package com.trendmicro.grid.acl.metadata;
   
   import com.trendmicro.grid.acl.commons.collections.StringCache;
   
   import java.util.concurrent.ConcurrentMap;
   
   /**
    * Implements a string cache that can be used to reduce the memory footprint of Metadata elements
    * by sharing instances of equal strings.
   *
   * @author juergen_kellerer, 2010-06-25
   * @version 1.0
   */
  public class MetadataStringCache extends StringCache {
  
  	private static final long serialVersionUID = -714419543858155943L;
  
  	boolean includeStringValues;
  
  	public MetadataStringCache() {
  	}
  
  	public MetadataStringCache(ConcurrentMap<String, String> cache, boolean includeStringValues) {
  		super(cache);
  		this.includeStringValues = includeStringValues;
  	}
  
  	/**
  	 * Shares the strings in the given metadata element.
  	 *
  	 * @param metadata the element to share the strings in.
  	 */
  	public void shareStrings(Metadata metadata) {
  		if (metadata == null || metadata.getMetaElements().isEmpty())
  			return;
  
  		final ValidatedMetaMap sourceMap = metadata.metaElements;
  		final ValidatorResolver sourceResolver = sourceMap.getValidatorResolver();
  
  		final ValidatedMetaMap newMap = new ValidatedMetaMap(sourceMap.size(), null);
  		for (Meta meta : sourceMap.valuesWithoutValidation()) {
  			meta.name = toSharedString(meta.name);
  
  			if (includeStringValues && meta.getDataType() == DataType.STRING) {
  				if (meta.value instanceof String)
  					meta.value = toSharedString((String) meta.value);
  				else if (meta.value instanceof String[])
  					toSharedStrings((String[]) meta.value);
  			}
  
  			newMap.put(meta.name, meta);
  		}
  
  		newMap.setValidatorResolver(sourceResolver);
  		metadata.metaElements = newMap;
  	}
  }