package edu.isi.karma.kr2rml.writer;
import java.io.IOException;
import java.nio.charset.Charset;
import java.util.Map.Entry;
import java.util.concurrent.ConcurrentHashMap;
import org.apache.hadoop.util.bloom.Key;
import org.apache.hadoop.util.hash.Hash;
import org.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import edu.isi.karma.kr2rml.mapping.R2RMLMappingIdentifier;
import edu.isi.karma.modeling.Uris;
public class KR2RMLBloomFilterManager {
private static final Logger LOG = LoggerFactory.getLogger(KR2RMLBloomFilterManager.class);
private static final Charset UTF8_CHARSET = Charset.forName("UTF-8");
protected ConcurrentHashMap<String, KR2RMLBloomFilter> idToBloomFilter;
protected R2RMLMappingIdentifier mappingIdentifier;
public KR2RMLBloomFilterManager(R2RMLMappingIdentifier mappingIdentifier)
{
idToBloomFilter = new ConcurrentHashMap<String, KR2RMLBloomFilter>();
this.mappingIdentifier = mappingIdentifier;
}
public KR2RMLBloomFilterManager(JSONObject serializedManager) throws IOException
{
idToBloomFilter = new ConcurrentHashMap<String, KR2RMLBloomFilter>();
String idsConcatenated = serializedManager.getString("ids");
String[] ids = idsConcatenated.split(",");
for(String id : ids)
{
String base64EncodedBloomFilter = serializedManager.getString(id);
KR2RMLBloomFilter bf = new KR2RMLBloomFilter();
bf.populateFromCompressedAndBase64EncodedString(base64EncodedBloomFilter);
idToBloomFilter.put(id, bf);
}
this.mappingIdentifier = new R2RMLMappingIdentifier(serializedManager.getJSONObject("mappingIdentifier"));
}
public KR2RMLBloomFilter getBloomFilter(String id)
{
return idToBloomFilter.get(id);
}
public void addUriToBloomFilter(String id, String uri) {
KR2RMLBloomFilter bf = null;
if(!idToBloomFilter.containsKey(id))
{
idToBloomFilter.putIfAbsent(id, new KR2RMLBloomFilter(KR2RMLBloomFilter.defaultVectorSize, KR2RMLBloomFilter.defaultnbHash, Hash.JENKINS_HASH));
}
bf = idToBloomFilter.get(id);
Key k = new Key(uri.getBytes(UTF8_CHARSET));
bf.add(k);
return;
}
public JSONObject toJSON()
{
JSONObject filters = new JSONObject();
StringBuffer ids = new StringBuffer();
for(Entry<String, KR2RMLBloomFilter> entry : idToBloomFilter.entrySet())
{
String key = entry.getKey();
KR2RMLBloomFilter bf = entry.getValue();
try
{
String base64EncodedCompressedSerializedBloomFilter = bf.compressAndBase64Encode();
filters.put(key, base64EncodedCompressedSerializedBloomFilter);
}
catch (IOException e)
{
LOG.error("Unable to append bloom filter for id: " +key);
continue;
}
if(ids.length() != 0)
{
ids.append(",");
}
ids.append(entry.getKey());
}
filters.put("ids", ids.toString());
filters.put("mappingIdentifier", mappingIdentifier.toJSON());
return filters;
}
public String toRDF()
{
StringBuilder builder = new StringBuilder();
for(Entry<String, KR2RMLBloomFilter> entry : idToBloomFilter.entrySet())
{
KR2RMLBloomFilter bf = entry.getValue();
String key = entry.getKey();
StringBuilder tripleBuilder = new StringBuilder();
tripleBuilder.append("<");
tripleBuilder.append(key);
tripleBuilder.append("> <");
tripleBuilder.append(Uris.KM_HAS_BLOOMFILTER);
tripleBuilder.append("> \"");
try
{
String base64EncodedCompressedSerializedBloomFilter = bf.compressAndBase64Encode();
tripleBuilder.append(base64EncodedCompressedSerializedBloomFilter);
}
catch (IOException e)
{
LOG.error("Unable to append bloom filter for id: " + key);
continue;
}
tripleBuilder.append("\" . \n");
builder.append(tripleBuilder);
}
return builder.toString();
}
}