spring （学习记录）通过工厂方法配置bean

男娘i 2022-04-10 06:07 211阅读 0赞

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3Nzc0MTcx_size_16_color_FFFFFF_t_70]

xml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"
    	xmlns:util="http://www.springframework.org/schema/util"
    	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
    	 http://www.springframework.org/schema/util
         http://www.springframework.org/schema/util/spring-util.xsd
    	"
    	>
    	
    	
    	
         
    	<bean id="car1" class="com.beans.factory.StaticCarFactory"
    	factory-method="getCar">
    	 <constructor-arg value="audi"></constructor-arg>
    	</bean>
    	
    	
    
    
         
         <bean id="carFactory" class="com.beans.factory.InstanceCarFactory">
         </bean>
    
         
         
         <bean id="car2" factory-bean="carFactory" factory-method="getCar">
         <constructor-arg value="ford"></constructor-arg>
         </bean>
    </beans>

Car类

package com.beans.factory;
    
    public class Car {
            public String brand;
            public double price;
    		public String getBrand() {
    			return brand;
    		}
    		public Car() {
    			super();
    			// TODO Auto-generated constructor stub
    			System.out.println("Car's constructor....");
    		}
    		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(String brand, double price) {
    			super();
    			this.brand = brand;
    			this.price = price;
    		}
            
    }

StaticCarFactory.java

package com.beans.factory;
    
    import java.util.HashMap;
    import java.util.Map;
    //静态工厂方法：直接调用某一个类的静态方法就可以返回bean的实例
    public class StaticCarFactory {
           
    	private static Map<String, Car> cars=new HashMap<String,Car>();
    	static {
    		cars.put("audi", new Car("audi",3000000));
    		cars.put("ford", new Car("ford",4000000));
    		
    	}
    	//静态工厂方法
    	public static Car getCar(String name) {
    		return cars.get(name);
    	}
    }

InstanceCarFactory.java

package com.beans.factory;
    
    import java.util.HashMap;
    import java.util.Map;
    
    import javax.naming.event.NamespaceChangeListener;
    /*实例工厂方法：实例工厂的方法，即先需要创建工厂本身，再调用工厂实例方法
     * 来 返回bean的实例
     * */
    public class InstanceCarFactory {
            private Map<String, Car> cars=null;
    
    		public InstanceCarFactory() {
    			cars=new HashMap<String,Car>();
    			cars.put("audi", new Car("audi",3000000));
    			cars.put("ford",new Car("ford",4000000));
    			
    		}
    		public Car getCar(String brand) {
    			return cars.get(brand);
    		}
            
    }

运行主类

package com.beans.factory;
    
    import org.omg.CORBA.CTX_RESTRICT_SCOPE;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    
    public class Main {
            public static void main(String[] args) {
    			ApplicationContext ctx=new ClassPathXmlApplicationContext("beans-factory.xml");
    			Car car=(Car) ctx.getBean("car1");
    			System.out.println(car);
    			car = (Car) ctx.getBean("car2");
    			System.out.println(car);
    		}
    }

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3Nzc0MTcx_size_16_color_FFFFFF_t_70 1]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3Nzc0MTcx_size_16_color_FFFFFF_t_70]: /images/20220402/700dab6fded440568fb011988989456f.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3Nzc0MTcx_size_16_color_FFFFFF_t_70 1]: /images/20220402/2f287650d70e4b8495c165f573e1c856.png