1. Chapter One: Introduction
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

2. To understand the activity of programming
Chapter Goals
To understand the activity of programming
To learn about the architecture of computers
To learn about machine code and high level programming languages
To become familiar with your computing environment and your compiler
To compile and run your first Java program
To recognize syntax and logic errors
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

3. Computer savvy (file management, text editing) Problem solving skills
Prerequisites
Computer savvy (file management, text editing)
Problem solving skills
Time management
High school basic math
No prior programming background required
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

4. Computers are programmed to perform tasks
What Is Programming?
Computers are programmed to perform tasks
Different tasks = different programs
Program
Sequence of basic operations executed in succession
Contains instruction sequences for all tasks it can execute
Sophisticated programs require teams of highly skilled programmers and other professionals
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

5. The Anatomy of a Computer
Central processing unit
Chip
Transistors
Storage
Primary storage: Random-access memory (RAM)
Secondary storage: e.g. hard disk
Removable storage devices: e.g.: floppy disks, tapes, CDs
Peripherals
Executes very simple instructions
Executes instructions very rapidly
General purpose device
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

6. The Anatomy of a Computer
Central processing unit
Chip
Transistors
Storage
Primary storage: Random-access memory (RAM)
Secondary storage: e.g. hard disk
Removable storage devices: e.g.: floppy disks, tapes, CDs
Peripherals
Executes very simple instructions
Executes instructions very rapidly
General purpose device
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

7. bj4_01_04 Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

8. Schematic Diagram of a Computer
                                                                    
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

9. The first usable electronic computer
The ENIAC
The first usable electronic computer
designed by John Mauchly and J. Presper Eckert of the University of Pennsylvania
Completed by 1946
Contained about vaccuum tubes in many cabinates
Weighed more than 27 tons was roughly 2.4 m × 0.9 m × 30 m
Consumed 150 kW of power
Vaccuum tubes burned out at the rate of several tubes per day
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

10. Work on the ENIAC was supported by U.S. Navy
Computation of ballistic table give the trajectory of a projectile
Depend on
the wind resistance
initial velocity
atmospheric condition
1950’s the word computer referred to people who did that kind of work
the ENIAC was later used for peaceful purposes such as tabulator of U.S. census data
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

11. The ENIAC Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

12. Translating Human-Readable programs to Machine Code
the processor executes machine instructions
CPU from different vendors have different sets of machine instructions.
Java programs contain machine instructions for a so-called “Java virtual machine” (JVM) that being enable Java applications to run on different CPUs without modification
Java virtual machine is an idealized CPU that is simulated by a program run on the actual CPU
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

13. Machine instructions are encoded as numbers: 21 40 16 100 163 240
Machine Code
Java Virtual Machine (JVM) – a typical sequence of machine instructions is:
Load the contents of memory location 40.
Load the value 100.
If the first value is greater than the second value, continue with the instruction that is stored in memory location 240.
Machine instructions are encoded as numbers:
Compiler translates high-level language to machine code
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

14. Java Virtual Machine (JVM)
fetch sequence of numbers
21 40
decode them
execute the associated sequence of commands
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

15. Communicate the command sequence to the computer
The most direct method is to place the actual numbers into computer memory
It is tedious and error-prone to look up the numeric codes for thousands command and manually place the code into memory.
Computer are good at automating tedious and error-prone activities.
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

16. High-level Programming Language
Began to appear in the mid-1950s
Programmer expresses the idea behind the task that needs to be performed
Compiler translates the high-level description into machine instructions for a particular processor
For example
Java instruction
If (intRate > 100)
System.out.println(“Interest rate error”);
Translate into …
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

17. The Java Programming Language
Originaly named Oak
Developed as a part of the Green project at the Sun Microsystems for use in consumer devices in 1991.
Designed by James Gosling, Patrick Naughton and others in 1994.
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

18. The Java Programming Language
Simple
Safe
Platform-independent ("write once, run anywhere")
Rich library (packages)
Designed for the internet
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

19. that contains Java code, the code automaticlly running.
Applets on a Web Page
Visit web page
that contains Java code,
the code automaticlly running.
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

20. Java Versions Java was revised and extended many times Version Year
Important New Features
JDK 1.0
1996
JDK 1.1
1997
Inner classes
J2SE 1.2
1998
Swing, Collections
J2SE 1.3
2000
Performance enhancements
J2SE 1.4
2002
Assertions, XML
J2SE 5
2004
Generic classes, enhanced for loop, auto-boxing, enumerations
JAVA SE 6
2006
Library improvements
JAVA SE 7
2011
JAVA SE 8
2014
JAVA SE 9
2017
JAVA SE 10
2018
Small language changes and library improvments
Java was revised and extended many times
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

21. You cannot hope to learn all of Java in one term
Java library
You cannot hope to learn all of Java in one term
Java itself is relative simple but Java has a vast library with support for
Graphics
User interface design
Cryptography
Networking
Sound
Database storage
Many other purposes
Expert Java programmers just use some parts that they need to particular projects
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

22. An Integrated Development Environment
An Integrated Development Environment
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

23. ch01/hello/HelloPrinter.java Output: Hello, World!
1: public class HelloPrinter
2: {
3: public static void main(String[] args)
4: {
5: // Display a greeting in the console window 6:
7: System.out.println("Hello, World!");
8: }
9: }
Output:
Hello, World!
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

24. HelloPrinter in an IDE Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

25. Classes are a fundamental concept in Java.
HelloPrinter.java
HelloPrinter.java
Start a new class
1: public class HelloPrinter
2: {
3: public static void main(String[] args)
4: {
5: // Display a greeting in the console window 6:
7: System.out.println("Hello, World!");
8: }
9: }
comment
Output:
Hello, World!
Classes are a fundamental concept in Java.
In Java, every program consists of one or more classes
The word “public” denotes that
the class is usable by the public
In Java, every source file can contain at one public class
and the name of the public class must match
the name of the file containing the class
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

26. main method The above construction declares a method called main
public static void main(String[] args) { …. }
The above construction declares a method called main
A method contains a collection of programming instructions
Every Java application must have a main method.
Most Java programs contain other methods beside main.
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

27. The above construction declares a method called main
ch01/hello/HelloPrinter.java
public static void main(String[] args) { …. }
The above construction declares a method called main
A method contains a collection of programming instructions
Every Java application must have a main method.
Most Java programs contain other methods beside main.
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

28. HelloPrinter.java Body of main method
Start a new class
1: public class HelloPrinter
2: {
3: public static void main(String[] args)
4: {
5: // Display a greeting in the console window 6:
7: System.out.println("Hello, World!");
8: }
9: }
Body of
main
method
Statement inside the curly brackets are executed one by one.
Each statement ends in a semicolon(;)
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

29. System.out
1: public class HelloPrinter
2: {
3: public static void main(String[] args)
4: {
5: // Display a greeting in the console window 6:
7: System.out.println("Hello, World!");
8: }
9: }
The console window is represented in Java by an object called System.out.
An object is an entity that you manipulate in your program
In Java, each object belongs to a class
The class declares methods that specify what you can do with the objects
System.out object belongs to PrintStream class
PrintStream class has a method called println for printing a line of text.
called Syste.out
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

30. A Simple Program public class ClassName
public static void main(String[] args)
// comment
Method call
System class
System.out object
println method
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

31. To invoke a method of an object and supply any additional parameters.
Syntax 1.1 Method Call
object.methodName(parameters)
Example:
System.out.println("Hello, Dave!");
Purpose:
To invoke a method of an object and supply any additional parameters.
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

32. bj4_syn_01_01 Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

33. Answer: System.out.println("Hello,"); System.out.println("World!");
Self Check
How would you modify the HelloPrinter program to print the words "Hello," and "World!" on two lines?
Answer: System.out.println("Hello,"); System.out.println("World!");
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

34. Self Check 1.13
Would the program continue to work if you omitted the line starting with //?
Answer: Yes – the line starting with // is a comment, intended for human readers. The compiler ignores comments.
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

35. Answer: The printout is
Self Check 1.14
What does the following set of statements print? System.out.print("My lucky number is"); System.out.println( );
Answer: The printout is
My lucky number is12
It would be a good idea to add a space after the is.
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

36. Detected by the compiler Logic errors System.out.print("Hell");
Syntax errors
System.ouch.print(". . .");
System.out.print("Hello);
Detected by the compiler
Logic errors
System.out.print("Hell");
Detected (hopefully) through testing
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

37. Self Check 1.15
Suppose you omit the // characters from the HelloPrinter.java program but not the remainder of the comment. Will you get a compile-time error or a run-time error?
Answer: A compile-time error. The compiler will not know what to do with the word Display.
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

38. The Compilation Process
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

39. Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

40. bytecodes bytecodes Class loader Execution engine Java virtual machine
program
class files
API
class files
bytecodes
bytecodes
Class loader
Execution
engine
Java virtual machine
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

41. The Edit-Compile-Test Loop  
The Edit-Compile-Test Loop
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

42. Source files and Class files
The source file of a Java class is stored in a file: ClassName.java Java source files are essentially text files and can be opened in any text editor
The compiled file of a Java class is stored in a file: ClassName.class Java class files are binary files (not human-readable).
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

43. Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

44. Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.

45. Install Java and Eclipse Eclipse IDE:
Homework
Obtain a Course Book
Install Java and Eclipse
Eclipse IDE:
Read the following eclipse tutorials
Help -> Help contents ->
Workbench User Guide
Basic tutorial thru Deleting Resources
Java Development User Guide
Basic tutorial thru Running Your Program
Don’t worry about understanding details of JUnit sample project
Big Java by Cay Horstmann
Copyright © 2008 by John Wiley & Sons. All rights reserved.