Java Learning---3. Object oriented

1. Method overloads: Overload (), same as method names, but with different parameters. Construction methods can also be overloaded.

In-memory layouts

2.this Keyword: This is a variable, is a reference to the current object, this is pointing to himself.

You can handle the case where the name of a member variable and parameter in a method.

3.static keyword: A common variable for a class, initialized for the first time, with only one copy. Allocated in the data area.

No matter the new object instance, it has only one copy. Any object instance can access a static object and access the same piece of memory. (string constants are also in the data area)

The static method of the static declaration does not pass a reference to the object to it when the method is called, so the non-static member is inaccessible in the static method.

4. Package

Resolves a naming conflict problem with classes, providing a tired multi-class namespace.

To define a class:

Package COM.BJSXT;

public class cat{}

Reference class:

Import Com.bjsxt.Cat;

The parent directory of the topmost package of the class file must be located under Classpath. Executes a class to write all-inclusive names.

Package your own class into a jar package: Navigate to the top-level file of the package: JAR-CVF Xx.jar * *

* * Pack all the files into a jar package

Java Learning---3. Object oriented