使用反射生成并操作对象

a=java.util.Date
b=javax.swing.JFrame
b%title=Title

package demo;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

public class ObjectPoolFactory {
    //定义一个对象池
    private Map<String, Object> objectPool = new HashMap<String, Object>();
    private Properties props = new Properties();
    
    /**
     * 定义一个创建对象的方法
     * @param clazzName
     * @return
     * @throws ClassNotFoundException
     * @throws InstantiationException
     * @throws IllegalAccessException
     */
    private Object createObject(String clazzName) throws ClassNotFoundException, InstantiationException, IllegalAccessException{
        //根据字符串获取对应的class对象
        Class clazz = Class.forName(clazzName);
        //使用clazz对应类的默认构造器创建实例
        return clazz.newInstance();
    }
    
    /**
     * 初始化properties对象
     * @param fileName
     * @throws IOException
     */
    public void init(String fileName) throws IOException{
        FileInputStream fis = new FileInputStream(fileName);
        props.load(fis);
    }
    
    /**
     * 根据指定文件来初始化对象池
     * 它会根据配置文件来创建对象
     * @throws IOException 
     * @throws IllegalAccessException 
     * @throws InstantiationException 
     * @throws ClassNotFoundException 
     */
    public void initPool() throws IOException, ClassNotFoundException, InstantiationException, IllegalAccessException{
        
        for (String name : props.stringPropertyNames()) {
            //每取出一对key-value对，就根据value创建一个对象
            //调用createObject()创建对象，并将对象添加到对象池中
            System.out.println(name);
            if(!name.contains("%")){
                objectPool.put(name, createObject(props.getProperty(name)));
            }
        }
    }
    
    /**
     * 该方法根据属性文件来调用指定对象的setter方法
     * @throws SecurityException 
     * @throws NoSuchMethodException 
     * @throws InvocationTargetException 
     * @throws IllegalArgumentException 
     * @throws IllegalAccessException 
     */
    public void initProperty() throws NoSuchMethodException, SecurityException, IllegalAccessException, IllegalArgumentException, InvocationTargetException{
        for (String name : props.stringPropertyNames()) {
            //key用于控制对象的setter方法设置值
            //%前面是对象名字，后面是setter方法名
            if(name.contains("%")){
                String[] strs = name.split("%");
                Object target = getObject(strs[0]);
                String method = "set" + strs[1].substring(0, 1).toUpperCase() +
                        strs[1].substring(1);
                //获取对象实现类多对应的Class对象
                Class targetClass = target.getClass();
                //获取希望调用的setter方法
                Method mtd = targetClass.getMethod(method, String.class);
                //通过Method的invoke方法执行setter方法
                mtd.invoke(target, props.getProperty(name));
            }
        }
    }
    
    /**
     * 获取对象
     */
    public Object getObject(String name){
        //从objectPool中取出指定name对应的对象
        return objectPool.get(name);
    }
    
    public static void main(String[] args) throws ClassNotFoundException, InstantiationException, IllegalAccessException, IOException, NoSuchMethodException, SecurityException, IllegalArgumentException, InvocationTargetException {
        ObjectPoolFactory pf = new ObjectPoolFactory();
        pf.init("obj.txt");
        pf.initPool();
        pf.initProperty();
        System.out.println(pf.getObject("a"));
        System.out.println(pf.getObject("b"));
    }
    
    
}

b
a
b%title
Wed Apr 27 21:51:20 CST 2016
javax.swing.JFrame[frame0,0,0,0x0,invalid,hidden,layout=java.awt.BorderLayout,title=Title,resizable,normal,defaultCloseOperation=HIDE_ON_CLOSE,rootPane=javax.swing.JRootPane[,0,0,0x0,invalid,layout=javax.swing.JRootPane$RootLayout,alignmentX=0.0,alignmentY=0.0,border=,flags=16777673,maximumSize=,minimumSize=,preferredSize=],rootPaneCheckingEnabled=true]