Spring – Static variable Dependency Injection | Code Factory

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• To inject static variable normal way of declaring <bean> is not useful.
• By using MethodInvokingFactoryBean class we pass static variable vallues.

<bean class="org.springframework.beans.factory.config.MethodInvokingFactoryBean" />

• MethodInvokingFactoryBean have 2 methods
  • setArguments(Object[] arguments)
  • setStaticMethod(String staticMethod)

Create Java Project

• Open Eclipse
• Go to File -> New -> Others… -> Java Project
• Create DI-StaticVariable project
• Right click on project -> Build Path -> Configure Build Path -> Libraries tab -> Add External JARs
  • commons-logging-X.X.jar
  • spring-beans-X.X.X.jar
  • spring-context-X.X.X.jar
  • spring-core-X.X.X.jar
• * You can find dtd information from spring-beans-X.X.X.jar -> org -> springframework -> beans -> factory -> xml -> spring-beans.dtd (line no 36 & 37)

spring.xml

<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN 2.0//EN"
	"http://www.springframework.org/dtd/spring-beans-2.0.dtd">

<beans>
	<bean id="c" class="com.codeFactory.beans.Car" />
	
	<!-- static variable DI -->
	<bean class="org.springframework.beans.factory.config.MethodInvokingFactoryBean" >
		<property name="staticMethod" value="com.codeFactory.beans.Car.setCompanyName" />
		<property name="arguments">
			<list>
				<value>JLR</value>
			</list>
		</property>
	</bean>
</beans>

Car.java

package com.codeFactory.beans;

/**
 * @author code.factory
 *
 */
public class Car {
	private static String companyName;

	public static void setCompanyName(String companyName) {
		Car.companyName = companyName;
	}

	public static void print() {
		System.out.println("Company Name " + companyName);
	}
}

Client.java

package com.codeFactory.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.codeFactory.beans.Car;

/**
 * @author code.factory
 *
 */
public class Client {
	public static void main(String... args) {	
		ApplicationContext context = new ClassPathXmlApplicationContext("com/codeFactory/resources/spring.xml");

		Car t = (Car) context.getBean("c");
		t.print();
	}
}

Output:

Company Name JLR