201671010116.2016-2017-3 Java Programming

How 1.Java works: Java compiles the program into bytecode, and bytecode can be interpreted on any system that provides a Java virtual machine.

Source file: File name. java→ Bytecode file: file name. Class→java Virtual Machine Support program run

2.Java Program Common statements:

(1) public class: Common classes;

(2) System.out.println (): To achieve the output of a sentence;

The Basic program unit in 3.Java is a class, and there should be a public class in each program. The name of the class should conform to the naming convention and be compliant with professional specifications.

4. Each program must have an application main class, which mainly contains the public static void main (String args[]) this method. Each program can have only one main method.

The Process Control statement in 5.Java is the same as the C language.

6.Java is divided into three systems: Javase (JAVA2 Platform standard Edition,java platform), Java EE (Java 2 platform,enterprise Edition,java Platform Enterprise Edition), Javame (Java 2 Platform Micro Edition,java Platform mini version).

7.The Java language does not use pointers, not goto statements.

Eight basic data types for 8.Java

Integer: Short 2 byte int 4 bytes long 8 bytes byte 2 bytes

Float type: Float 4 bytes Double 8 bytes

Character type: Char 2 bytes

Boolean: Boolean this is dependent on the compilation environment

The 9.Java language consists mainly of the following five elements: identifiers, keywords, literals, operators, and separators. These five kinds of elements have different grammatical meanings and constituent rules, they cooperate with each other and accomplish the semantic expression of the Java language together.

-------Li Na

201671010116.2016-2017-3 Java Programming