Spring笔记2

1.　　三种实例化bean方法：

　　　　1）使用类构造器实例化

<bean id="personService" class="cn.itcast.service.imp.PersonServiceBean"></bean>

package cn.itcast.service.imp;

import cn.itcast.service.PersonService;

public class PersonServiceBean implements PersonService {
    public void save(){
        System.out.println("我是save方法");
    }
}

　　　　2）使用静态工厂方法实例化，factory-method="createOrder"：代表静态方法的方法名

<bean id="personService2" class="cn.itcast.service.imp.PersonServiceBeanFactory" factory-method="createOrder"></bean>

package cn.itcast.service.imp;

public class PersonServiceBeanFactory {
    public static PersonServiceBean createOrder(){
        return new PersonServiceBean();
    }
}

　　　　3）使用实例工厂方法实例化，先配一个bean的工厂类，然后再配bean，应用上一步配置的工厂类

<bean id="personServiceFactory" class="cn.itcast.service.imp.PersonServiceBeanFactory"></bean>
<bean id="personService3" factory-bean="personServiceFactory" factory-method="createOrder2"></bean>

package cn.itcast.service.imp;

public class PersonServiceBeanFactory {
    public static PersonServiceBean createOrder(){
        return new PersonServiceBean();
    }
    public PersonServiceBean createOrder2(){
        return new PersonServiceBean();
    }
}

2.　　　　bean的作用域：

　　　　1）scope="singleton"（默认）每个Spring Ioc容器中一个bean定义只有一个实例对象，默认情况下会在容器启动时初始化bean，但是我们可以指定bean节点的lazy-init="true"来延迟初始化bean，只有第一次获取bean对象才初始化bean。如：

<bean id='personService' class='cn.itcast.service.imp.PersonServiceBean' lazy-init="true"></bean>

如果想对所有bean都应用延迟初始化，可以在根节点beans设置default-lazy-init="true"。

　　　　2）scope="prototype"每次从容器获取bean都是一个新的对象

3.　　　　bean的初始化方法和销毁方法：（先实例化再执行初始化方法，即先执行构造方法，再执行init方法)

<bean id='personService' class='cn.itcast.service.imp.PersonServiceBean'  init-method="init" destroy-method="destory" ></bean>

　　　　调用destory方法用下面的对象：

AbstractApplicationContext ctr = new ClassPathXmlApplicationContext(new String[]{"beans.xml"});
ctr.close();

4.　　　　通过属性set方法注入（在运行期，由外部容器动态的将依赖对象注入到组件中）

　　　　1）对象的注入

package cn.itcast.service.imp;

import cn.itcast.dao.PersonDao;
import cn.itcast.service.PersonService;

public class PersonServiceBean implements PersonService {
    PersonDao personDao;
    
    public PersonDao getPersonDao() {
        return personDao;
    }

    public void setPersonDao(PersonDao personDao) {
        this.personDao = personDao;
    }
    
    public void save(){
        personDao.save();
    }
    
}

<bean id="personDao" class="cn.itcast.dao.imp.PersonDaoImp"></bean>
<bean id="personService" class="cn.itcast.service.imp.PersonServiceBean">
     <property name="personDao" ref="personDao"></property>
</bean>

 或者

<bean id="personService" class="cn.itcast.service.imp.PersonServiceBean">
        <property name="personDao">
            <bean class="cn.itcast.dao.imp.PersonDaoImp"></bean>
        </property>
</bean>

　　　　2）基本数据类型的注入，<property name="name" value="itcast"></property>

　　　　3）集合类型的注入：

<?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-2.5.xsd">
    <bean id="personDao" class="cn.itcast.dao.imp.PersonDaoImp"></bean>
    <bean id="personService" class="cn.itcast.service.imp.PersonServiceBean">
         <property name="personDao" ref="personDao"></property>
        <property name="sets">
            <set>
                <value>set1</value>
                <value>set2</value>
                <value>set3</value>
            </set>
        </property>
        <property name="lists">
            <list>
                <value>list1</value>
                <value>list2</value>
                <value>list3</value>
            </list>
        </property>
        <property name="properties">
            <props>
                <prop key="pro1">prov1</prop>
                <prop key="pro2">prov2</prop>
                <prop key="pro3">prov3</prop>
            </props>
        </property>
        <property name="maps">
            <map>
                <entry key="map1" value="mapv1"></entry>    
                <entry key="map2" value="mapv2"></entry>    
                <entry key="map3" value="mapv3"></entry>    
            </map>
        </property>
    </bean>
</beans>

package cn.itcast.service.imp;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;

import cn.itcast.dao.PersonDao;
import cn.itcast.service.PersonService;

public class PersonServiceBean implements PersonService {
    PersonDao personDao;
    
    String name;
    
    Set<String> sets = new HashSet<String>();
    
    List<String> lists = new ArrayList<String>();
    
    Properties properties = new Properties();
    
    Map<String,String> maps = new HashMap<String,String>();
    
    public Set<String> getSets() {
        return sets;
    }

    public void setSets(Set<String> sets) {
        this.sets = sets;
    }

    public List<String> getLists() {
        return lists;
    }

    public void setLists(List<String> lists) {
        this.lists = lists;
    }

    public Properties getProperties() {
        return properties;
    }

    public void setProperties(Properties properties) {
        this.properties = properties;
    }

    public Map<String, String> getMaps() {
        return maps;
    }

    public void setMaps(Map<String, String> maps) {
        this.maps = maps;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public PersonDao getPersonDao() {
        return personDao;
    }

    public void setPersonDao(PersonDao personDao) {
        this.personDao = personDao;
    }
    
    public void save(){
        System.out.println(name);
        personDao.save();
    }
    
}

package junit.test;

import java.util.Set;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.context.support.FileSystemXmlApplicationContext;

import cn.itcast.service.PersonService;

import junit.framework.TestCase;

public class SpringTest extends TestCase {

    @Test
    public void test1(){
        AbstractApplicationContext ctr = new ClassPathXmlApplicationContext(new String[]{"beans.xml"});
        PersonService personService = (PersonService) ctr.getBean("personService");
        for(String value:personService.getSets()){
            System.out.println(value);
        }
        for(String value:personService.getLists()){
            System.out.println(value);
        }
        for(Object key :personService.getProperties().keySet()){
            System.out.println(key+"_"+personService.getProperties().getProperty((String) key));
        }
        for(Object key :personService.getMaps().keySet()){
            System.out.println(key+"_"+personService.getMaps().get(key));
        }
    }
}

 5.　　　　通过构造器的方法注入

<?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-2.5.xsd">
    <bean id="personDao" class="cn.itcast.dao.imp.PersonDaoImp"></bean>
    <bean id="personService" class="cn.itcast.service.imp.PersonServiceBean">
         <constructor-arg index="0" type="cn.itcast.dao.PersonDao" ref="personDao"></constructor-arg>
         <constructor-arg index="1" value="传智博客"></constructor-arg>
                 </bean>
</beans>

package cn.itcast.service.imp;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;

import cn.itcast.dao.PersonDao;
import cn.itcast.service.PersonService;

public class PersonServiceBean implements PersonService {
    PersonDao personDao;
    
    String name;
    
    public PersonServiceBean(PersonDao personDao, String name) {
        this.personDao = personDao;
        this.name = name;
    }

    public void save(){
        System.out.println(name);
        personDao.save();
    }
    
}