In Spring EL, you can reference a bean, and nested properties using a ‘dot (.
)‘ symbol. For example, “bean.property_name
“.
public class Customer {
@Value("#{addressBean.country}")
private String country;
In above code snippet, it inject the value of “country
” property from “addressBean
” bean into current “customer
” class, “country
” property.
Spring EL in Annotation
See following example, show you how to use SpEL to reference a bean, bean property and also it’s method.
package com.mkyong.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('mkyong')}")
private String fullAddress;
//getter and setter methods
@Override
public String toString() {
return "Customer [address=" + address + "\n, country=" + country
+ "\n, fullAddress=" + fullAddress + "]";
}
}
package com.mkyong.core;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
@Component("addressBean")
public class Address {
@Value("Block ABC, LakeView")
private String street;
@Value("98700")
private int postcode;
@Value("US")
private String country;
public String getFullAddress(String prefix) {
return prefix + " : " + street + " " + postcode + " " + country;
}
//getter and setter methods
public void setCountry(String country) {
this.country = country;
}
@Override
public String toString() {
return "Address [street=" + street + ", postcode=" + postcode
+ ", country=" + country + "]";
}
}
连私有属性都可以直接访问
Run it
Customer obj = (Customer) context.getBean("customerBean");
System.out.println(obj);
Output
Customer [address=Address [street=Block ABC, LakeView, postcode=98700, country=US]
, country=US
, fullAddress=mkyong : Block ABC, LakeView 98700 US]
Spring EL in XML
See equivalent version in bean definition XML file.
<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-3.0.xsd">
<bean id="customerBean" class="com.mkyong.core.Customer">
<property name="address" value="#{addressBean}" />
<property name="country" value="#{addressBean.country}" />
<property name="fullAddress" value="#{addressBean.getFullAddress('mkyong')}" />
</bean>
<bean id="addressBean" class="com.mkyong.core.Address">
<property name="street" value="Block ABC, LakeView" />
<property name="postcode" value="98700" />
<property name="country" value="US" />
</bean>
</beans>