SSH框架构造之三---------------spring 注入

spring的三种注入方式：

接口注入（不推荐）
getter，setter方式注入（比较常用）也是上篇中使用的方式
构造器注入（死的应用）

关于getter和setter方式的注入：

autowire="defualt" //是上篇中使用的方式
autowire=“byName”
autowire="bytype"

例如：有如下两个类需要注入

1 package org.jia;

2

3 public class Order {

4 private String orderNum;

5 @SuppressWarnings("unused")

6 private OrderItem orderitem;

7

8 public OrderItem getOrderitem() {

9 return orderitem;

10 }

11

12 public void setOrderitem(OrderItem orderitem) {

13 this.orderitem = orderitem;

14 }

15

16 public String getOrderNum() {

17 return orderNum;

18 }

19

20 public void setOrderNum(String orderNum) {

21 this.orderNum = orderNum;

22 }

23

24 }

25 package org.jia;

26

27 public class OrderItem {

28 private String orderdec;

29

30 public String getOrderdec() {

31 return orderdec;

32 }

33

34 public void setOrderdec(String orderdec) {

35 this.orderdec = orderdec;

36 }

37 }

38
getter&&setter方式第一种注入：

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">

<beans>

<bean id="orderItem" class="org.jia.OrderItem">

<property name="orderdec" value="item00001"></property>

</bean>

<bean id="order" class="org.jia.Order" >

<!-----注入变量 名字必须与类中的名字一样------->

<property name="orderNum" value="order000007"></property>

<！--注入对象 名字为orderitem，所属的类的应用id为orderItem-->

<property name="orderitem" ref="orderItem"></property>

--></bean>

</beans>
getter&&setter方式第二种注入： byName

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">

<beans>

<!--此时的id就必须与Order.java中所定义的OrderItem的对象名称一样了，不然就会找不到-->

<bean id="orderitem" class="org.jia.OrderItem">

<property name="orderdec" value="item00001"></property>

</bean>

<bean id="order" class="org.jia.Order" autowire="byName">

<property name="orderNum" value="order000007"></property>

</bean>

</beans>
getter&&setter方式第三种注入：byType

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">

<beans>

<!--按照byType注入则就与id没有关系，可以随便定义id ！！！但是不能出现多个此类的id-->

<bean id="orderitdfadafaem" class="org.jia.OrderItem">

<property name="orderdec" value="item00001"></property>

</bean>

<bean id="order" class="org.jia.Order" autowire="byType">

<property name="orderNum" value="order000007"></property>

</bean>

</beans>

关于构造器的注入：

autowire="constructor"

需要在Order.java中加入一个构造器

public Order(OrderItem item ){ orderitem = item; }

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">

<beans>

<bean id="orderItem" class="org.jia.OrderItem">

<property name="orderdec" value="item00001"></property>

</bean>

<bean id="order" class="org.jia.Order" autowire="constructor">

<property name="orderNum" value="order000007"></property>

</bean>

</beans>


关于无法使用scope 为session等的解決方法:

1. 在web.xml文件中添加listener


<listener>

<listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>

</listener>

2. 相應的spring bean配置中應加入<aop:scoped-proxy/>此行代碼

xmlns="http://www.springframework.org/schema/beans"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xmlns:p="http://www.springframework.org/schema/p"

xmlns:aop="http://www.springframework.org/schema/aop"

xsi:schemaLocation="http://www.springframework.org/schema/beans

http://www.springframework.org/schema/beans/spring-beans-2.5.xsd

http://www.springframework.org/schema/aop

http://www.springframework.org/schema/aop/spring-aop-2.5.xsd"

<bean id="userAction" class="org.gecs.mes.common.action.UserAction" autowire="byName" scope="session">

<aop:scoped-proxy/>

</bean>