Static code blocks, construction code blocks, execution of constructors

1  Public classSTR {2 3     Static {4System.out.println ("Static{1}");5     }6     Static {7System.out.println ("Static{2}");8     }9     {TenSystem.out.println ("{}"); One     } A  - Str () { -System.out.println ("Str ()"); the     } -  -      Public Static voidMain (string[] args) { -         NewStr (); +         NewStr (); -     } +}

Output Result:

Static{1}
STATIC{2}
{}
STR ()
{}
STR ()

Conclusion:

1. Static code blocks are executed sequentially and executed once (class loading is performed)

2. Constructs a code block, executes each time the new object is executed, and executes before the constructor

3. Execute the constructor

Understand:

Static code blocks are static, owned by the class, executed when the class is loaded, and construction blocks are non-static, owned by the object, and executed when the object is constructed.

Static code blocks, construction code blocks, execution of constructors