| /* |
| * 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.rya.accumulo; |
| |
| import java.io.IOError; |
| import java.nio.charset.StandardCharsets; |
| import java.util.Iterator; |
| import java.util.Map.Entry; |
| |
| import com.google.common.base.Preconditions; |
| import org.apache.accumulo.core.data.Key; |
| import org.apache.accumulo.core.data.Value; |
| import org.apache.rya.api.persist.RdfDAOException; |
| import org.eclipse.rdf4j.common.iteration.CloseableIteration; |
| import org.eclipse.rdf4j.model.Namespace; |
| import org.eclipse.rdf4j.model.impl.NamespaceImpl; |
| |
| public class AccumuloNamespaceTableIterator<T extends Namespace> implements |
| CloseableIteration<Namespace, RdfDAOException> { |
| |
| private boolean open = false; |
| private final Iterator<Entry<Key, Value>> result; |
| |
| public AccumuloNamespaceTableIterator(final Iterator<Entry<Key, Value>> result) throws RdfDAOException { |
| Preconditions.checkNotNull(result); |
| open = true; |
| this.result = result; |
| } |
| |
| @Override |
| public void close() throws RdfDAOException { |
| try { |
| verifyIsOpen(); |
| open = false; |
| } catch (final IOError e) { |
| throw new RdfDAOException(e); |
| } |
| } |
| |
| public void verifyIsOpen() throws RdfDAOException { |
| if (!open) { |
| throw new RdfDAOException("Iterator not open"); |
| } |
| } |
| |
| @Override |
| public boolean hasNext() throws RdfDAOException { |
| verifyIsOpen(); |
| return result != null && result.hasNext(); |
| } |
| |
| @Override |
| public Namespace next() throws RdfDAOException { |
| if (hasNext()) { |
| return getNamespace(result); |
| } |
| return null; |
| } |
| |
| public static Namespace getNamespace(final Iterator<Entry<Key, Value>> rowResults) { |
| for (; rowResults.hasNext(); ) { |
| final Entry<Key, Value> next = rowResults.next(); |
| final Key key = next.getKey(); |
| final Value val = next.getValue(); |
| final String cf = key.getColumnFamily().toString(); |
| final String cq = key.getColumnQualifier().toString(); |
| return new NamespaceImpl(key.getRow().toString(), |
| new String(val.get(), StandardCharsets.UTF_8)); |
| } |
| return null; |
| } |
| |
| @Override |
| public void remove() throws RdfDAOException { |
| next(); |
| } |
| |
| public boolean isOpen() { |
| return open; |
| } |
| } |