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关于spring:java开发两年连Spring中bean的装配都不知道你怎么涨薪啊

jiezi

Spring

1.1.1.1 创立一个 bean

package com.zt.spring;

public class MyBean {

    private String userName;

    private Integer userAge;

}

1.1.1.2 配置 Config 配置 bean

package com.zt.spring;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MyBeanConfig {
     // 和 xml 中配置文件的 bean 的标签是一样的
    @Bean(name = "beanName")
    public MyBean createBean(){return new MyBean();
    }
}

1.1.1.3 配置 bean 单例还是多例的 

package com.zt.spring;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Scope;

@Configuration
public class MyBeanConfig {@Bean(name = "beanName")
    // 默认值是多例的  xml 的形式能够在 bean 的标签下面  设置这个参数
    @Scope("prototype")  
    public MyBean createBean(){return new MyBean();
    }

}

1.1.1.4 获取上文，获取 bean

package com.zt.spring;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class App {public static void main(String[] args) {
        // 获取上下文
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(MyBeanConfig.class);
        // 通过 bean 的那么获取 bean
        System.out.println(context.getBean("beanName"));
        // 获取 bean 的 class 文件获取
        System.out.println(context.getBean(MyBean.class));
        context.close();}
}

1.1.2 通过 FactoryBean 实现 bena 的拆卸

1.1.2.1 创立一个 bean

package com.zt.spring;

public class Car {}

1.1.2.2 配置 Config 配置 bean

package com.zt.spring;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MyBeanConfig {

    @Bean
    public CarFactoryBean createRunnableFactoryBean() {return new CarFactoryBean();
    }

}

1.1.2.3 配置 FactoryBean 生产 bean

package com.zt.spring;

import org.springframework.beans.factory.FactoryBean;

public class CarFactoryBean implements FactoryBean<Car> {

    // 获取到对应的实体
    @Override
    public Car getObject() throws Exception {return new Car();
    }

    // 返回的额对应的是 class 文件
    @Override
    public Class<?> getObjectType() {return Car.class;}

    // 配置是不是单例
    @Override
    public boolean isSingleton() {return true;}

}

1.1.2.4 获取上文，获取 bean

package com.zt.spring;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class App {public static void main(String[] args) {
        // 获取上下文
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(MyBeanConfig.class);
        // 通过 FactoryBean 创立的 bean
        System.out.println(context.getBean(Car.class));
        // 通过 name 获取 car 的实体
        System.out.println(context.getBean("createRunnableFactoryBean"));
        context.close();}
}

1.1.3 通过另外一种工工厂模式实现 bena 的拆卸

1.1.3.1 创立一个 bean

package com.zt.spring;

public class Jeep {}

1.1.3.2 配置 Config 配置 bean

package com.zt.spring;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MyBeanConfig {

    @Bean
    public JeepFactory createJeepFactory() {return new JeepFactory();
    }

    @Bean
    public Jeep createJeep(JeepFactory factory) {return factory.creat();
    }
}

1.1.3.3 创立 Factory 实现构建办法 

package com.zt.spring;

public class JeepFactory {public Jeep creat() {return new Jeep();
    }
}

1.1.3.4 获取上文，获取 bean

package com.zt.spring;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class App {public static void main(String[] args) {
        // 获取上下文
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(MyBeanConfig.class);
        System.out.println(context.getBean("createJeep"));
        System.out.println(context.getBean(Jeep.class));
        context.close();}
}

1.2 spring 中 bean 的销毁办法

1.2.1 调用 spring 本人的初始化和销毁的办法

1.2.1.1 创立一个 bean

 并且继承 InitializingBean, DisposableBean , 实现 afterPropertiesSet，destroy 办法 
package com.zt.spring;

import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.InitializingBean;

public class User implements InitializingBean, DisposableBean {

    @Override
    public void afterPropertiesSet() throws Exception {System.out.println("=======afterPropertiesSet========");
    }

    @Override
    public void destroy() throws Exception {System.out.println("=======destroy========");
    }
}

1.2.1.2 在 conffig 文件中拆卸这个 bean

package com.zt.spring;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MyBeanConfig {

    @Bean
    public User createUser() {return new User();
    }
}

1.2.1.3 获取上下文 

package com.zt.spring;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class App {public static void main(String[] args) {
        // 获取上下文
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(MyBeanConfig.class);
        System.out.println(context.getBean(User.class));
        context.close();}
}

1.2.2 调用自定义初始化和销毁的办法

1.2.2.1 创立一个 bean

 自定义 init，destroy 办法 
package com.zt.spring;

public class Dog {
    //  初始化办法
    public void init() throws Exception {System.out.println("=======init========");
    }

    // 销毁的办法
    public void destroy() throws Exception {System.out.println("=======destroy========");
    }
}

1.2.2.2 在 conffig 文件中拆卸这个 bean

package com.zt.spring;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MyBeanConfig {@Bean(initMethod = "init",destroyMethod = "destroy")
    public Dog createDog() {return new Dog();
    }
}

1.2.2.3 获取上下文 

package com.zt.spring;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class App {public static void main(String[] args) {
        // 获取上下文
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(MyBeanConfig.class);
        System.out.println(context.getBean(Dog.class));
        context.close();}
}

1.2.3 调用自定义并且注解初始化和销毁的办法

1.2.3.1 创立一个 bean

 自定义 init，destroy 办法  在加上注解放 @PostConstruct，@PreDestroy 的形式实现 
package com.zt.spring;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;

public class UserInfo {

    @PostConstruct
    public void afterPropertiesSet() throws Exception {System.out.println("=======afterPropertiesSet========");
    }

    @PreDestroy
    public void destroy() throws Exception {System.out.println("=======destroy========");
    }
}

1.2.3.2 在 conffig 文件中拆卸这个 bean

package com.zt.spring;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MyBeanConfig {
    @Bean
    public UserInfo createUserInfo() {return new UserInfo();
    }
}

1.2.2.3 获取上下文 

package com.zt.spring;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class App {public static void main(String[] args) {
        // 获取上下文
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(MyBeanConfig.class);
        System.out.println(context.getBean(UserInfo.class));
        context.close();}
}

1.4 pom. 文件 

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com..zt</groupId>
    <artifactId>spring</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <project.build.sourceEncodding>UTF-8</project.build.sourceEncodding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.3.20.RELEASE</version>
        </dependency>
    </dependencies>


</project>

最初

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