package com.dy.common.mw.protocol;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

public class PrefixedDataAvailablePool {
	
	protected static HashMap<String, List<PrefixedDataAvailable>> pool = new HashMap<>() ;
	
	/**
	 * 生成对象
	 * 线程非安全的，所以用到synchronized
	 * @param clazz 预处理类
	 * @return 预处理类对象
	 */
	public static synchronized PrefixedDataAvailable getInstance(Class<?> clazz)throws Exception {
		if(pool == null){
			pool = new HashMap<>() ;
		}
		String className = clazz.getName() ;
		PrefixedDataAvailable obj = null ;
		
		List<PrefixedDataAvailable> list = pool.get(className) ;
		if(list == null){
			list = new ArrayList<>() ;
			pool.put(className, list) ;
		}else if(list.size() > 0){
			obj = list.get(0) ;
			list.remove(0) ;
		}
		
		if(obj == null){
			try {
				obj = (PrefixedDataAvailable)clazz.getDeclaredConstructor().newInstance() ;
				//obj = (PrefixedDataAvailable)clazz.newInstance();
			} catch (Exception e) {
				throw new Exception( "由" + className + "生成实例失败！");
			}
		}
		return obj ;
	}
	
	/**
	 * 把对象放回池中
	 * @param clazz 预处理类
	 * @param obj  预处理类对象
	 */
	public static void freeInstance(Class<?> clazz, PrefixedDataAvailable obj) {
		if(pool != null){
			String className = clazz.getName() ;
			List<PrefixedDataAvailable> list = pool.get(className) ;
			if(list != null){
				list.add(obj) ;
			}
		}
	}	
	
}