Many developers used to write a main function for every class that can be tested separately. When we export it as a jar file, we usually specify a main class for execution of the jar file. Running this jar file is straightforward,

$ java -jar test.jar

But from time to time, some bugs are [...]

This is the 4th part of the Java Programming Cheat Sheet. You can find the first three parts here:

1. OO Concepts

2. Java Syntax

3. Basic I/O

Collection: sometimes called a container, an object that groups multiple elements into a single unit. The Java [...]

This is the third part of the Java programming cheat sheet. You may also interested in the first part OO concepts and second part Syntax.

I/O from Command Line: Java provides two ways, through the standard streams and through the Console standard streams: Java supports three standard streams: standard input (System.in), standard [...]

This is the second part of java programming cheat sheet. You may also interested in the first part OO Concepts and third part Basic I/O.

Primitive Data Types: Java compiler assign a default value for class fields, but not local variables.

Data Type

Sign

Default Value (for fields)

byte [...]

I first learned Java more than 5 years ago. But I switch between different programming languages and sometimes it’s easy to get confused. Recently I decided to refresh my Java knowledge, and this cheat sheet is a note based on my revision. It covers OO (Object Oriented) concepts, Java Syntax, and Basic I/O (Input/Output).

This [...]