In this post, we will see about Spring init-method and destroy-method.
When bean is instantiated or destroyed , there are some operations you may need to perform, so you can use init-method and destroy-method to call this methods while bean is being created or destroyed.
Lets understand it with the help of simple example:
For configuring spring in your eclipse ide please refer hello world example
When bean is instantiated or destroyed , there are some operations you may need to perform, so you can use init-method and destroy-method to call this methods while bean is being created or destroyed.
Lets understand it with the help of simple example:
For configuring spring in your eclipse ide please refer hello world example
1.Country.java:
This is simple pojo class which have only one attribute as countryName.
Create Country.java under package org.arpit.java2blog.Copy following content into Country.java.
package org.arpit.java2blog;
public class Country {
String countryName ;
public String getCountryName() {
return countryName;
}
public void setCountryName(String countryName) {
this.countryName = countryName;
}
public void init()
{
System.out.println("In init block of country");
}
public void destroy()
{
System.out.println("In destroy block of country");
}
}
2.SpringInitDestroyMain.java
This class contains main function.Create SpringInitDestroyMain.java under package org.arpit.java2blog.Copy following content into SpringInitDestroyMain.java
package org.arpit.java2blog;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class SpringInitDestroyMain{
public static void main(String[] args) {
AbstractApplicationContext appContext = new ClassPathXmlApplicationContext("ApplicationContext.xml");
Country countryObj = (Country) appContext.getBean("country");
System.out.println("Country Name: "+countryObj.getCountryName());
appContext.registerShutdownHook();
}
}
Here you need to register a shutdown hook registerShutdownHook() method that is declared on the AbstractApplicationContext class. This will ensures a graceful shutdown and calls the relevant destroy methods.
3.ApplicationContext.xml
4.Run it
When you will run above application,you will get following as output.
In init block of country Country Name: India In destroy block of country
Default Initialization and destroy method:
If you want to put default methods for all beans and do not want to configure of individual beans, you can use default-init-method and default-destroy-method with tag, so it will call init and destroy methods for all beans configured in ApplicationContext.xml.
