The concept notes and annotations common

The concept notes and annotations common

I. Introduction

Annotations can simplify the development process in a complex configuration file, optimized model of the structure, so that the current becomes gradually development model annotation + + reflective design pattern

Second, the concept notes

Annotation concept

     * Notes in the code symbol is a mark, these marks may be symbols of the source code, compile and runtime are read, performing the corresponding functions.

Annation modification range

     * Annotations can be used to modify the code of the package, class, method, constructor, variables and parameters, which information is stored in the Annation (Key: Val) key-value pair. 

 Third, the common comment

@Override: override the parent class method  
@Deprecated: the current code is outdated, but you can continue to use. 
@Test: The current approach to testing methods

 @Override use annotations

public class AnnotationTest {
    /**
     * @Override 重写父类方法
     */

    private String name;
    private int age;

    @Override
    public String toString() {
        return "AnnotationTest{" +
                "name='" + name + '\'' +
                ", age=" + age +
                '}';
    }

 NOTE Using @Deprecated

//Date类中的过时方法

@Deprecated
    public Date(String s) {
        this(parse(s));
    }

NOTE Using @Test

@Test
    public void test() {
        System.out.println("Test Function");
    }