Introduction to Java(1) - CPPT+opy.Jpptx

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1. Introduction to Java Introduction to Computers and Computer Programming

2. Computer Program: Computer Programming Process: Programming Languages: 1.Assembly Language 2.A high-level language History of Programming Languages: Assembler, Compiler, Linker, Loader, Interpreter: Computer Components:

3. History of Programming Languages: (only major languages are listed) 1951 - Assembly Language 1954 - FORTRAN 1958 - LISP 1958 - ALGOL 1959 - COBOL 1964 - BASIC 1964 - PL/I 1970 - Pascal 1972 - C 1978 - SQL (query language) 1980 - C++ 1984 - MATLAB 1990 - Python 1993 - R 1995 - Java 1995 - PHP 2002 - Scratch

4. History and Structure of Java Java is an object-oriented programming language. Java was developed by James Gosling and colleagues at Sun Microsystems in the early 1990s. It was developed to provide a platformindependent programming language. The first public implementation was Java 1.0 in 1995. It made the promise of "Write Once, Run Anywhere", with free runtimes on popular platforms.

5. Structure of Java: Java programs consists of pieces called classes. Objects are instances of classes. From the same class, many objects can be created. An objectoriented program may contain many objects from various classes. Classes contain attributes and methods. Attributes contain data of object. Methods perform actions related with objects.

6. Java has rich collections of existing classes in the Java Class Libraries which are also known as the Java API's (Application Programming Interfaces). To write Java programs, one has to learn: a) the Java language itself (the syntax, the constructs), b) the classes in the Java Class Libraries, c) to write new classes.

7. Java programs go through five phases: 1. Edit: create Java program using an editor and store on disk in a file ending with .java. 2. Compile: bytecodes are created and stored on disk in a file ending with .class. 3. Load: bytecodes are taken from the disk and stored in the memory. 4. Verify: check that all bytecodes are valid, and ensure that the bytecode does not violate Java's security restrictions. 5. Execute: JRE (Java Runtime Engine) reads bytecodes, translates them into instructions that the computer can understand and runs these machine instructions .

8. The Java Development Kit (JDK) 1.Java Runtime Environment (JRE) 2.An interpreter/loader(java) 3.A compiler (javac) 4.An archiver (jar) 5.A documentation generator (javadoc) and other tools needed in Java development JDK can be downloaded from https://www.oracle.com/technetwork/java/javase/downloads/index.html.