1、通过bean标签的autowire属性可以实现bean属性的自动装配。

　　创建一个新的Spring配置文件beans-autowire.xml，这里我们配置了3个bean，Address、Car、People，其中People自动装配了另外两个bean，使用的是bean标签的autowire属性，这个例子里如果将car改为car2打印出来的Person bean 的Car属性为null，即byName根据bean的setter风格进行自动装配有就装没有就不装。而使用byType的话如果配置有两个类型相同的bean就会报错。

2、Address.java、Car.java、People.java、Main.java

Address.java

package com.broadtext.beans.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.broadtext.beans.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 + "]";    }    public Car() {        System.out.println("car`s construstor");    }}

People.java

package com.broadtext.beans.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 + "]";    }}

Main.java

package com.broadtext.beans.autowire;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class Main {    /**     * 
Description: 测试bean的自动装配
     */    public static void main(String[] args) {        ApplicationContext ctx = new ClassPathXmlApplicationContext("beans-autowire.xml");        Person person = (Person) ctx.getBean("person");        System.out.println(person);    }}