/**
* Copyright (C) 2011 the original author or authors.
* See the notice.md file distributed with this work for additional
* information regarding copyright ownership.
*
* Licensed 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.iq80.leveldb.table;
import com.google.common.base.Preconditions;
import org.iq80.leveldb.CompressionType;
import org.iq80.leveldb.util.SliceInput;
import org.iq80.leveldb.util.Slice;
import org.iq80.leveldb.util.Slices;
import org.iq80.leveldb.util.SliceOutput;
public class BlockTrailer
{
public static final int ENCODED_LENGTH = 5;
private final CompressionType compressionType;
private final int crc32c;
public BlockTrailer(CompressionType compressionType, int crc32c)
{
Preconditions.checkNotNull(compressionType, "compressionType is null");
this.compressionType = compressionType;
this.crc32c = crc32c;
}
public CompressionType getCompressionType()
{
return compressionType;
}
public int getCrc32c()
{
return crc32c;
}
@Override
public boolean equals(Object o)
{
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
BlockTrailer that = (BlockTrailer) o;
if (crc32c != that.crc32c) {
return false;
}
if (compressionType != that.compressionType) {
return false;
}
return true;
}
@Override
public int hashCode()
{
int result = compressionType.hashCode();
result = 31 * result + crc32c;
return result;
}
@Override
public String toString()
{
final StringBuilder sb = new StringBuilder();
sb.append("BlockTrailer");
sb.append("{compressionType=").append(compressionType);
sb.append(", crc32c=0x").append(Integer.toHexString(crc32c));
sb.append('}');
return sb.toString();
}
public static BlockTrailer readBlockTrailer(Slice slice)
{
SliceInput sliceInput = slice.input();
CompressionType compressionType = CompressionType.getCompressionTypeByPersistentId(sliceInput.readUnsignedByte());
int crc32c = sliceInput.readInt();
return new BlockTrailer(compressionType, crc32c);
}
public static Slice writeBlockTrailer(BlockTrailer blockTrailer)
{
Slice slice = Slices.allocate(ENCODED_LENGTH);
writeBlockTrailer(blockTrailer, slice.output());
return slice;
}
public static void writeBlockTrailer(BlockTrailer blockTrailer, SliceOutput sliceOutput)
{
sliceOutput.writeByte(blockTrailer.getCompressionType().persistentId());
sliceOutput.writeInt(blockTrailer.getCrc32c());
}
}