這個課程的參考視訊在youtube。

    主要學到的知識點有：

1. Create new project, choose Java Application.
2. one .jar file/ package(.jar name with the same as package), one package can contains mutiple .java files.
3. Comment mutiple lines by using "/* */"; comment one line by using "//"

/*
*  This is example to comment mutliple lines
 
*/

// This is one line comment

• A class is the template from which objects are created.
• Objects is instances of a class.
• public can be accessed by other class and private can not.
• static means that you can use it without define it first. 
• void mens return nothing, like in C.
• Statements should end with ;