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- /* ====================================================================
- 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.util;
-
- import java.io.OutputStream;
-
- /**
- * Adapts a plain byte array to {@link LittleEndianOutput}
- */
- public final class LittleEndianByteArrayOutputStream extends OutputStream implements LittleEndianOutput, DelayableLittleEndianOutput {
- private final byte[] _buf;
- private final int _endIndex;
- private int _writeIndex;
-
- public LittleEndianByteArrayOutputStream(byte[] buf, int startOffset, int maxWriteLen) { // NOSONAR
- if (startOffset < 0 || startOffset > buf.length) {
- throw new IllegalArgumentException("Specified startOffset (" + startOffset
- + ") is out of allowable range (0.." + buf.length + ")");
- }
- _buf = buf;
- _writeIndex = startOffset;
- _endIndex = startOffset + maxWriteLen;
- if (_endIndex < startOffset || _endIndex > buf.length) {
- throw new IllegalArgumentException("calculated end index (" + _endIndex
- + ") is out of allowable range (" + _writeIndex + ".." + buf.length + ")");
- }
- }
- public LittleEndianByteArrayOutputStream(byte[] buf, int startOffset) {
- this(buf, startOffset, buf.length - startOffset);
- }
-
- private void checkPosition(int i) {
- if (i > _endIndex - _writeIndex) {
- throw new RuntimeException("Buffer overrun");
- }
- }
-
- @Override
- public void writeByte(int v) {
- checkPosition(1);
- _buf[_writeIndex++] = (byte)v;
- }
-
- @Override
- public void writeDouble(double v) {
- writeLong(Double.doubleToLongBits(v));
- }
-
- @Override
- public void writeInt(int v) {
- checkPosition(4);
- int i = _writeIndex;
- _buf[i++] = (byte)((v >>> 0) & 0xFF);
- _buf[i++] = (byte)((v >>> 8) & 0xFF);
- _buf[i++] = (byte)((v >>> 16) & 0xFF);
- _buf[i++] = (byte)((v >>> 24) & 0xFF);
- _writeIndex = i;
- }
-
- @Override
- public void writeLong(long v) {
- writeInt((int)(v >> 0));
- writeInt((int)(v >> 32));
- }
-
- @Override
- public void writeShort(int v) {
- checkPosition(2);
- int i = _writeIndex;
- _buf[i++] = (byte)((v >>> 0) & 0xFF);
- _buf[i++] = (byte)((v >>> 8) & 0xFF);
- _writeIndex = i;
- }
-
- @Override
- public void write(int b) {
- writeByte(b);
- }
-
- @Override
- public void write(byte[] b) {
- int len = b.length;
- checkPosition(len);
- System.arraycopy(b, 0, _buf, _writeIndex, len);
- _writeIndex += len;
- }
-
- @Override
- public void write(byte[] b, int offset, int len) {
- checkPosition(len);
- System.arraycopy(b, offset, _buf, _writeIndex, len);
- _writeIndex += len;
- }
-
- public int getWriteIndex() {
- return _writeIndex;
- }
-
- @Override
- public LittleEndianOutput createDelayedOutput(int size) {
- checkPosition(size);
- LittleEndianOutput result = new LittleEndianByteArrayOutputStream(_buf, _writeIndex, size);
- _writeIndex += size;
- return result;
- }
- }
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