/*
* 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.util;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.classification.InterfaceStability;
import com.google.common.annotations.VisibleForTesting;
/**
* Extends the basic {@link SimpleByteRange} implementation with position
* support. {@code position} is considered transient, not fundamental to the
* definition of the range, and does not participate in
* {@link #compareTo(ByteRange)}, {@link #hashCode()}, or
* {@link #equals(Object)}. {@code Position} is retained by copy operations.
*/
@InterfaceAudience.Private
@InterfaceStability.Evolving
public abstract class AbstractPositionedByteRange extends AbstractByteRange implements
PositionedByteRange {
/**
* The current index into the range. Like {@link java.nio.ByteBuffer} position, it
* points to the next value that will be read/written in the array. It
* provides the appearance of being 0-indexed, even though its value is
* calculated according to offset.
* <p>
* Position is considered transient and does not participate in
* {@link #equals(Object)} or {@link #hashCode()} comparisons.
* </p>
*/
protected int position = 0;
protected int limit = 0;
@Override
public abstract PositionedByteRange unset();
@Override
public PositionedByteRange set(int capacity) {
this.position = 0;
super.set(capacity);
this.limit = capacity;
return this;
}
@Override
public PositionedByteRange set(byte[] bytes) {
this.position = 0;
super.set(bytes);
this.limit = bytes.length;
return this;
}
@Override
public PositionedByteRange set(byte[] bytes, int offset, int length) {
this.position = 0;
super.set(bytes, offset, length);
limit = length;
return this;
}
/**
* Update the beginning of this range. {@code offset + length} may not be
* greater than {@code bytes.length}. Resets {@code position} to 0.
*
* @param offset
* the new start of this range.
* @return this.
*/
@Override
public PositionedByteRange setOffset(int offset) {
this.position = 0;
super.setOffset(offset);
return this;
}
/**
* Update the length of this range. {@code offset + length} should not be
* greater than {@code bytes.length}. If {@code position} is greater than the
* new {@code length}, sets {@code position} to {@code length}.
*
* @param length
* The new length of this range.
* @return this.
*/
@Override
public PositionedByteRange setLength(int length) {
this.position = Math.min(position, length);
super.setLength(length);
return this;
}
@Override
public int getPosition() {
return position;
}
@Override
public PositionedByteRange setPosition(int position) {
this.position = position;
return this;
}
@Override
public int getRemaining() {
return length - position;
}
@Override
public byte peek() {
return bytes[offset + position];
}
@Override
public byte get() {
return get(position++);
}
@Override
public PositionedByteRange get(byte[] dst) {
if (0 == dst.length)
return this;
return this.get(dst, 0, dst.length); // be clear we're calling self, not
// super
}
@Override
public PositionedByteRange get(byte[] dst, int offset, int length) {
if (0 == length)
return this;
super.get(this.position, dst, offset, length);
this.position += length;
return this;
}
@Override
public abstract PositionedByteRange put(byte val);
@Override
public abstract PositionedByteRange put(byte[] val);
@Override
public abstract PositionedByteRange put(byte[] val, int offset, int length);
@Override
public abstract PositionedByteRange putInt(int index, int val);
@Override
public abstract PositionedByteRange putLong(int index, long val);
@Override
public abstract PositionedByteRange putShort(int index, short val);
@Override
public abstract PositionedByteRange putInt(int val);
@Override
public abstract PositionedByteRange putLong(long val);
@Override
public abstract PositionedByteRange putShort(short val);
@Override
public abstract int putVLong(int index, long val);
@Override
public abstract int putVLong(long val);
/**
* Similar to {@link java.nio.ByteBuffer#flip()}. Sets length to position, position to
* offset.
*/
@VisibleForTesting
PositionedByteRange flip() {
clearHashCache();
length = position;
position = offset;
return this;
}
/**
* Similar to {@link java.nio.ByteBuffer#clear()}. Sets position to 0, length to
* capacity.
*/
@VisibleForTesting
PositionedByteRange clear() {
clearHashCache();
position = 0;
length = bytes.length - offset;
return this;
}
// java boilerplate
@Override
public PositionedByteRange get(int index, byte[] dst) {
super.get(index, dst);
return this;
}
@Override
public PositionedByteRange get(int index, byte[] dst, int offset, int length) {
super.get(index, dst, offset, length);
return this;
}
@Override
public short getShort() {
short s = getShort(position);
position += Bytes.SIZEOF_SHORT;
return s;
}
@Override
public int getInt() {
int i = getInt(position);
position += Bytes.SIZEOF_INT;
return i;
}
@Override
public long getLong() {
long l = getLong(position);
position += Bytes.SIZEOF_LONG;
return l;
}
@Override
public long getVLong() {
long p = getVLong(position);
position += getVLongSize(p);
return p;
}
@Override
public abstract PositionedByteRange put(int index, byte val);
@Override
public abstract PositionedByteRange put(int index, byte[] val);
@Override
public abstract PositionedByteRange put(int index, byte[] val, int offset, int length);
@Override
public abstract PositionedByteRange deepCopy();
@Override
public abstract PositionedByteRange shallowCopy();
@Override
public abstract PositionedByteRange shallowCopySubRange(int innerOffset, int copyLength);
@Override
public PositionedByteRange setLimit(int limit) {
this.limit = limit;
return this;
}
@Override
public int getLimit() {
return this.limit;
}
}