Bean Method invocation using spEL

Step 1 : Create the POJO

File : Customer.java

package com.simpleCodeStuffs.spEL;
public class Customer {

        private String name;
        private double bill;

        public String getName() {
                return name;
        }

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

        public double getBill() {
                return bill;
        }

        public void setBill(double bill) {
                this.bill = bill;
        }
}

File : Amount.java

package com.simpleCodeStuffs.spEL;
public class Amount {

        public double billAmount() {
                return 100.9;
        }
}

The scenario is such that the value of bill€™ attribute of ‘Customer’€™ depends on the value returned from ‘billAmount()’ method of ‘Amount’

Step 2 : Create the xml file

File : elBeans.xml

<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="cust" class="com.simpleCodeStuffs.spEL.Customer">
              <property name="name" value="#{'SANDY'.toLowerCase()}" />
               <property name="bill" value="#{amount.billAmount()}" />
        </bean>
        <bean id="amount" class="com.simpleCodeStuffs.spEL.Amount">
        </bean>
</beans>

Note here, method invocation is done on Amount class through the bean as
spEL #{amount.billAmount()} and the returned value is set to bill using injection.

Step 3 : Create the main class

File : MainClass.java

package com.simpleCodeStuffs.spEL;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class MainClass {

        public static void main(String[] args) {

             ApplicationContext context =
                new ClassPathXmlApplicationContext("elBeans.xml");
                Amount bill = (Amount) context.getBean("amount");
                Customer customer = (Customer) context.getBean("cust");

                System.out.println("Customer name: " + customer.getName());
                System.out.println("Bill amount: " + customer.getBill());
        }
}