package org.mule.util.queue;

import java.util.HashMap;
import java.io.File;

public class FilePersistenceQueueIDGenerator {

    long persistenceID=1000;
    
    HashMap <String,HashMap<String,File>> fileMap=new HashMap<String,HashMap<String,File>>();
    
    protected FilePersistenceQueueIDGenerator() {
         // ...
    }       
    static private FilePersistenceQueueIDGenerator _instance = null;
   
    static public FilePersistenceQueueIDGenerator getInstance() {
        if(null == _instance) {
            _instance = new FilePersistenceQueueIDGenerator();
        }
        return _instance;
    }
   
    public synchronized void updateQueueID(long id){
        if (persistenceID<id) persistenceID=id;
    }
   
    public synchronized void updateQueueID(String id){
        try{
            long lid=Long.parseLong(id);
            updateQueueID(lid);
        }catch(Throwable t){}
    }
   
    public synchronized long generateID(){
        persistenceID++;
        return persistenceID;
    }
    
    public void clearFileMap(){
    	fileMap=new HashMap<String,HashMap<String,File>>();
    }
    
    public void clearFileQueuedMap(String queue){
    	if (fileMap.containsKey(queue)) fileMap.remove(queue);
    }
    
    public void putInFileMap(String queue,String id,File f){
    	if (!fileMap.containsKey(queue)) fileMap.put(queue,new HashMap<String,File>());
    	fileMap.get(queue).put(id, f);
    }
    
    public File getFromFileMap(String queue,String id){
    	if (!fileMap.containsKey(queue)) return null;
    	return fileMap.get(queue).get(id);
    }

    public File peekFromFileMap(String queue,String id){
    	HashMap <String,File> shm=fileMap.get(queue);
    	if (shm==null) return null;
    	File f=shm.get(id);
    	if (f!=null) shm.remove(id);
    	return f;
    }
    
    public void removeInFileMap(String queue,String id){
    	if (!fileMap.containsKey(queue)) return;
    	fileMap.get(queue).remove(id);
    }
}