Java 3rd grade measures Q1 Past question point summary

Self-learning notes Knowledge problem summary

What is Java

--Object-oriented programming language --Compiled type

Variables that can be handled are ...

① "Basic data type" ② "Reference type"

Error checking

--Performed at both "compile time" and "run time"

java command

--The program to be executed requires a "main method" --java programs can be compiled

javac command

--For compilation

「.java」 --java source file extension --Comment description OK --The statement delimiter is "; (semicolon)"

「.class」 --Class file extension --Can be run on another Java platform without compiling

Run

--Execution starts from main method --"Runtime library" "JVM (Java Virtual Machine)" is required

JRE（Java Runtime Environment) --Includes everything you need to run Java programs, except the compiler (Also virtual machines)

Garbage collection

--Ability to release memory areas that are no longer needed