--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lucene/src/luan/modules/lucene/LuceneWriter.java	Tue Sep 30 20:03:56 2014 +0000
@@ -0,0 +1,93 @@
+package luan.modules.lucene;
+
+import java.io.IOException;
+import java.util.Map;
+import java.util.Set;
+import java.util.List;
+import java.util.ArrayList;
+import org.apache.lucene.index.IndexableField;
+import org.apache.lucene.index.Term;
+import luan.Luan;
+import luan.LuanState;
+import luan.LuanTable;
+import luan.LuanJavaFunction;
+import luan.LuanException;
+
+
+public final class LuceneWriter {
+	public static final String FLD_TYPE = "type index";
+	public static final String FLD_ID = "id index";
+
+	private final LuceneIndex index;
+
+	LuceneWriter(LuceneIndex index) {
+		index.writeLock.lock();
+		this.index = index;
+	}
+
+	// call in finally block
+	void close() {
+		index.writeLock.unlock();
+	}
+
+	void commit() throws IOException {
+		index.writer.commit();
+	}
+
+	void addDocument(LuanTable doc) throws IOException {
+		index.writer.addDocument(LuceneDocument.toLucene(doc));
+	}
+
+	void updateDocument(Term term,LuanTable doc) throws IOException {
+		index.writer.updateDocument(term,LuceneDocument.toLucene(doc));
+	}
+
+	public void delete_documents(LuanState luan,LuanTable tblTerms) throws LuanException, IOException {
+		List<Term> list = new ArrayList<Term>();
+		for( Map.Entry<Object,Object> entry : tblTerms ) {
+			Object key = entry.getKey();
+			Object value = entry.getValue();
+			if( !(key instanceof String) )
+				throw luan.exception("key must be a string but got "+key.getClass().getSimpleName());
+			if( !(value instanceof String) )
+				throw luan.exception("value must be a string but got "+value.getClass().getSimpleName());
+			list.add( new Term( (String)key, (String)value ) );
+		}
+		index.writer.deleteDocuments(list.toArray(new Term[list.size()]));
+	}
+
+	String nextId() {
+		return index.nextId();
+	}
+
+	public void save_document(LuanTable doc) throws IOException {
+		if( doc.get(FLD_TYPE)==null )
+			throw new RuntimeException("missing '"+FLD_TYPE+"'");
+		String id = (String)doc.get(FLD_ID);
+		if( id == null ) {
+			id = nextId();
+			doc.put(FLD_ID,id);
+			addDocument(doc);
+		} else {
+			updateDocument(new Term(FLD_ID,id),doc);
+		}
+	}
+
+	// luan
+
+	private void add(LuanTable t,String method,Class<?>... parameterTypes) throws NoSuchMethodException {
+		t.put( method, new LuanJavaFunction(LuceneWriter.class.getMethod(method,parameterTypes),this) );
+	}
+
+	LuanTable table() {
+		LuanTable tbl = Luan.newTable();
+		try {
+			add( tbl, "save_document", LuanTable.class );
+			add( tbl, "delete_documents", LuanState.class, LuanTable.class );
+		} catch(NoSuchMethodException e) {
+			throw new RuntimeException(e);
+		}
+		return tbl;
+	}
+
+}