Revision as of 05:22, 29 August 2016

Chapter 1: Intro to Java

Sections:

1.1 Basic computing concepts

1.2 And now, Java

1.3 Program errors

1.4 Procedural decomposition

1.5 Case study: DrawFigs

Note: the first chapter is definitions-heavy.

Section 1.1: Intro to Java

Definitions

Algorithm
Program
Hardware ("Hardware: the part of the computer that you can kick")
Software
Digital
Binary
Program execution
Compiler
Java Virtual Machine (JVM)
Java Runtime Environment (JRE)

Material

Things to cover:

Java class libraries (standard library)
Java programming environment
Java Hello World program
Eclipse editor ("Why can't Java programmers see well?" "Because of the Eclipse.")
Console window/command line

Quotes

1995: Oracle: "Java: A simple, object-oriented, network-savvy, interpreted, robust, secure, architecture-netural, portable, high-performance, multithreaded, dynamic language."

=Life Skills

Life skills track:

Pay attention and FOCUS
RTFM
Follow directions and read carefully
Whether it's your compiler, or your instructor, or your fellow students - pay attention to what's being said
Skill will pay off when you start to compile your Java programs

Section 1.2: Java

Class

Every program, all Java code, lives in a class
Class header
Class methods
Statements
String literals
System.out.println
Escape sequences
print vs println

Complex example: draw figures

ASCII diamond, X, rocket

Code comments, white space, readability:

Comments

Profiles:

James Gosling - Oracle, tech companies, open source vs. enterprise, hackers vs suits

Section 1.3: Syntax Errors

Different types of errors:

Where the errors happen - the normal process - (code) --> (compiler) --> (bytecode)
Errors at compiler level - syntax errors - book lists common syntax errors
Errors at code level - bugs - errors in the logic of the program (wrong idea, or right idea but implemented wrong)

Pofiles:

Grace Hopper

Section 1.4: Procedural Decomposition

Decomposing complexity:

Decomposition concept: split into functions, tasks, subtasks

C is very verb-oriented, action-oriented

Java is very noun-oriented, object-oriented

Procedural programming:

Function-based, action-based programming
How to decompose task of baking a cake
Static methods (help serve function of.......... functions)

Object oriented programming version:

c = new Cake(); c.make()
Encapsulating complexity of the object
Example in book: drawBox, drawTopX, drawBottX

Flow control

How control changes with function calls
Objects: with OOP it becomes more complicated to follow the flow of the program
Procedural programs and interpreted languages: you just start at the top and go from there
Objects: "when is this code actually used?" (have to dive in to see)
Learning to follow program flow control
Flow control allows you to abstract away detail
Example runtime error