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.types;
019
020import org.apache.hadoop.hbase.util.Bytes;
021import org.apache.hadoop.hbase.util.Order;
022import org.apache.hadoop.hbase.util.PositionedByteRange;
023import org.apache.yetus.audience.InterfaceAudience;
024
025/**
026 * An {@code DataType} for interacting with values encoded using {@link Bytes#toBytes(String)}.
027 * Intended to make it easier to transition away from direct use of {@link Bytes}.
028 * @see Bytes#toBytes(String)
029 * @see Bytes#toString(byte[])
030 * @see RawStringTerminated
031 */
032@InterfaceAudience.Public
033public class RawString implements DataType<String> {
034
035  public static final RawString ASCENDING = new RawString(Order.ASCENDING);
036  public static final RawString DESCENDING = new RawString(Order.DESCENDING);
037
038  protected final Order order;
039
040  protected RawString() {
041    this.order = Order.ASCENDING;
042  }
043
044  protected RawString(Order order) {
045    this.order = order;
046  }
047
048  @Override
049  public boolean isOrderPreserving() {
050    return true;
051  }
052
053  @Override
054  public Order getOrder() {
055    return order;
056  }
057
058  @Override
059  public boolean isNullable() {
060    return false;
061  }
062
063  @Override
064  public boolean isSkippable() {
065    return false;
066  }
067
068  @Override
069  public int skip(PositionedByteRange src) {
070    int skipped = src.getRemaining();
071    src.setPosition(src.getLength());
072    return skipped;
073  }
074
075  @Override
076  public int encodedLength(String val) {
077    return Bytes.toBytes(val).length;
078  }
079
080  @Override
081  public Class<String> encodedClass() {
082    return String.class;
083  }
084
085  @Override
086  public String decode(PositionedByteRange src) {
087    if (Order.ASCENDING == this.order) {
088      // avoid unnecessary array copy for ASC case.
089      String val =
090        Bytes.toString(src.getBytes(), src.getOffset() + src.getPosition(), src.getRemaining());
091      src.setPosition(src.getLength());
092      return val;
093    } else {
094      byte[] b = new byte[src.getRemaining()];
095      src.get(b);
096      order.apply(b, 0, b.length);
097      return Bytes.toString(b);
098    }
099  }
100
101  @Override
102  public int encode(PositionedByteRange dst, String val) {
103    byte[] s = Bytes.toBytes(val);
104    order.apply(s);
105    dst.put(s);
106    return s.length;
107  }
108}