How to Define Bean Name in java

/*
Pro Spring
By Rob Harrop
Jan Machacek
ISBN: 1-59059-461-4
Publisher: Apress
*/

///////////////////////////////////////////////////////////////////////////////
File: beans.xml











///////////////////////////////////////////////////////////////////////////////
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.xml.XmlBeanFactory;
import org.springframework.core.io.FileSystemResource;

public class BeanNaming {

public static void main(String[] args) {
BeanFactory factory = new XmlBeanFactory(new FileSystemResource(
"build/beans.xml"));

String s1 = (String)factory.getBean("string1");
String s2 = (String)factory.getBean("string2");
String s3 = (String)factory.getBean("java.lang.String");
}
}