SpringIOC_01 根据bean的类型从IOC容器中获取bean的实例

客官°小女子只卖身不卖艺 2023-06-18 11:55 17阅读 0赞

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Person,java：

import java.util.List;
    import java.util.Map;
    import java.util.Properties;
    
    public class Person { 
    	
    	//基本类型直接使用
    	//<property name="lastName" value="张三"></property>它会自动进行类型转换
    	private String lastName;
    	private Integer age;
    	private String gender;
    	private String email;
    	
    	public Person(String lastName, Integer age, String gender) { 
    		super();
    		this.lastName = lastName;
    		this.age = age;
    		this.gender = gender;
    		System.out.println("三个参数的构造器...age");
    	}
    	public Person(String lastName, String email, String gender) { 
    		super();
    		this.lastName = lastName;
    		this.gender = gender;
    		this.email = email;
    		System.out.println("三个参数的构造器...email");
    	}
    	public Person(String lastName, Integer age, String gender, String email) { 
    		super();
    		this.lastName = lastName;
    		this.age = age;
    		this.gender = gender;
    		this.email = email;
    		System.out.println("有参构造器...");
    	}
    	public Person() { 
    		super();
    		// TODO Auto-generated constructor stub
    		System.out.println("person创建了...");
    	}
    	public String getLastName() { 
    		return lastName;
    	}
    	public void setLastName(String lastName) { 
    		this.lastName = lastName;
    		System.out.println("setLastName..."+lastName);
    	}
    	public Integer getAge() { 
    		return age;
    	}
    	public void setAge(Integer age) { 
    		this.age = age;
    	}
    	public String getGender() { 
    		return gender;
    	}
    	public void setGender(String gender) { 
    		this.gender = gender;
    	}
    	public String getEmail() { 
    		return email;
    	}
    	public void setEmail(String email) { 
    		this.email = email;
    	}
    	@Override
    	public String toString() { 
    		return "Person [lastName=" + lastName + ", age=" + age + ", gender="
    				+ gender + ", email=" + email  + "]";
    	}
    }

ioc.xml：

<?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: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="person01" class="com.guigu.bean.Person">
    		
    		<property name="lastName" value="张三"></property>
    		<property name="age" value="18"></property>
    		<property name="email" value="zhangsan@qq.com"></property>
    		<property name="gender" value="男"></property>
    	</bean>
    	
    	<bean id="person02" class="com.guigu.bean.Person">
    		<property name="lastName" value="小花"></property>
    	</bean>
    	
    	<bean id="person03" class="com.guigu.bean.Person">
    		
    		<constructor-arg name="lastName" value="小明"></constructor-arg>
    		<constructor-arg name="age" value="17"></constructor-arg>
    		<constructor-arg name="email" value="4887845@qq.com"></constructor-arg>
    		<constructor-arg name="gender" value="男"></constructor-arg>
    	</bean>
    	
    	<bean id="person04" class="com.guigu.bean.Person">
    		
    		
    		
    		<constructor-arg value="大卫" index="0"></constructor-arg>
    		<constructor-arg value="18" index="1"></constructor-arg>
    		<constructor-arg value="4564@qq.com" index="3"></constructor-arg>
    		<constructor-arg value="男" index="2"></constructor-arg>
    	</bean>
    	
    	<bean id="person05" class="com.guigu.bean.Person">
    		
    		
    		
    		<constructor-arg value="老王"></constructor-arg>
    		<constructor-arg value="18" index="1" type="java.lang.Integer"></constructor-arg>
    		<constructor-arg value="男"></constructor-arg>
    	</bean>
    	
    	
    	
    	
    	
    	
    	 	<bean id="person06" class="com.guigu.bean.Person" p:age="18" p:email="xiaoming@qq.com" p:lastName="哈哈" p:gender="男">
    	 	</bean>
    
    </beans>

IOCTest.java：

import static org.junit.Assert.*;
    
    import org.junit.Test;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    
    public class IOCTest { 
    
    	private ApplicationContext ioc=new ClassPathXmlApplicationContext("ioc.xml");
    	
    	/** * 实验2：根据bean的类型从IOC容器中获取bean的实例 * 如果ioc容器中这个类型的bean有多个，那么用第一种方式查找就会报错。 * */
    	@Test
    	public void test02(){ 
    		//Person bean=ioc.getBean(Person.class);
    		//System.out.println(bean);
    		
    		//还可以这样：
    		Person bean2=ioc.getBean("person02",Person.class);
    		System.out.println(bean2);
    		
    		Object bean3=ioc.getBean("person03");
    		System.out.println(bean3);
    		
    		Object bean4=ioc.getBean("person04");
    		System.out.println(bean4);
    	}
    	
    	/** * 从容器中拿到这个组件 */
    	@Test
    	public void test01() { 		
    		//创建对象是容器做的
    		Person bean=(Person)ioc.getBean("person01");
    		
    		System.out.println(bean);
    	}
    
    }