RHelper.java

package com.kull.android;

import java.lang.reflect.Field;
import java.lang.reflect.Type;
import java.util.HashMap;
import java.util.Map;

import android.content.Context;

import com.kull.ObjectHelper;

public class RHelper {

	
	public enum RType{
		id,attr,style,
		layout,menu,string,
		color,dimen,anim,
		drawable,styleable;
		
		
	}
	private static Map<String, Integer> CACHE_IDS=new HashMap<String, Integer>();
	private static Map<String, Integer[]> CACHE_IDARRAYS=new HashMap<String, Integer[]>();
	//private static Map<RType,Map<String, Integer>> IDS=new HashMap<RType,Map<String, Integer>>();
	private static boolean hasInited=false;
	
	public static void init(Class... clsRs) throws Exception{
		if(hasInited)return;
		for(Class clsR :clsRs){
			if(!"R".equals(clsR.getSimpleName())){
				throw new Exception("this class must be R");
			}
			
			Class[] clss=  clsR.getDeclaredClasses();
			for(RType rType :RType.values()){
				//IDS.put(rType, new HashMap<String, Integer>());
				
				for(Class cls :clss){
					String clsName=cls.getSimpleName();
					if(!clsName.equals(rType.name()))continue;
					Field[] fields=cls.getDeclaredFields();
					for(Field field :fields){
						    String fname=field.getName();
							String key=getKey(rType, fname);
							Type ft=field.getType();
					        if(Integer.class.equals(ft)){		
							  CACHE_IDS.put(key, field.getInt(cls));
					        }else if(Integer[].class.equals(ft)){
					        	CACHE_IDARRAYS.put(key, (Integer[])field.get(cls));
					        }
					        
					}
				}
				
			}
		}
	}
	
	private static String getKey(RType rtype,String name){
		return rtype.name()+":"+name;
	}
	
	public static int getResourceIdByName(RType rtype,String name) throws NullPointerException{
		String key=getKey(rtype, name);
		if(CACHE_IDS.containsKey(key)){
			return CACHE_IDS.get(key);
		}else throw new NullPointerException(rtype.name()+":"+name+" is not exist");
		
		
	}
	
	public static int getResourceIdByName(String name)throws NullPointerException{
		
		for(RType rtype :RType.values()){
			String key=getKey(rtype, name);
			if(CACHE_IDS.containsKey(key)){
				return CACHE_IDS.get(key);
			}
		}
		throw new NullPointerException(name+" is not exist");
		
	}
	
	
	public static int getResourceByKey(String key) throws NullPointerException{
		
		if(CACHE_IDS.containsKey(key)){
			return CACHE_IDS.get(key);
		}else throw new NullPointerException(key+" is not exist");
		
		
	}
	
	
	public static String getString(Context context, String name){
		String key=getKey(RType.string, name);
		if(CACHE_IDS.containsKey(key)){
			return context.getString(CACHE_IDS.get(key));
		}else throw new NullPointerException(name+" is not exist");
	}
	
	
	
	
}