Scope Bean initMethod destroyMethod Value

阳光穿透心脏的1/2处 2023-02-18 09:35 6阅读 0赞

由 Spring进行管理 scope 默认是 一个容器中只有一个bean
    *  (1) Singleton:一个 Spring容器中只有一个Bean的实例，此为 Spring的默认配置，全局容器共享一个实例。
    2) Prototype:每次调用新建一个Bean的实例。
    (3)Request:web项目中，给每一个httprequest新建一个Bean实例。
    (4)Session:Web项目中，给每一个httpsession新建一个Bean实例。
    (5)GlobalSession:这个只在portal应用中有用，给每一个globalhttpsession新建

单例类  和 每次调用 创建一个类

package spring.scope8EL8Value.Scope;
    
    import org.springframework.context.annotation.Scope;
    import org.springframework.stereotype.Service;
    
    /**
     * Created by lovejing on 2020/6/16.
     *
     *  由 Spring进行管理 scope 默认是 一个容器中只有一个bean
     *  (1) Singleton:一个 Spring容器中只有一个Bean的实例，此为 Spring的默认配置，全局容器共享一个实例。
     2) Prototype:每次调用新建一个Bean的实例。
     (3)Request:web项目中，给每一个httprequest新建一个Bean实例。
     (4)Session:Web项目中，给每一个httpsession新建一个Bean实例。
     (5)GlobalSession:这个只在portal应用中有用，给每一个globalhttpsession新建
     实例
     */
    @Service
    @Scope("singleton")
    public class ScopeSingleService {
        String param1;
    }

配置类

package spring.scope8EL8Value.Scope;
    
    import org.springframework.context.annotation.ComponentScan;
    import org.springframework.context.annotation.Configuration;
    
    /**
     * Created by lovejing on 2020/6/16.
     * 声明配置类  配置扫描包
     */
    @Configuration
    @ComponentScan("spring")
    public class ConfigJava {
    
    }

main 测试

package spring.scope8EL8Value.Scope;
    
    import org.springframework.context.annotation.AnnotationConfigApplicationContext;
    
    /**
     * Created by lovejing on 2020/6/16.
     */
    public class MainJava {
        public static void main(String[] args) {
            AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(ConfigJava.class);// 加载容器 指定配置类
            ScopeSingleService singleService = context.getBean(ScopeSingleService.class);
            ScopeSingleService singleService1 = context.getBean(ScopeSingleService.class);
            ScopeProtorypeService scopeProtorypeService = context.getBean(ScopeProtorypeService.class);
            ScopeProtorypeService scopeProtorypeService2 = context.getBean(ScopeProtorypeService.class);
            System.out.println("single注解："+singleService.equals(singleService1));
            System.out.println("Protorype注解："+scopeProtorypeService.equals(scopeProtorypeService2));
        }
    }

运行结果：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Jvc3Nfd2F5_size_16_color_FFFFFF_t_70][]

@Value 使用

package spring.scope8EL8Value.value;
    
    import org.apache.commons.io.IOUtils;
    import org.aspectj.lang.annotation.Before;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.ComponentScan;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.context.annotation.PropertySource;
    import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;
    import org.springframework.core.env.Environment;
    import org.springframework.core.io.Resource;
    
    import java.io.IOException;
    
    /**
     * Created by lovejing on 2020/6/16.
     */
    @Configuration
    @ComponentScan("spring")
    //@PropertySource("classpath:spring/scope8EL8Value/value/test.txt")
    public class ValueConfigJava {
        @Value("注入普通字符串") // 注入普通字符串
        private String name;
    
    //    @Value("#{SystemProperties['os.name']}")// 注入操作系统属性
    //    private String osName;
    
        @Value("#{T(java.lang.Math).random()*333.1}")
        private double number;
    
    //    @Value("classpath:spring/scope8EL8Value/value/test.txt")
    //    private Resource textFile;
    
    //    @Value("${aaa.bb}")
    //    private String param;
        @Value("http://www.baidu.com")
        private Resource resource;
    
        @Autowired
        private Environment environment;
    
        @Bean
        public static PropertySourcesPlaceholderConfigurer getPropertySourcesPlaceholderConfigurer(){
            return  new PropertySourcesPlaceholderConfigurer();
        }
    
        public void outPrint() throws IOException {
            System.out.println(name);
    //        System.out.println(osName);
            System.out.println(number);
    //        System.out.println(IOUtils.toString(textFile.getInputStream()));
    //        System.out.println(param);
            System.out.println(environment.getProperty("aaa.bb"));
            System.out.println(IOUtils.toString(resource.getInputStream()));
    
        }
    }

main 运行：

package spring.scope8EL8Value.value;
    
    import org.springframework.context.annotation.AnnotationConfigApplicationContext;
    
    import java.io.IOException;
    
    /**
     * Created by lovejing on 2020/6/16.
     */
    public class MainJAVA {
        public static void main(String[] args) throws IOException {
            AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(ValueConfigJava.class);
            ValueConfigJava bean = context.getBean(ValueConfigJava.class);
            bean.outPrint();
            context.close();
        }
    }

运行结果：

![20200616232412499.png][]

bean 的初始化和销毁

写一个bean ,随便写两个方法，然后用注解的@Bean 的时候进行关联

package spring.bean;
    
    /**
     * Created by lovejing on 2020/6/16.
     */
    public class ThisIsBean {
        String initS = "";
    
        public String getDestory() {
            return destory;
        }
    
        public String getInitS() {
            return initS;
        }
    
        public void setInitS(String initS) {
            this.initS = initS;
        }
    
        public void setDestory(String destory) {
            this.destory = destory;
        }
    
        String destory = "";
        public String initMethod(){
            System.out.println("bean初始化");
            initS = "初始化"; // 可以利用初始化给一下 变量赋值
            return initS;
        }
        public String destoryMethod(){
            System.out.println("bean destory");
            destory = "destory";
            return destory;
        }
    }

使用@Bean  关联方法

package spring.bean;
    
    import org.springframework.context.annotation.AnnotationConfigApplicationContext;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.ComponentScan;
    import org.springframework.context.annotation.Configuration;
    
    /**
     * Created by lovejing on 2020/6/16.
     */
    @Configuration
    @ComponentScan("spring.bean")
    public class ConfigBean {
        // initMethod = "initMethod",destroyMethod = "destoryMethod"  分别是关联了 bean 对象ThisIsBean 中的两个方法
        @Bean(initMethod = "initMethod",destroyMethod = "destoryMethod")
        ThisIsBean thisIsBean(){
            return  new ThisIsBean();
        }
    
    }

main 运行：

package spring.bean;
    
    import org.springframework.context.annotation.AnnotationConfigApplicationContext;
    
    /**
     * Created by lovejing on 2020/6/16.
     */
    public class javaMain {
        public static void main(String[] args) {
            AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(ConfigBean.class);
            ThisIsBean bean = context.getBean(ThisIsBean.class);
            ThisIsBean thisIsBean = new ThisIsBean();
            String 获取到的容器bean的值 = bean.initS;
            String initS = thisIsBean.getInitS();
            System.out.println("new的值"+initS);
            System.out.println("获取到的容器bean的值"+获取到的容器bean的值);
    
            context.close();
        }
    }

运行结果：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Jvc3Nfd2F5_size_16_color_FFFFFF_t_70 1][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Jvc3Nfd2F5_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200616232219218.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Jvc3Nfd2F5,size_16,color_FFFFFF,t_70
[20200616232412499.png]: https://img-blog.csdnimg.cn/20200616232412499.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Jvc3Nfd2F5_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20200616232856534.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Jvc3Nfd2F5,size_16,color_FFFFFF,t_70