| /* ==================================================================== |
| 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.poi.hssf.record.cont; |
| |
| import org.apache.poi.hssf.record.RecordInputStream; |
| import org.apache.poi.util.DelayableLittleEndianOutput; |
| import org.apache.poi.util.LittleEndianByteArrayOutputStream; |
| import org.apache.poi.util.LittleEndianOutput; |
| /** |
| * Allows the writing of BIFF records when the 'ushort size' header field is not known in advance. |
| * When the client is finished writing data, it calls {@link #terminate()}, at which point this |
| * class updates the 'ushort size' with its final value. |
| */ |
| final class UnknownLengthRecordOutput implements LittleEndianOutput { |
| private static final int MAX_DATA_SIZE = RecordInputStream.MAX_RECORD_DATA_SIZE; |
| |
| private final LittleEndianOutput _originalOut; |
| /** for writing the 'ushort size' field once its value is known */ |
| private final LittleEndianOutput _dataSizeOutput; |
| private final byte[] _byteBuffer; |
| private LittleEndianOutput _out; |
| private int _size; |
| |
| public UnknownLengthRecordOutput(LittleEndianOutput out, int sid) { |
| _originalOut = out; |
| out.writeShort(sid); |
| if (out instanceof DelayableLittleEndianOutput) { |
| // optimisation |
| DelayableLittleEndianOutput dleo = (DelayableLittleEndianOutput) out; |
| _dataSizeOutput = dleo.createDelayedOutput(2); |
| _byteBuffer = null; |
| _out = out; |
| } else { |
| // otherwise temporarily write all subsequent data to a buffer |
| _dataSizeOutput = out; |
| _byteBuffer = new byte[RecordInputStream.MAX_RECORD_DATA_SIZE]; |
| _out = new LittleEndianByteArrayOutputStream(_byteBuffer, 0); |
| } |
| } |
| /** |
| * includes 4 byte header |
| */ |
| public int getTotalSize() { |
| return 4 + _size; |
| } |
| public int getAvailableSpace() { |
| if (_out == null) { |
| throw new IllegalStateException("Record already terminated"); |
| } |
| return MAX_DATA_SIZE - _size; |
| } |
| /** |
| * Finishes writing the current record and updates 'ushort size' field.<br/> |
| * After this method is called, only {@link #getTotalSize()} may be called. |
| */ |
| public void terminate() { |
| if (_out == null) { |
| throw new IllegalStateException("Record already terminated"); |
| } |
| _dataSizeOutput.writeShort(_size); |
| if (_byteBuffer != null) { |
| _originalOut.write(_byteBuffer, 0, _size); |
| _out = null; |
| return; |
| } |
| _out = null; |
| } |
| |
| public void write(byte[] b) { |
| _out.write(b); |
| _size += b.length; |
| } |
| public void write(byte[] b, int offset, int len) { |
| _out.write(b, offset, len); |
| _size += len; |
| } |
| public void writeByte(int v) { |
| _out.writeByte(v); |
| _size += 1; |
| } |
| public void writeDouble(double v) { |
| _out.writeDouble(v); |
| _size += 8; |
| } |
| public void writeInt(int v) { |
| _out.writeInt(v); |
| _size += 4; |
| } |
| public void writeLong(long v) { |
| _out.writeLong(v); |
| _size += 8; |
| } |
| public void writeShort(int v) { |
| _out.writeShort(v); |
| _size += 2; |
| } |
| } |