UserCache.java

package com.delect.motiver.server.cache;

import java.util.HashMap;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;

import net.sf.jsr107cache.Cache;
import net.sf.jsr107cache.CacheException;
import net.sf.jsr107cache.CacheFactory;
import net.sf.jsr107cache.CacheManager;

import com.delect.motiver.server.jdo.Circle;
import com.delect.motiver.server.jdo.UserOpenid;
import com.delect.motiver.server.service.MyServiceImpl;
import com.google.appengine.api.memcache.jsr107cache.GCacheFactory;
import com.prodeagle.java.counters.Counter;

public class UserCache {

  private final static boolean CACHE_ON = true;
  
  private final static int CACHE_EXPIRE_SECONDS = 604800;
  
  /**
   * Logger for this class
   */
  private static final Logger logger = Logger.getLogger(UserCache.class.getName());

  private static final String PREFIX_CIRCLE = "uc_ci";
  private static final String PREFIX_USER = "uc_us";
  
  private static Cache cache; 
  private static UserCache userCache; 

  public static UserCache getInstance() {
    if(cache == null) {
      try {
        Map props = new HashMap();
        props.put(GCacheFactory.EXPIRATION_DELTA, CACHE_EXPIRE_SECONDS);
        CacheFactory cacheFactory = CacheManager.getInstance().getCacheFactory();
        cache = cacheFactory.createCache(props);
      } catch (CacheException e) {
        logger.log(Level.SEVERE, "Error loading cache", e);
      }
    }
    
    if(userCache == null) {
      userCache = new UserCache();
    }
    return userCache;
  }

  public void addCircle(Circle circle) {
    
    if(cache == null || !CACHE_ON) {
      return;
    }
    
    if(logger.isLoggable(Level.FINE)) {
      logger.log(Level.FINE, "Saving permission circle: "+circle);
    }
    
    StringBuilder builder = MyServiceImpl.getStringBuilder();
    builder.append(PREFIX_CIRCLE);
    builder.append("_");
    builder.append(circle.getTarget());
    builder.append("_");
    builder.append(circle.getUid());
    builder.append("_");
    builder.append(circle.getFriendId());
    
    cache.put(builder.toString(), circle);
      
  }

  public void removeCircle(Circle circle) {
    
    if(cache == null || !CACHE_ON) {
      return;
    }
    
    if(logger.isLoggable(Level.FINE)) {
      logger.log(Level.FINE, "Removing permission circle: "+circle);
    }
    
    StringBuilder builder = MyServiceImpl.getStringBuilder();
    builder.append(PREFIX_CIRCLE);
    builder.append("_");
    builder.append(circle.getTarget());
    builder.append("_");
    builder.append(circle.getUid());
    builder.append("_");
    builder.append(circle.getFriendId());
    
    cache.remove(builder.toString());
      
  }

  public Circle getCircle(int target, String uid, String friendUid) {
    
    if(cache == null || !CACHE_ON) {
      return null;
    }

    StringBuilder builder = MyServiceImpl.getStringBuilder();
    builder.append(PREFIX_CIRCLE);
    builder.append("_");
    builder.append(target);
    builder.append("_");
    builder.append(uid);
    builder.append("_");
    builder.append(friendUid);
    Object obj = cache.get(builder.toString());
    
    Circle c = null;
    if(obj != null && obj instanceof Circle) {
      c = (Circle)obj;
    }
    
    if(logger.isLoggable(Level.FINE)) {
      logger.log(Level.FINE, "Loaded permission circle ("+target+", "+uid+", "+friendUid+"): "+c);
    }
    
    return c;
  }

  public UserOpenid getUser(String uid) {
    
    if(cache == null || !CACHE_ON) {
      return null;
    }
    
    if(logger.isLoggable(Level.FINE)) {
      logger.log(Level.FINE, "Loading user ("+uid+")");
    }
    
    StringBuilder builder = MyServiceImpl.getStringBuilder();
    builder.append(PREFIX_USER);
    builder.append(uid);
    Object obj = cache.get(builder.toString());
    
    UserOpenid t = null;
    if(obj != null && obj instanceof UserOpenid) {

      //prodeagle counter
      Counter.increment("Cache.User");
      
      t = (UserOpenid)obj;
    }
    
    if(logger.isLoggable(Level.FINE)) {
      logger.log(Level.FINE, "Loaded user: "+t);
    }
    
    return t;
  }

  public void setUser(UserOpenid user) {
    
    if(cache == null || !CACHE_ON) {
      return;
    }
    
    if(logger.isLoggable(Level.FINE)) {
      logger.log(Level.FINE, "Saving user: "+user);
    }
    
    StringBuilder builder = MyServiceImpl.getStringBuilder();
    builder.append(PREFIX_USER);
    builder.append(user.getUid());
    cache.put(builder.toString(), user);
    
  }

  public void removeUser(String userId) {
    
    if(cache == null || !CACHE_ON) {
      return;
    }
    
    if(logger.isLoggable(Level.FINE)) {
      logger.log(Level.FINE, "Removing user, ID: "+userId);
    }
    
    StringBuilder builder = MyServiceImpl.getStringBuilder();
    builder.append(PREFIX_USER);
    builder.append(userId);
    cache.remove(builder.toString());
  }
}