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 org.apache.hadoop.hbase.Cell; 023import org.apache.hadoop.hbase.CellUtil; 024import org.apache.hadoop.hbase.TableNotEnabledException; 025import org.apache.hadoop.hbase.TableNotFoundException; 026import org.apache.hadoop.hbase.UnknownScannerException; 027import org.apache.hadoop.hbase.client.Result; 028import org.apache.hadoop.hbase.client.ResultScanner; 029import org.apache.hadoop.hbase.client.Scan; 030import org.apache.hadoop.hbase.client.Table; 031import org.apache.hadoop.hbase.filter.Filter; 032import org.apache.hadoop.hbase.rest.model.ScannerModel; 033import org.apache.hadoop.hbase.security.visibility.Authorizations; 034import org.apache.hadoop.hbase.util.EnvironmentEdgeManager; 035import org.apache.hadoop.util.StringUtils; 036import org.apache.yetus.audience.InterfaceAudience; 037import org.slf4j.Logger; 038import org.slf4j.LoggerFactory; 039 040@InterfaceAudience.Private 041public class ScannerResultGenerator extends ResultGenerator { 042 043 private static final Logger LOG = LoggerFactory.getLogger(ScannerResultGenerator.class); 044 045 public static Filter buildFilterFromModel(final ScannerModel model) throws Exception { 046 String filter = model.getFilter(); 047 if (filter == null || filter.length() == 0) { 048 return null; 049 } 050 return buildFilter(filter); 051 } 052 053 private String id; 054 private Iterator<Cell> rowI; 055 private Cell cache; 056 private ResultScanner scanner; 057 private Result cached; 058 059 public ScannerResultGenerator(final String tableName, final RowSpec rowspec, final Filter filter, 060 final boolean cacheBlocks) throws IllegalArgumentException, IOException { 061 this(tableName, rowspec, filter, -1, cacheBlocks); 062 } 063 064 public ScannerResultGenerator(final String tableName, final RowSpec rowspec, final Filter filter, 065 final int caching, final boolean cacheBlocks) throws IllegalArgumentException, IOException { 066 Table table = RESTServlet.getInstance().getTable(tableName); 067 try { 068 Scan scan; 069 if (rowspec.hasEndRow()) { 070 scan = new Scan(rowspec.getStartRow(), rowspec.getEndRow()); 071 } else { 072 scan = new Scan(rowspec.getStartRow()); 073 } 074 if (rowspec.hasColumns()) { 075 byte[][] columns = rowspec.getColumns(); 076 for (byte[] column : columns) { 077 byte[][] split = CellUtil.parseColumn(column); 078 if (split.length == 1) { 079 scan.addFamily(split[0]); 080 } else if (split.length == 2) { 081 scan.addColumn(split[0], split[1]); 082 } else { 083 throw new IllegalArgumentException("Invalid familyAndQualifier provided."); 084 } 085 } 086 } 087 scan.setTimeRange(rowspec.getStartTime(), rowspec.getEndTime()); 088 scan.setMaxVersions(rowspec.getMaxVersions()); 089 if (filter != null) { 090 scan.setFilter(filter); 091 } 092 if (caching > 0) { 093 scan.setCaching(caching); 094 } 095 scan.setCacheBlocks(cacheBlocks); 096 if (rowspec.hasLabels()) { 097 scan.setAuthorizations(new Authorizations(rowspec.getLabels())); 098 } 099 scanner = table.getScanner(scan); 100 cached = null; 101 id = Long.toString(EnvironmentEdgeManager.currentTime()) 102 + Integer.toHexString(scanner.hashCode()); 103 } finally { 104 table.close(); 105 } 106 } 107 108 public String getID() { 109 return id; 110 } 111 112 @Override 113 public void close() { 114 if (scanner != null) { 115 scanner.close(); 116 scanner = null; 117 } 118 } 119 120 @Override 121 public boolean hasNext() { 122 if (cache != null) { 123 return true; 124 } 125 if (rowI != null && rowI.hasNext()) { 126 return true; 127 } 128 if (cached != null) { 129 return true; 130 } 131 try { 132 Result result = scanner.next(); 133 if (result != null && !result.isEmpty()) { 134 cached = result; 135 } 136 } catch (UnknownScannerException e) { 137 throw new IllegalArgumentException(e); 138 } catch (IOException e) { 139 LOG.error(StringUtils.stringifyException(e)); 140 } 141 return cached != null; 142 } 143 144 @Override 145 public Cell next() { 146 if (cache != null) { 147 Cell kv = cache; 148 cache = null; 149 return kv; 150 } 151 boolean loop; 152 do { 153 loop = false; 154 if (rowI != null) { 155 if (rowI.hasNext()) { 156 return rowI.next(); 157 } else { 158 rowI = null; 159 } 160 } 161 if (cached != null) { 162 rowI = cached.listCells().iterator(); 163 loop = true; 164 cached = null; 165 } else { 166 Result result = null; 167 try { 168 result = scanner.next(); 169 } catch (UnknownScannerException e) { 170 throw new IllegalArgumentException(e); 171 } catch (TableNotEnabledException tnee) { 172 throw new IllegalStateException(tnee); 173 } catch (TableNotFoundException tnfe) { 174 throw new IllegalArgumentException(tnfe); 175 } catch (IOException e) { 176 LOG.error(StringUtils.stringifyException(e)); 177 } 178 if (result != null && !result.isEmpty()) { 179 rowI = result.listCells().iterator(); 180 loop = true; 181 } 182 } 183 } while (loop); 184 return null; 185 } 186 187 @Override 188 public void putBack(Cell kv) { 189 this.cache = kv; 190 } 191 192 @Override 193 public void remove() { 194 throw new UnsupportedOperationException("remove not supported"); 195 } 196}