| /* |
| * Copyright 2010 The Apache Software Foundation |
| * |
| * 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.hadoop.hbase.rest; |
| |
| import java.io.IOException; |
| import java.util.Iterator; |
| import java.util.NoSuchElementException; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| |
| import org.apache.hadoop.util.StringUtils; |
| import org.apache.hadoop.hbase.HColumnDescriptor; |
| import org.apache.hadoop.hbase.KeyValue; |
| import org.apache.hadoop.hbase.client.Get; |
| import org.apache.hadoop.hbase.client.HTableInterface; |
| import org.apache.hadoop.hbase.client.HTablePool; |
| import org.apache.hadoop.hbase.client.Result; |
| import org.apache.hadoop.hbase.filter.Filter; |
| import org.apache.hadoop.hbase.regionserver.NoSuchColumnFamilyException; |
| |
| public class RowResultGenerator extends ResultGenerator { |
| private static final Log LOG = LogFactory.getLog(RowResultGenerator.class); |
| |
| private Iterator<KeyValue> valuesI; |
| private KeyValue cache; |
| |
| public RowResultGenerator(final String tableName, final RowSpec rowspec, |
| final Filter filter) throws IllegalArgumentException, IOException { |
| HTablePool pool = RESTServlet.getInstance().getTablePool(); |
| HTableInterface table = pool.getTable(tableName); |
| try { |
| Get get = new Get(rowspec.getRow()); |
| if (rowspec.hasColumns()) { |
| for (byte[] col: rowspec.getColumns()) { |
| byte[][] split = KeyValue.parseColumn(col); |
| if (split.length == 2 && split[1].length != 0) { |
| get.addColumn(split[0], split[1]); |
| } else { |
| get.addFamily(split[0]); |
| } |
| } |
| } else { |
| // rowspec does not explicitly specify columns, return them all |
| for (HColumnDescriptor family: |
| table.getTableDescriptor().getFamilies()) { |
| get.addFamily(family.getName()); |
| } |
| } |
| get.setTimeRange(rowspec.getStartTime(), rowspec.getEndTime()); |
| get.setMaxVersions(rowspec.getMaxVersions()); |
| if (filter != null) { |
| get.setFilter(filter); |
| } |
| Result result = table.get(get); |
| if (result != null && !result.isEmpty()) { |
| valuesI = result.list().iterator(); |
| } |
| } catch (NoSuchColumnFamilyException e) { |
| // Warn here because Stargate will return 404 in the case if multiple |
| // column families were specified but one did not exist -- currently |
| // HBase will fail the whole Get. |
| // Specifying multiple columns in a URI should be uncommon usage but |
| // help to avoid confusion by leaving a record of what happened here in |
| // the log. |
| LOG.warn(StringUtils.stringifyException(e)); |
| } finally { |
| pool.putTable(table); |
| } |
| } |
| |
| public void close() { |
| } |
| |
| public boolean hasNext() { |
| if (cache != null) { |
| return true; |
| } |
| if (valuesI == null) { |
| return false; |
| } |
| return valuesI.hasNext(); |
| } |
| |
| public KeyValue next() { |
| if (cache != null) { |
| KeyValue kv = cache; |
| cache = null; |
| return kv; |
| } |
| if (valuesI == null) { |
| return null; |
| } |
| try { |
| return valuesI.next(); |
| } catch (NoSuchElementException e) { |
| return null; |
| } |
| } |
| |
| public void putBack(KeyValue kv) { |
| this.cache = kv; |
| } |
| |
| public void remove() { |
| throw new UnsupportedOperationException("remove not supported"); |
| } |
| } |