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Java project to access the HCL Domino C API using Java Native Access (JNA)

There is a newer version: 0.9.53

package com.mindoo.domino.jna.internal;

import com.mindoo.domino.jna.utils.LMBCSString;
import com.mindoo.domino.jna.utils.NotesStringUtils;

/**
 * Cache to optimize performance of LMBCS String conversion to Java Strings.
 * 
 * @author Karsten Lehmann
 */
public class LMBCSStringConversionCache {
	//use simple cache for lmbcs-string conversion of short string
	private static final boolean USE_LMBCS2STRING_CACHE = true;
	//max length of each lmbcs-string cache entry in bytes
	private static final int MAX_LMBCS2STRING_KEY_LENGTH = 1000;

	private static final int MAX_LMBCS2STRING_SIZE_BYTES = 1000000;

	private static SizeLimitedLRUCache LMBCS2STRINGCACHE = new SizeLimitedLRUCache(MAX_LMBCS2STRING_SIZE_BYTES) {
		@Override
		protected int computeSize(LMBCSString key, String value) {
			return key.size() + value.length()*2;
		}
	};

	public static long getCacheSize() {
		return LMBCS2STRINGCACHE.getCurrentCacheSizeInUnits();
	}

	/**
	 * Converts an LMBCS string to a Java String. If already cached, no native call is made.
	 * 
	 * @param lmbcsString LMBCS string
	 * @return converted string
	 */
	public static String get(LMBCSString lmbcsString) {
		String stringFromCache = LMBCS2STRINGCACHE.get(lmbcsString);
		String convertedString;
		
		if (stringFromCache==null) {
			byte[] dataArr = lmbcsString.getData();
			
			convertedString = NotesStringUtils.fromLMBCS(dataArr);
			if (USE_LMBCS2STRING_CACHE && lmbcsString.size()<=MAX_LMBCS2STRING_KEY_LENGTH) {
				LMBCS2STRINGCACHE.put(lmbcsString, convertedString);
			}
		}
		else {
			convertedString = stringFromCache;
		}
		return convertedString;
	}
}