目录
1、首先创建一个maven项目引入spring依赖
2、新建一个person.java 实体类
3、新建配置类 TestBeanConfig.java
4、resources 创建配置文件
5、新建测试类TestBean.java 具体展示注解方式和配置方式的示例
今天给大家介绍一下Spring中Bean注解的用法,后续的文章给大家介绍Sping其他注解用法，希望对大家日常工作能有所帮助！
1、首先创建一个maven项目引入spring依赖
<dependencies><!-- https://mvnrepository.com/artifact/org.springframework/spring-context --><dependency><groupId>org.springframework</groupId><artifactId>spring-context</artifactId><version>5.3.9</version></dependency>
</dependencies>2、新建一个person.java 实体类
package com.spring.bean;public class Person {private String name;private Integer age;private String address;public Person(String name, Integer age, String address) {this.name = name;this.age = age;this.address = address;}public Person() {}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}public String getAddress() {return address;}public void setAddress(String address) {this.address = address;}@Overridepublic String toString() {return "Person{" +"name='" + name + '\'' +", age='" + age + '\'' +", address='" + address + '\'' +'}';}
}3、新建配置类 TestBeanConfig.java
package com.spring.config;import com.spring.bean.Person;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;@Configuration
public class TestBeanConfig {/*@Bean作用是注册一个Bean，类型为返回值的类型，默认是使用方法名作为id，可以自己定义* value 可以自定义id，默认和方法名一致* */@Bean(value = "person1")public Person person() {return new Person("小王", 35, "北京");}
}4、resources 创建配置文件
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd"><context:component-scan base-package="java"></context:component-scan><bean id="person" class="com.spring.bean.Person"><property name="name" value="小明"></property><property name="age" value="30"></property><property name="address" value="苏州"></property></bean>
</beans>5、新建测试类TestBean.java 具体展示注解方式和配置方式的示例
package com.spring.test;import com.spring.bean.Person;
import com.spring.config.TestBeanConfig;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;public class TestBean {public static void main(String[] args) {//配置文件方式ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext("person.xml");Person bean = (Person) applicationContext.getBean("person");System.out.println("配置方式:");System.out.println(bean);// 注解方式 AnnotationConfigApplicationContext 注解的方式获取spring容器AnnotationConfigApplicationContext annotationContext = new AnnotationConfigApplicationContext(TestBeanConfig.class);Person annotationPerson = (Person) annotationContext.getBean("person1");System.out.println("注解方式:");System.out.println(annotationPerson);// 用来获取Spring容器中指定类型的所有JavaBean的名称String[] beanNamesForType = annotationContext.getBeanNamesForType(Person.class);for (String item : beanNamesForType) {System.out.println(item);}}}6、运行效果：
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