Spring EL bean引用實例

在Spring EL，可以使用點(.)符號嵌套屬性參考一個bean。例如，「bean.property_name」。

public class Customer {

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

在上面的代碼片段，它從「addressBean」 bean注入了「country」屬性到現在的「customer」類的「country」屬性的值。

Spring EL以註解的形式

請參閱下面的例子，演示如何使用使用 SpEL 引用一個bean，bean屬性也它的方法。

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

@Override
public 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 methods

public void setCountry(String country) {
    this.country = country;
}

@Override
public String toString() {
    return "Address \[street=" + street + ", postcode=" + postcode
            + ", country=" + country + "\]";
}

}

執行結果

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

輸出結果

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

請參閱在XML文件定義bean的等效版本。

<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>

下載代碼 –  http://pan.baidu.com/s/1pJTgLUN