一、@PropertySource:用于加载指定的配置文件
比如我们在resource下新建一个person.properties
person.username=李四 person.age=12 person.email=zhangsan@qq.com person.maps.k1=v1 person.maps.k2=v2 person.lists=a,b,c person.dog.name=tom person.dog.age=2
在person.java中
package com.gong.springboot.bean; import org.springframework.beans.factory.annotation.Value; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.context.annotation.PropertySource; import org.springframework.stereotype.Component; import java.util.List; import java.util.Map; //将配置文件中的属性映射到组件中 //prefix:表示配置文件中的哪个下面的属性进行一一映射 @Component @ConfigurationProperties(prefix="person") @PropertySource(value={"classpath:person.properties"}) public class Person { /**<bean clas="Person"> * <property name="username" value="字面量/${key}从环境变量中获取值/#{}spel"></property> * </bean> * */ //@Value("${person.username}") private String username; //@Value("#{11*2}") private Integer age; //@Value("test@qq.com") private String email; private Map<String,Object> maps; private List<Object> lists; private Dog dog; public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public Integer getAge() { return age; } public void setAge(Integer age) { this.age = age; } public String getEmail() { return email; } public void setEmail(String email) { this.email = email; } public Map<String, Object> getMaps() { return maps; } public void setMaps(Map<String, Object> maps) { this.maps = maps; } public List<Object> getLists() { return lists; } public void setLists(List<Object> lists) { this.lists = lists; } public Dog getDog() { return dog; } public void setDog(Dog dog) { this.dog = dog; } @Override public String toString() { return "Person{" + "username='" + username + '\'' + ", age=" + age + ", email='" + email + '\'' + ", maps=" + maps + ", lists=" + lists + ", dog=" + dog + '}'; } }
注意:@ConfigurationProperties(prefix="person")不要注释掉。同时主配置文件中不能有person.properties相同的配置,否则自己定义的配置就会失效。进行测试:
Person{username='李四', age=12, email='zhangsan@qq.com', maps={k2=v2, k1=v1}, lists=[a, b, c], dog=Dog{name='tom', age=2}}
二、@ImportResource:导入spring的配置文件,让配置文件的内容生效
在com.gong.springboot下新建一个service包,在该包下新建,HelloWorldService.java
package com.gong.springboot.Service; public class HelloWorldService { }
在resources文件加下新建beans.xml。将HelloWorldService注入到IOC容器中
<?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"> <bean id="helloWorldService" class="com.gong.springboot.Service.HelloWorldService"></bean> </beans>
在主配置类中:
package com.gong.springboot; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.context.annotation.ImportResource; @ImportResource(locations = {"classpath:beans.xml"}) @SpringBootApplication public class Myspringboot2Application { public static void main(String[] args) { SpringApplication.run(Myspringboot2Application.class, args); } }
在测试文件中:
package com.gong.springboot; import com.gong.springboot.Service.HelloWorldService; import com.gong.springboot.bean.Person; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.test.context.SpringBootTest; import org.springframework.context.ApplicationContext; import org.springframework.test.context.junit4.SpringRunner; @RunWith(SpringRunner.class) @SpringBootTest public class Myspringboot2ApplicationTests { @Autowired Person person; @Autowired ApplicationContext ioc; @Test public void contextLoads() { System.out.println(person); } @Test public void testService(){ Boolean b = ioc.containsBean("helloWorldService"); System.out.println(b); } }
运行测试:在控制台可以看到输出true。如果不在主配置类中使用ImportResource注解标识位置,则输出的为false。
三、springboot推荐给容器中添加组件的方式:使用全注解的方式
在com.gong.springboot下新建一个config包,在该包下新建MyAppConfig.java
package com.gong.springboot.config; import com.gong.springboot.Service.HelloWorldService; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; //指明当前类是一个配置类,替代了之前的spring配置文件,也就是beans.xml @Configuration public class MyAppConfig { //Bean注解:将方法的返回值添加到容器中,组件默认的id就是方法名,也就是helloWorldService @Bean public HelloWorldService helloWorldService(){ return new HelloWorldService(); } }
注释掉主配置类中的@ImportResource再进行测试:在控制台还是可以输出true。
来源:https://www.cnblogs.com/xiximayou/p/12246678.html