| /* |
| * 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.cassandra.io.util; |
| |
| import java.nio.ByteBuffer; |
| import java.nio.ByteOrder; |
| |
| public class SafeMemoryWriter extends DataOutputBuffer |
| { |
| private SafeMemory memory; |
| |
| @SuppressWarnings("resource") |
| public SafeMemoryWriter(long initialCapacity) |
| { |
| this(new SafeMemory(initialCapacity)); |
| } |
| |
| private SafeMemoryWriter(SafeMemory memory) |
| { |
| super(tailBuffer(memory).order(ByteOrder.BIG_ENDIAN)); |
| this.memory = memory; |
| } |
| |
| public SafeMemory currentBuffer() |
| { |
| return memory; |
| } |
| |
| @Override |
| protected void expandToFit(long count) |
| { |
| resizeTo(calculateNewSize(count)); |
| } |
| |
| private void resizeTo(long newCapacity) |
| { |
| if (newCapacity != capacity()) |
| { |
| long position = length(); |
| ByteOrder order = buffer.order(); |
| |
| SafeMemory oldBuffer = memory; |
| memory = this.memory.copy(newCapacity); |
| buffer = tailBuffer(memory); |
| |
| int newPosition = (int) (position - tailOffset(memory)); |
| buffer.position(newPosition); |
| buffer.order(order); |
| |
| oldBuffer.free(); |
| } |
| } |
| |
| public void trim() |
| { |
| resizeTo(length()); |
| } |
| |
| public void close() |
| { |
| memory.close(); |
| } |
| |
| public Throwable close(Throwable accumulate) |
| { |
| return memory.close(accumulate); |
| } |
| |
| public long length() |
| { |
| return tailOffset(memory) + buffer.position(); |
| } |
| |
| public long capacity() |
| { |
| return memory.size(); |
| } |
| |
| @Override |
| public SafeMemoryWriter order(ByteOrder order) |
| { |
| super.order(order); |
| return this; |
| } |
| |
| @Override |
| public long validateReallocation(long newSize) |
| { |
| // Make sure size does not grow by more than the max buffer size, otherwise we'll hit an exception |
| // when setting up the buffer position. |
| return Math.min(newSize, length() + Integer.MAX_VALUE); |
| } |
| |
| private static long tailOffset(Memory memory) |
| { |
| return Math.max(0, memory.size - Integer.MAX_VALUE); |
| } |
| |
| private static ByteBuffer tailBuffer(Memory memory) |
| { |
| return memory.asByteBuffer(tailOffset(memory), (int) Math.min(memory.size, Integer.MAX_VALUE)); |
| } |
| } |