001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018package org.apache.hadoop.hbase.rest; 019 020import java.io.IOException; 021import java.util.Iterator; 022import java.util.NoSuchElementException; 023import org.apache.hadoop.hbase.Cell; 024import org.apache.hadoop.hbase.CellUtil; 025import org.apache.hadoop.hbase.DoNotRetryIOException; 026import org.apache.hadoop.hbase.client.Get; 027import org.apache.hadoop.hbase.client.Result; 028import org.apache.hadoop.hbase.client.Table; 029import org.apache.hadoop.hbase.filter.Filter; 030import org.apache.hadoop.hbase.security.AccessDeniedException; 031import org.apache.hadoop.util.StringUtils; 032import org.apache.yetus.audience.InterfaceAudience; 033import org.slf4j.Logger; 034import org.slf4j.LoggerFactory; 035 036@InterfaceAudience.Private 037public class RowResultGenerator extends ResultGenerator { 038 private static final Logger LOG = LoggerFactory.getLogger(RowResultGenerator.class); 039 040 private Iterator<Cell> valuesI; 041 private Cell cache; 042 043 public RowResultGenerator(final String tableName, final RowSpec rowspec, final Filter filter, 044 final boolean cacheBlocks) throws IllegalArgumentException, IOException { 045 try (Table table = RESTServlet.getInstance().getTable(tableName)) { 046 Get get = new Get(rowspec.getRow()); 047 if (rowspec.hasColumns()) { 048 for (byte[] col : rowspec.getColumns()) { 049 byte[][] split = CellUtil.parseColumn(col); 050 if (split.length == 1) { 051 get.addFamily(split[0]); 052 } else if (split.length == 2) { 053 get.addColumn(split[0], split[1]); 054 } else { 055 throw new IllegalArgumentException("Invalid column specifier."); 056 } 057 } 058 } 059 if (rowspec.isPartialTimeRange()) { 060 get.setTimestamp(rowspec.getTimestamp()); 061 } else { 062 get.setTimeRange(rowspec.getStartTime(), rowspec.getEndTime()); 063 } 064 065 get.readVersions(rowspec.getMaxVersions()); 066 if (filter != null) { 067 get.setFilter(filter); 068 } 069 get.setCacheBlocks(cacheBlocks); 070 Result result = table.get(get); 071 if (result != null && !result.isEmpty()) { 072 valuesI = result.listCells().iterator(); 073 } 074 } catch (DoNotRetryIOException e) { 075 // Warn here because Stargate will return 404 in the case if multiple 076 // column families were specified but one did not exist -- currently 077 // HBase will fail the whole Get. 078 // Specifying multiple columns in a URI should be uncommon usage but 079 // help to avoid confusion by leaving a record of what happened here in 080 // the log. 081 LOG.warn(StringUtils.stringifyException(e)); 082 // Lets get the exception rethrown to get a more meaningful error message than 404 083 if (e instanceof AccessDeniedException) { 084 throw e; 085 } 086 } 087 } 088 089 @Override 090 public void close() { 091 } 092 093 @Override 094 public boolean hasNext() { 095 if (cache != null) { 096 return true; 097 } 098 if (valuesI == null) { 099 return false; 100 } 101 return valuesI.hasNext(); 102 } 103 104 @Override 105 public Cell next() { 106 if (cache != null) { 107 Cell kv = cache; 108 cache = null; 109 return kv; 110 } 111 if (valuesI == null) { 112 return null; 113 } 114 try { 115 return valuesI.next(); 116 } catch (NoSuchElementException e) { 117 return null; 118 } 119 } 120 121 @Override 122 public void putBack(Cell kv) { 123 this.cache = kv; 124 } 125 126 @Override 127 public void remove() { 128 throw new UnsupportedOperationException("remove not supported"); 129 } 130}