Spring 框架Bean的自动装配

Spring IOC可以自动装配Bean。

例子

beans-autowire.xml

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:p="http://www.springframework.org/schema/p"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="address" class="com.spring.test.autowire.Address" p:city="Suzhou" p:street="ShiLu">bean>
    <bean id="car" class="com.spring.test.autowire.Car" p:brand="Audi" p:price="200000">bean>
    <bean id="car1" class="com.spring.test.autowire.Car" p:brand="Fute" p:price="300000">bean>
    
    <bean id="person" class="com.spring.test.autowire.Person" p:name="Kitty" autowire="byName">bean>
beans>

Main.java

package com.spring.test.autowire;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Main {

    @Test
    public void testAutoWire() {
        ApplicationContext context = new ClassPathXmlApplicationContext("beans-autowire.xml");
        Person person = (Person) context.getBean("person");
        System.out.println(person);
    }
}

Address.java

package com.spring.test.autowire;

public class Address {

    private String city;
    private String street;

    public String getCity() {
        return city;
    }
    public void setCity(String city) {
        this.city = city;
    }
    public String getStreet() {
        return street;
    }
    public void setStreet(String street) {
        this.street = street;
    }

    @Override
    public String toString() {
        return "Address [city=" + city + ", street=" + street + "]";
    }
}

Car.java

package com.spring.test.autowire;

public class Car {
    private String brand;
    private double price;

    public String getBrand() {
        return brand;
    }
    public void setBrand(String brand) {
        this.brand = brand;
    }
    public double getPrice() {
        return price;
    }
    public void setPrice(double price) {
        this.price = price;
    }
    @Override
    public String toString() {
        return "Car [brand=" + brand + ", price=" + price + "]";
    }
}

Person.java

package com.spring.test.autowire;

public class Person {
    private String name;
    private Address address;
    private Car car;

    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 Car getCar() {
        return car;
    }
    public void setCar(Car car) {
        this.car = car;
    }

    @Override
    public String toString() {
        return "Person [name=" + name + ", address=" + address + ", car=" + car + "]";
    }
}