结合反射与XML实现Java编程的动态性

public class Basket {private Food food&＃61;null;public void put(Food food){this.food&＃61;food;}public Food get(){return this.food;}
}

public class Tomato implements Vegetable{private String color &＃61; null;public void display(){System.out.print("Hi,I am Tomato!");System.out.print("My color is "&＃43;color&＃43;".");}public String getColor() {return color;}public void setColor(String color) {this.color &＃61; color;}
}

public class Factory {private String file&＃61;null;public Factory(){}public Factory(String file){this.file&＃61;file;}public T getBean(){T ret&＃61;null;//read informations from foods.xml by dom4jSAXReader saxReader&＃61;new SAXReader();Document doc&＃61;null;try {doc&＃61;saxReader.read(new File(file));} catch (DocumentException e) {e.printStackTrace();}//kind is the value of the "choice" element in foods.xml String kind&＃61;doc.selectSingleNode("foods/choice").getText();Element element&＃61;(Element)doc.selectSingleNode("foods/"&＃43;kind&＃43;"/"&＃43;kind.substring(0, kind.length()-1));//use hashtable to save all properties of a classHashtable hashtbl&＃61;new Hashtable();//read the food name and its corresponding class String name&＃61;element.attribute("name").getValue();String className&＃61;element.attribute("class").getValue();//read all properperties informations,that is name,type and valueList list1&＃61;element.selectNodes("property");Iterator iterator1&＃61;list1.iterator();while(iterator1.hasNext()){Element element1&＃61;iterator1.next();String propertyName&＃61;element1.attribute("name").getValue();String propertyType&＃61;element1.attribute("type").getValue();String propertyValue&＃61;element1.element("value").getText();//record all the properties and values in a hashtablehashtbl.put(propertyName, propertyType&＃43;";"&＃43;propertyValue);}//call the method to create a object ret&＃61;newInstance(name,className,hashtbl);return ret;}private T newInstance(String name,String className,Hashtable hashtbl){T ret&＃61;null;try {//create object by reflectionret&＃61;(T)Class.forName(className).newInstance();} catch (Exception e) {e.printStackTrace();}for(String key:hashtbl.keySet()){char [] temp&＃61;key.toCharArray();temp[0]&＃61;(char)(temp[0]-32);String methodName&＃61;"set"&＃43;new String(temp);String value&＃61;hashtbl.get(key).split(";")[1];Class type&＃61;null;try {//read property type by reflectiontype&＃61;Class.forName(hashtbl.get(key).split(";")[0]);} catch (ClassNotFoundException e) {e.printStackTrace();}try {//get method object by reflectionMethod m&＃61;ret.getClass().getMethod(methodName, type);//call method by reflectionm.invoke(ret, value);} catch (Exception e) {e.printStackTrace();}}return ret;}
}

public class Person { public void choose(Basket basket){ Factory factory&＃61;new Factory("foods.xml"); Food food&＃61;factory.getBean(); basket.put(food); } public Food pay(Basket basket){ return basket.get(); }
}

vegetables red nice >

public class Test {public static void main(String[] args) {Person peoson&＃61;new Person();Basket basket&＃61;new Basket();peoson.choose(basket);Food food&＃61;peoson.pay(basket);food.display();}
}

Hi,I am Tomato!My color is red.

Hi,I am Pear!My shape is nice.