| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.oodt.cas.catalog.struct; |
| |
| //OODT imports |
| import org.apache.oodt.cas.catalog.exception.CatalogDictionaryException; |
| import org.apache.oodt.cas.catalog.query.QueryExpression; |
| import org.apache.oodt.cas.catalog.term.TermBucket; |
| import org.apache.oodt.cas.metadata.Metadata; |
| |
| /** |
| * @author bfoster |
| * @version $Revision$ |
| * |
| * <p> |
| * A Dictionary for create Catalog understandable Terms from Metadata |
| * <p> |
| */ |
| public interface Dictionary { |
| |
| /** |
| * Given a Metadata object a lookup call to a given dictionary will |
| * always return the same TermBucket. However, calls to several |
| * Dictionary's lookup method may return different TermBuckets for |
| * a given Metadata object. |
| * @param metadata The Metadata for which a TermBucket will be created |
| * @return TermBucket representing the given Metadata for this Dictionary or |
| * null if Metadata is not recognized by this Dictionary |
| */ |
| public TermBucket lookup(Metadata metadata) throws CatalogDictionaryException; |
| |
| /** |
| * Generates Metadata for the given TermBucket. A call to lookup(Metadata) and |
| * then reverseLookup(TermBucket) may not give you back the original Metadata |
| * because lookup may ignore key/values in Metadata for which it does not |
| * understand. |
| * @param termBucket The TermBucket for which Metadata will be created |
| * @return Metadata for the given TermBucket. If the TermBucket is not understood, |
| * then an empty Metadata object should be returned. |
| */ |
| public Metadata reverseLookup(TermBucket termBucket) throws CatalogDictionaryException; |
| |
| /** |
| * |
| * @param queryExpression |
| * @return |
| * @throws CatalogDictionaryException |
| */ |
| public boolean understands(QueryExpression queryExpression) throws CatalogDictionaryException; |
| |
| } |