2.SpringEL bean引用实例

SpringEL bean引用实例

介绍

在Spring EL，可以使用点(.)符号嵌套属性参考一个bean。例如，“bean.property_name”

public class Customer {@Value("#{addressBean.country}")private String country;
}

在上面的代码片段，它从"addressBean""bean注入了"country"属性到现在的"customer"类的"country"属性的值

Spring EL以注解的形式

使用 SpEL 引用一个bean，bean属性也它的方法

package com.yiibai.core;import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;@Component("customerBean")
public class Customer {@Value("#{addressBean}")private Address address;@Value("#{addressBean.country}")private String country;@Value("#{addressBean.getFullAddress('yiibai')}")private String fullAddress;//getter and setter methods@Overridepublic String toString() {return "Customer [address=" + address + "\n, country=" + country+ "\n, fullAddress=" + fullAddress + "]";}}

package com.yiibai.core;import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;@Component("addressBean")
public class Address {@Value("GaoDeng, QiongShang")private String street;@Value("571100")private int postcode;@Value("CN")private String country;public String getFullAddress(String prefix) {return prefix + " : " + street + " " + postcode + " " + country;}//getter and setter methodspublic void setCountry(String country) {this.country = country;}@Overridepublic String toString() {return "Address [street=" + street + ", postcode=" + postcode+ ", country=" + country + "]";}}

执行结果

Customer obj = (Customer) context.getBean("customerBean");
System.out.println(obj);

输出结果

Customer [address=Address [street=GaoDeng, QiongShang, postcode=571100, country=CN]
, country=CN
, fullAddress=yiibai : GaoDeng, QiongShang 571100 CN]

Spring EL以XML的形式

<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-3.0.xsd"><bean id="customerBean" class="com.yiibai.core.Customer"><property name="address" value="#{addressBean}" /><property name="country" value="#{addressBean.country}" /><property name="fullAddress" value="#{addressBean.getFullAddress('yiibai')}" /></bean><bean id="addressBean" class="com.yiibai.core.Address"><property name="street" value="GaoDeng, QiongShang" /><property name="postcode" value="571100" /><property name="country" value="CN" /></bean></beans>