01 intro tousingjava
- 1. Welcome To Problem Solving with OOP and Java
- 2. Who Should Learn Java? Have you done some programming? Do you want to learn Java? Do you prefer stimulating dinner conversations over coffee to dry, dull, technical lectures? Do you need this course to graduate?
- 3. Java? © PIC 2012
- 5. What Is A Computer? A computer is something that takes in information (input), processes it according to a set of instructions (program), and produces a result (output). Computers communicate through a binary alphabet. The letters in this alphabet are ‘0’ and ‘1’. Everything else is made out of these ‘letters’ which are called bits. Bits are represented in a computer by electrical signals: low voltage would mean a ‘0’ and higher voltage a ‘1’. Eight bits gathered together form one byte. IDC3931 © PIC
- 6. What Is JAVA? Java is a free, open-source, Object Oriented Programming (OOP) language – everything is contained inside classes and objects. Java isportable – it can run on any machine with a Java Virtual Machine (JVM) installed. No matter what computer you have, you can write the same Java programs.
- 7. How WEuse Java V i r t u a Java l Sourc e bytecod M Code e a Compiler c h i n e s
- 8. How WEuse Java Virtual Machines Source Code Java bytecode Compiler
- 9. Code Structure in Java Collection of Java files source contains many code classes class file A class method aclass.java 1 statement contains many methods and variables method public class aclass{ 2 statement public void statement method() { } }
- 10. What goes in the source file? A source file (with the .java extension) holds one class definition. The class represents a piece of your program, public class Bicycle { although a very tiny application might need just a single class. The class must go within a pair of curly braces The source file MUST have the same name as the class. For example, the Bicycle class must be stored in the Bicycle.javafile. } A class is the blueprint from which individual objects are created. clas
- 11. What goes in a class? A class has one or more methods. In the Bicycle class, the pedal method will hold instructions for how the Bicycle public class Bicycle{ should pedal. Your methods must be void pedal( ) { declared inside a class (in other words, within the curly braces of the class). } A bicycle might have some } methods such as: speedup(), break(), gear(), directi on()… metho
- 12. What goes in a method? Within the curly braces public class Dog { Bicycle{ void bark ( )) {{ pedal( of a method, write your instructions for statement1; how that method should be performed. statement1; statement2; Method code is basically a set of statement2; statement3; statements, and for now you can think statement3; of a function or procedure. } } } statemen
- 13. One Blueprint Can Be Used To Help Build Different Objects Shape rotate ( ) playSound () This is called inheritance Squar Circle Amoeba e Triangl e
- 14. EVERYTHING is made from OBJECTS Object This is the Object class from which ALL other equals() objects are created. getClass() hashCode() toString() Shape rotate() playSound() Circle doSomething()
- 15. What You Will Get Out Of Learning and Using Java! Build your programming skills and confidence. A thorough understanding of Object Oriented Programming. Learn a language that can be run on any platform. Learn how to work and program in groups. Develop Graphical User Interfaces.
- 16. Where To Start Setup Eclipse Classic Write your first Java program If you can, bring your laptops to class every lecture!