Java tutorial
/* * 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.impl; import io.netty.buffer.ByteBuf; import io.netty.buffer.ByteBufUtil; import io.netty.util.Recycler; import io.netty.util.Recycler.Handle; import io.netty.util.ReferenceCountUtil; import java.nio.ByteBuffer; import org.apache.bookkeeper.client.api.LedgerEntry; /** * Ledger entry. Its a simple tuple containing the ledger id, the entry-id, and * the entry content. */ public class LedgerEntryImpl implements LedgerEntry { private static final Recycler<LedgerEntryImpl> RECYCLER = new Recycler<LedgerEntryImpl>() { @Override protected LedgerEntryImpl newObject(Handle<LedgerEntryImpl> handle) { return new LedgerEntryImpl(handle); } }; public static LedgerEntryImpl create(long ledgerId, long entryId) { LedgerEntryImpl entry = RECYCLER.get(); entry.ledgerId = ledgerId; entry.entryId = entryId; return entry; } public static LedgerEntryImpl create(long ledgerId, long entryId, long length, ByteBuf buf) { LedgerEntryImpl entry = RECYCLER.get(); entry.ledgerId = ledgerId; entry.entryId = entryId; entry.length = length; entry.entryBuf = buf; return entry; } public static LedgerEntryImpl duplicate(LedgerEntry entry) { return create(entry.getLedgerId(), entry.getEntryId(), entry.getLength(), entry.getEntryBuffer().retainedSlice()); } private final Handle<LedgerEntryImpl> recycleHandle; private long ledgerId; private long entryId; private long length; private ByteBuf entryBuf; private LedgerEntryImpl(Handle<LedgerEntryImpl> handle) { this.recycleHandle = handle; } public void setEntryId(long entryId) { this.entryId = entryId; } public void setLength(long length) { this.length = length; } public void setEntryBuf(ByteBuf buf) { ReferenceCountUtil.release(entryBuf); this.entryBuf = buf; } /** * {@inheritDoc} */ @Override public long getLedgerId() { return ledgerId; } /** * {@inheritDoc} */ @Override public long getEntryId() { return entryId; } /** * {@inheritDoc} */ @Override public long getLength() { return length; } /** * {@inheritDoc} */ @Override public byte[] getEntryBytes() { return ByteBufUtil.getBytes(entryBuf, entryBuf.readerIndex(), entryBuf.readableBytes(), false); } /** * {@inheritDoc} */ @Override public ByteBuf getEntryBuffer() { return entryBuf; } /** * {@inheritDoc} */ @Override public ByteBuffer getEntryNioBuffer() { return entryBuf.nioBuffer(); } /** * {@inheritDoc} */ @Override public LedgerEntryImpl duplicate() { return duplicate(this); } /** * {@inheritDoc} */ @Override public void close() { recycle(); } private void recycle() { this.ledgerId = -1L; this.entryId = -1L; this.length = -1L; ReferenceCountUtil.release(entryBuf); this.entryBuf = null; recycleHandle.recycle(this); } }