1.依赖注入（DI）

• 依赖注入（Dependency Injection,DI）。
• 依赖 : 指Bean对象的创建依赖于容器 . Bean对象的依赖资源 .
• 注入 : 指Bean对象所依赖的资源 , 由容器来设置和装配 .

1.1 构造器注入

1.2 Set方式注入（重点）

依赖注入：set注入

依赖：bean对象的创建依赖于容器

注入：bean对象中所有的属性，由容器来注入

普通值注入，基于set注入

环境搭建

Address类

package com.zhang.pojo;

public class Address {
    private String address;

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    @Override
    public String toString() {
        return "Address{" +
                "address='" + address + '\'' +
                '}';
    }
}

Student类

package com.zhang.pojo;

import java.util.*;

public class Student {
    private String name;
    private Address address;
    private String[] books;
    private List hobbys;
    private Map card;
    private Set game;
    private String wife;
    private Properties info;

    @Override
    public String toString() {
        return "Student{" +
                "name='" + name + '\'' +
                ", address=" + address +
                ", books=" + Arrays.toString(books) +
                ", hobbys=" + hobbys +
                ", card=" + card +
                ", game=" + game +
                ", wife='" + wife + '\'' +
                ", info=" + info +
                '}';
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Address getAddress() {
        return address;
    }

    public void setAddress(Address address) {
        this.address = address;
    }

    public String[] getBooks() {
        return books;
    }

    public void setBooks(String[] books) {
        this.books = books;
    }

    public List getHobbys() {
        return hobbys;
    }

    public void setHobbys(List hobbys) {
        this.hobbys = hobbys;
    }

    public Map getCard() {
        return card;
    }

    public void setCard(Map card) {
        this.card = card;
    }

    public Set getGame() {
        return game;
    }

    public void setGame(Set game) {
        this.game = game;
    }

    public String getWife() {
        return wife;
    }

    public void setWife(String wife) {
        this.wife = wife;
    }

    public Properties getInfo() {
        return info;
    }

    public void setInfo(Properties info) {
        this.info = info;
    }
}

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>

    
        
    
    

    

1.2.1 常量注入

1.2.2 数组注入

        
        
            
                红楼梦
                西游记
                水浒传
            
        

1.2.3 列表注入

        
        
            
                听歌
                看电影
                敲代码
            
        

1.2.4 map注入

1.2.5 set注入

        
        
            
                LOL
                COC
                BOB
            
        

1.2.6 null注入

        
//方式1
        //方式二
            
        

1.2.7 properties注入

        
        
            
                com.jdbc.cj.JDBC
                localhost:3306
                root
                123456
            
        

1.2.8 bean注入（引用）

完善注入信息

1.3 拓展方式注入

p命名和c命名不能直接使用，需要在头部导入xml约束

xmlns:p="http://www.springframework.org/schema/p"
xmlns:c="http://www.springframework.org/schema/c"

package com.zhang.pojo;

public class User {
    private String name;
    private int age;

    public User() {
    }

    public User(String name, int age) {
        this.name = name;
        this.age = age;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}

p命名注入 property

c命名空间注入 constructor

注意点：p命名和c命名不能直接使用，需要导入xml约束