版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/u010285684/article/details/79624744
一、组件说明
@Scope:给隱作用域范围是singleton（单例）,prototype（多例），request（单次请求范围内），session（会话范围内有效），在没有指定作用域的时候，bean默认是单例的
二、代码说明
1.单例
package com.guang.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import com.guang.entity.Person;
@Configuration
// @ComponentScan("包路径") 会自动扫描包路径下面的所有@Controller、@Service、@Repository、@Component 的类
// includeFilters 指定包含扫描的内容
// excludeFilters 指定不包含的内容
// @Filter 指定过滤规则，type指定扫描的规则（注解，正则，自定义，ASPECTJ表达式），classes指定的扫描的规则类
@ComponentScan(basePackages = {"com.guang"}
// includeFilters = @Filter(type = FilterType.ANNOTATION, classes = {Controller.class}),
// excludeFilters = @Filter(type = FilterType.ANNOTATION, classes = {Repository.class}),
// includeFilters = @Filter(type = FilterType.CUSTOM, classes = {FilterCustom.class}),
// useDefaultFilters = false
)
public class Myconfig {
/**
* <p>
*
* @Bean 默认的情况下是单例的，要想改变作用域(singleton, prototype, request, session)，只能通过@Scope(value="xxx")
*
* @return Person
* @Title person01
* @author xxx
* @date xxx
* @version xxx
*/
// @Scope(value = "prototype")
@Bean("person")
public Person person01() {
System.out.println("正在创建实例......");
return new Person("aha", 25);
}
}
/**
* 测试@Scope注解
*
* @return void
* @Title scopeTest
* @author xxx
* @date xxx
* @version xxx
*/
@Test
public void scopeTest() {
ac = new AnnotationConfigApplicationContext(Myconfig.class);
System.out.println("容器创建完成......");
Person person = (Person) ac.getBean("person");
System.out.println(person);
Person person1 = (Person) ac.getBean("person");
System.out.println(person1);
System.out.println(person == person1);
}输出结果
从结果可以看出person实体在容器初始化的时候就已经放入spring容器中了
2.多例代码说明
package com.guang.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Scope;
import com.guang.entity.Person;
@Configuration
// @ComponentScan("包路径") 会自动扫描包路径下面的所有@Controller、@Service、@Repository、@Component 的类
// includeFilters 指定包含扫描的内容
// excludeFilters 指定不包含的内容
// @Filter 指定过滤规则，type指定扫描的规则（注解，正则，自定义，ASPECTJ表达式），classes指定的扫描的规则类
@ComponentScan(basePackages = {"com.guang"}
// includeFilters = @Filter(type = FilterType.ANNOTATION, classes = {Controller.class}),
// excludeFilters = @Filter(type = FilterType.ANNOTATION, classes = {Repository.class}),
// includeFilters = @Filter(type = FilterType.CUSTOM, classes = {FilterCustom.class}),
// useDefaultFilters = false
)
public class Myconfig {
/**
* <p>
*
* @Bean 默认的情况下是单例的，要想改变作用域(singleton, prototype, request, session)，只能通过@Scope(value="xxx")
*
* @return Person
* @Title person01
* @author xxx
* @date xxx
* @version xxx
*/
@Scope(value = "prototype")
@Bean("person")
public Person person01() {
System.out.println("正在创建实例......");
return new Person("aha", 25);
}
}
/**
* 测试@Scope注解
*
* @return void
* @Title scopeTest
* @author xxx
* @date xxx
* @version xxx
*/
@Test
public void scopeTest() {
ac = new AnnotationConfigApplicationContext(Myconfig.class);
System.out.println("容器创建完成......");
Person person = (Person) ac.getBean("person");
System.out.println(person);
Person person1 = (Person) ac.getBean("person");
System.out.println(person1);
if (person == person1) {
System.out.println("两个对象相等，说明是单例模式");
} else {
System.out.println("两个对象不相等");
}
}输出结果