通過FactoryMethod創建對象示例

factory-bean： 指定使用哪個工程實例，實例工廠，非靜態方法創建bean
factory-method：指定使用哪個工廠實例的方法。靜態工廠，靜態方法創建bean
判斷的依據是 創建bean的方法是否存在 static 修飾符。
具體code 如下：

package com.gientech.factoryMethod;

public class Person {

    private int id;
    private String name;
    private int age;
    private String gender;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    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;
    }

    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }

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

創建靜態方法

package com.gientech.factoryMethod;

public class PersonStaticFactory {

    public static Person getPerson(String name){
        Person person = new Person();
        person.setId(1);
        person.setName(name);
        return person;
    }
}

package com.gientech.factoryMethod;

public class PersonInstanceFactory {

    public Person getPerson(String name){
        Person person = new Person();
        person.setId(2);
        person.setName(name);
        return person;

    }
}

創建配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <!-- factory-method : 靜態工廠， 指定使用哪個工廠實例的方法 -->
    <bean id="person" class="com.gientech.factoryMethod.PersonStaticFactory" factory-method="getPerson">
        <constructor-arg value="zhangsan"></constructor-arg>
    </bean>

    <!-- factory-bean : 實例工廠，指定使用哪個工程實例， -->
    <bean id="personInstanceFactory" class="com.gientech.factoryMethod.PersonInstanceFactory"></bean>
    <bean id="person2" class="com.gientech.factoryMethod.Person" factory-bean="personInstanceFactory" factory-method="getPerson">
        <constructor-arg value="lisi"></constructor-arg>
    </bean>
</beans>

創建測試類

package com.gientech.factoryMethod;

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

public class FactoryMethodTest {
    public static void main(String[] args) {
        ApplicationContext ac = new ClassPathXmlApplicationContext("factoryMethod.xml");
        Person person = ac.getBean("person", Person.class);
        System.out.println(person);
        Person person2 = ac.getBean("person2", Person.class);
        System.out.println(person2);
    }
}

運行結果如下：

factoryMethod 執行流程

nstantiateUsingFactoryMethod方法執行流程圖如下：