File: context.properties
oracle.(class)=BookwormOracle
encyclopedia.(class)=HardcodedEncyclopedia
oracle.encyclopedia(ref)=encyclopedia
File: Main.java
import java.util.HashMap;
import java.util.Map;
import org.springframework.beans.factory.support.BeanDefinitionReader;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.beans.factory.support.PropertiesBeanDefinitionReader;
import org.springframework.core.io.ClassPathResource;
public class Main {
public static void main(String[] a) {
DefaultListableBeanFactory bf = new DefaultListableBeanFactory();
BeanDefinitionReader reader = new PropertiesBeanDefinitionReader(bf);
reader.loadBeanDefinitions(new ClassPathResource("context.properties"));
Oracle oracle = (Oracle) bf.getBean("oracle");
System.out.println("Meaning of life is " + oracle.defineMeaningOfLife());
}
}
interface Oracle {
String defineMeaningOfLife();
}
interface Encyclopedia {
Long findLong(String entry);
}
class BookwormOracle implements Oracle {
private Encyclopedia encyclopedia;
public String defineMeaningOfLife() {
Long ageOfUniverse = this.encyclopedia.findLong("AgeOfUniverse");
Long constantOfLife = this.encyclopedia.findLong("ConstantOfLife");
return String.valueOf(ageOfUniverse / constantOfLife);
}
public void setEncyclopedia(Encyclopedia encyclopedia) {
this.encyclopedia = encyclopedia;
}
}
class HardcodedEncyclopedia implements Encyclopedia {
private Map entryValues = new HashMap();
public HardcodedEncyclopedia() {
this.entryValues.put("AgeOfUniverse", 13700000000L);
this.entryValues.put("ConstantOfLife", 326190476L);
}
public Long findLong(String entry) {
return this.entryValues.get(entry);
}
}