Spring学习（三）

发表于 2023-07-23 更新于 2023-08-16 分类于计算机学习，框架， Spring 阅读次数：

Bean作用域

package com.xiaoguan.bean;

public class SpringBean {
    public SpringBean() {
        System.out.println("spring的无参数构造方法执行了");
    }
}

<?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 class="org.springframework.beans.factory.config.CustomScopeConfigurer">
        <property name="scopes">
            <map>
                <entry key="myThread" >
                    <bean class="org.springframework.context.support.SimpleThreadScope"></bean>
                </entry>
            </map>
        </property>
    </bean>
    <bean id="sb" class="com.xiaoguan.bean.SpringBean" scope="myThread"></bean>
    <!--web项目中还有request和session请求域request一次请求中一个bean，session一次会话中一个bean-->
</beans>

package com.xiaoguan.test;

import com.xiaoguan.bean.SpringBean;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class ScopeTest {
    @Test
    public void testThreadScope(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring-scope.xml");
        SpringBean sb = applicationContext.getBean("sb", SpringBean.class);
        System.out.println(sb);
        new Thread(new Runnable() {
            @Override
            public void run() {
                SpringBean sb1 = applicationContext.getBean("sb", SpringBean.class);
                System.out.println(sb1);
            }
        }).start();
    }
    @Test
    public void testBeanScope(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring-scope.xml");
        SpringBean sb = applicationContext.getBean("sb", SpringBean.class);
        System.out.println(sb);
        SpringBean sb2 = applicationContext.getBean("sb", SpringBean.class);
        System.out.println(sb2);
        SpringBean sb3 = applicationContext.getBean("sb", SpringBean.class);
        System.out.println(sb3);
    }
}

工厂模式

package com.xiaoguan.factorymethod;

public class Dogger extends Weapon{
    @Override
    public void attack() {
        System.out.println("砍丫的");
    }
}

package com.xiaoguan.factorymethod;

public class DoggerFactory extends WeaponFactory{
    @Override
    public Weapon get() {
        return new Dogger();
    }
}

package com.xiaoguan.factorymethod;

public class Gun extends Weapon{
    @Override
    public void attack() {
        System.out.println("开火");
    }
}

package com.xiaoguan.factorymethod;

public class GunFactory extends WeaponFactory{
    @Override
    public Weapon get() {
        return new Gun();
    }
}

package com.xiaoguan.factorymethod;

public class Test {
    public static void main(String[] args) {
        WeaponFactory factory=new DoggerFactory();
        Weapon weapon = factory.get();
        weapon.attack();
    }
}

package com.xiaoguan.factorymethod;

abstract public class Weapon {
    public abstract void attack();
}

package com.xiaoguan.factorymethod;

abstract public class WeaponFactory {
    public abstract  Weapon get();
}

package com.xiaoguan.simpleFactory;

public class Dagger extends Weapon{
    @Override
    public void attack() {
        System.out.println("砍丫的");
    }
}

package com.xiaoguan.simpleFactory;

public class Fighter extends Weapon{
    @Override
    public void attack() {
        System.out.println("战斗机发射");
    }
}

package com.xiaoguan.simpleFactory;

public class Tank extends Weapon{
    @Override
    public void attack() {
        System.out.println("坦克开炮");
    }
}

package com.xiaoguan.simpleFactory;

public class Test {
    public static void main(String[] args) {
        Weapon tank = WeaponFactory.get("Tank");
        tank.attack();

    }
}

package com.xiaoguan.simpleFactory;

public abstract class Weapon {
    public abstract void attack();
}

package com.xiaoguan.simpleFactory;

public class WeaponFactory {
    public static Weapon get(String weanponType){
        if ("Tank".equals(weanponType)) {
            return new Tank();
        }else if ("Fighter".equals(weanponType)){
            return new Fighter();
        } else if ("Dagger".equals(weanponType)) {
            return new Dagger();
        }else {
            throw new RuntimeException("不支持该武器生产");
        }
    }
}

Bean实例化

package com.xiaoguan.bean;

import org.springframework.beans.factory.FactoryBean;

import java.text.SimpleDateFormat;
import java.util.Date;

public class DataFactoryBean implements FactoryBean<Date> {
    private String strDate;
    public DataFactoryBean(String strDate) {
        this.strDate = strDate;
    }

    @Override
    public Date getObject() throws Exception {
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss SS");
        Date parse = simpleDateFormat.parse(strDate);
        return parse;
    }

    @Override
    public Class<?> getObjectType() {
        return null;
    }
}

package com.xiaoguan.bean;

public class Gun {
    public Gun() {
        System.out.println("gun的无参数构造方法执行了");
    }
}

package com.xiaoguan.bean;

public class GunFactory {
    public Gun get(){
        return new Gun();
    }
}

package com.xiaoguan.bean;

public class Person {
    public Person() {
        System.out.println("Person的构造方法执行了");
    }
}

package com.xiaoguan.bean;

import org.springframework.beans.factory.FactoryBean;

public class PersonFactoryBean implements FactoryBean<Person> {
    @Override
    public Person getObject() throws Exception {
        return new Person();
    }

    @Override
    public Class<?> getObjectType() {
        return null;
    }
//默认已经实现，表示单例，如果不想单例可以改为return false
    @Override
    public boolean isSingleton() {
        return true;
    }
}

package com.xiaoguan.bean;

public class SpringBean {
    public SpringBean() {
        System.out.println("SpringBean的无参数构造方法执行了");
    }
}

package com.xiaoguan.bean;

public class Star {
    public Star() {
        System.out.println("start的无参数构造方法执行了");
    }
}

package com.xiaoguan.bean;

public class StarFactory {
    public static Star get(){
        return new Star();
    }
}

package com.xiaoguan.bean;

import java.util.Date;

public class Student {
    private Date birth;

    @Override
    public String toString() {
        return "Student{" +
                "birth=" + birth +
                '}';
    }

    public void setBirth(Date birth) {
        this.birth = birth;
    }
}

<?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">
<!--    Spring提供实例化方式的第一种,在spring配置文件中直接配置全路径，spring会自动调用该类的无参数构造方法来实例化bean
            1.通过构造方法来实例化
            2.通过简单工厂模式实例化
            3.通过factory-bean实例化
            4.通过FactoryBean接口实例化-->
    <bean id="sb" class="com.xiaoguan.bean.SpringBean"/>
<!--    通过简单工厂模式实例化-->
    <bean id="sf" class="com.xiaoguan.bean.StarFactory" factory-method="get"/>
<!--    通过factory-bean实例化-->
    <bean id="gunFactory" class="com.xiaoguan.bean.GunFactory"/>
    <bean id="gun" factory-bean="gunFactory" factory-method="get"/>
<!--    通过FactoryBean接口实例化-->
    <bean id="person" class="com.xiaoguan.bean.PersonFactoryBean"/>
    <!--练习-->
    <bean id="student" class="com.xiaoguan.bean.Student">
<!--        <property name="birth" value="Mon Oct 10 14:30:26 CST 2022"/>-->
        <property name="birth" ref="nowTime"/>
    </bean>
    <bean id="nowTime" class="java.util.Date"/>
    <bean id="strDate" class="com.xiaoguan.bean.DataFactoryBean">
        <constructor-arg index="0" value="1980-10-11 20:30:30 40"/>
    </bean>
    <bean id="students" class="com.xiaoguan.bean.Student" >
        <property name="birth" ref="strDate"/>
    </bean>
</beans>

package com.xiaoguan.test;

import com.xiaoguan.bean.*;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class BeanInstatiation {
    @Test
    public void testInstatiation5() {
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("spring.xml");
        Student students = applicationContext.getBean("students", Student.class);
        System.out.println(students);
    }
        @Test
    public void testInstatiation4(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        Person person = applicationContext.getBean("person", Person.class);
        System.out.println(person);
    }
    @Test
    public void testInstatiation3(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        Gun gun = applicationContext.getBean("gun", Gun.class);
        System.out.println(gun);
    }
    @Test
    public void testInstatiation2(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        Star st = applicationContext.getBean("sf", Star.class);
        System.out.println(st);
    }
    @Test
    public void testInstatiation1(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        SpringBean sb = applicationContext.getBean("sb", SpringBean.class);
        System.out.println(sb);
    }
}