato, A., 2011, Learning Computer Programming using Java with 101 Examples, Chulalongkorn University.

▪ D. Solis and C. Schrotenboer, 2018, Illustrated C# 7, 5th edition, Apress.

Reference

java programming part 1mcsc.sc.mahidol.ac.th/courses/cps/slides/java.pdf · 3 cpu executes...

Documents