org.apache.bookkeeper.client.LedgerEntry Maven / Gradle / Ivy
/*
*
* 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.bookkeeper.client;
import static com.google.common.base.Preconditions.checkState;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufInputStream;
import java.io.InputStream;
import org.apache.bookkeeper.client.impl.LedgerEntryImpl;
import org.apache.bookkeeper.conf.ClientConfiguration;
/**
* Ledger entry. Its a simple tuple containing the ledger id, the entry-id, and
* the entry content.
*
*/
public class LedgerEntry {
final long ledgerId;
final long entryId;
final long length;
ByteBuf data;
LedgerEntry(LedgerEntryImpl entry) {
this.ledgerId = entry.getLedgerId();
this.entryId = entry.getEntryId();
this.length = entry.getLength();
this.data = entry.getEntryBuffer().retain();
}
public long getLedgerId() {
return ledgerId;
}
public long getEntryId() {
return entryId;
}
public long getLength() {
return length;
}
/**
* Returns the content of the entry.
* This method can be called only once. While using v2 wire protocol this method will automatically release
* the internal ByteBuf
*
* @return the content of the entry
* @throws IllegalStateException if this method is called twice
*/
public byte[] getEntry() {
checkState(null != data, "entry content can be accessed only once");
byte[] entry = new byte[data.readableBytes()];
data.readBytes(entry);
data.release();
data = null;
return entry;
}
/**
* Returns the content of the entry.
* This method can be called only once. While using v2 wire protocol this method will automatically release
* the internal ByteBuf when calling the close
* method of the returned InputStream
*
* @return an InputStream which gives access to the content of the entry
* @throws IllegalStateException if this method is called twice
*/
public InputStream getEntryInputStream() {
checkState(null != data, "entry content can be accessed only once");
ByteBufInputStream res = new ByteBufInputStream(data);
data = null;
return res;
}
/**
* Return the internal buffer that contains the entry payload.
*
* Note: Using v2 wire protocol it is responsibility of the caller to ensure to release the buffer after usage.
*
* @return a ByteBuf which contains the data
*
* @see ClientConfiguration#setNettyUsePooledBuffers(boolean)
* @throws IllegalStateException if the entry has been retrieved by {@link #getEntry()}
* or {@link #getEntryInputStream()}.
*/
public ByteBuf getEntryBuffer() {
checkState(null != data, "entry content has been retrieved by #getEntry or #getEntryInputStream");
return data;
}
}