766 lines
22 KiB
Java
766 lines
22 KiB
Java
/* ====================================================================
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Licensed to the Apache Software Foundation (ASF) under one or more
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contributor license agreements. See the NOTICE file distributed with
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this work for additional information regarding copyright ownership.
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The ASF licenses this file to You under the Apache License, Version 2.0
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(the "License"); you may not use this file except in compliance with
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the License. You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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==================================================================== */
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package org.apache.poi.util;
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import java.io.IOException;
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import java.io.InputStream;
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import java.io.OutputStream;
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import java.io.Serializable;
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/**
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* a utility class for handling little-endian numbers, which the 80x86 world is
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* replete with. The methods are all static, and input/output is from/to byte
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* arrays, or from InputStreams.
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*
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* @author Marc Johnson (mjohnson at apache dot org)
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* @author Andrew Oliver (acoliver at apache dot org)
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*/
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public class LittleEndian implements LittleEndianConsts
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{
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/**
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* Exception to handle buffer underruns
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*
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* @author Marc Johnson (mjohnson at apache dot org)
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*/
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public static final class BufferUnderrunException extends IOException
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{
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/**
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* Serial version UID
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*
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* @see Serializable
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*/
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private static final long serialVersionUID = 8736973884877006145L;
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BufferUnderrunException()
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{
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super( "buffer underrun" );
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}
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}
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/**
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* Copy a portion of a byte array
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*
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* @param data
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* the original byte array
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* @param offset
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* Where to start copying from.
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* @param size
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* Number of bytes to copy.
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* @return The byteArray value
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* @throws IndexOutOfBoundsException
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* - if copying would cause access of data outside array bounds.
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*/
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public static byte[] getByteArray( byte[] data, int offset, int size )
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{
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byte[] copy = new byte[size];
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System.arraycopy( data, offset, copy, 0, size );
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return copy;
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}
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/**
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* get a double value from a byte array, reads it in little endian format
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* then converts the resulting revolting IEEE 754 (curse them) floating
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* point number to a happy java double
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*
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* @param data
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* the byte array
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* @return the double (64-bit) value
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*/
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public static double getDouble( byte[] data )
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{
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return Double.longBitsToDouble( getLong( data, 0 ) );
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}
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/**
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* get a double value from a byte array, reads it in little endian format
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* then converts the resulting revolting IEEE 754 (curse them) floating
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* point number to a happy java double
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*
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* @param data
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* the byte array
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* @param offset
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* a starting offset into the byte array
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* @return the double (64-bit) value
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*/
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public static double getDouble( byte[] data, int offset )
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{
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return Double.longBitsToDouble( getLong( data, offset ) );
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}
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/**
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* get a float value from a byte array, reads it in little endian format
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* then converts the resulting revolting IEEE 754 (curse them) floating
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* point number to a happy java float
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*
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* @param data
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* the byte array
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* @return the double (64-bit) value
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*/
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public static float getFloat( byte[] data )
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{
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return getFloat( data, 0 );
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}
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/**
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* get a float value from a byte array, reads it in little endian format
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* then converts the resulting revolting IEEE 754 (curse them) floating
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* point number to a happy java float
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*
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* @param data
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* the byte array
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* @param offset
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* a starting offset into the byte array
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* @return the double (64-bit) value
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*/
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public static float getFloat( byte[] data, int offset )
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{
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return Float.intBitsToFloat( getInt( data, offset ) );
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}
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/**
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* get an int value from the beginning of a byte array
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*
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* @param data
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* the byte array
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* @return the int (32-bit) value
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*/
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public static int getInt( byte[] data )
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{
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return getInt( data, 0 );
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}
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/**
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* get an int value from a byte array
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*
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* @param data
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* the byte array
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* @param offset
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* a starting offset into the byte array
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* @return the int (32-bit) value
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*/
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public static int getInt( byte[] data, int offset )
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{
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int i = offset;
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int b0 = data[i++] & 0xFF;
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int b1 = data[i++] & 0xFF;
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int b2 = data[i++] & 0xFF;
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int b3 = data[i++] & 0xFF;
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return ( b3 << 24 ) + ( b2 << 16 ) + ( b1 << 8 ) + ( b0 << 0 );
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}
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/**
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* get a long value from a byte array
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*
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* @param data
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* the byte array
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* @return the long (64-bit) value
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*/
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public static long getLong( byte[] data )
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{
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return getLong( data, 0 );
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}
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/**
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* get a long value from a byte array
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*
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* @param data
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* the byte array
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* @param offset
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* a starting offset into the byte array
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* @return the long (64-bit) value
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*/
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public static long getLong( byte[] data, int offset )
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{
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long result = 0xff & data[offset + 7];
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for ( int j = offset + LONG_SIZE - 1; j >= offset; j-- )
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{
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result <<= 8;
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result |= 0xff & data[j];
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}
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return result;
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}
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/**
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* get a short value from the beginning of a byte array
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*
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* @param data
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* the byte array
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* @return the short (16-bit) value
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*/
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public static short getShort( byte[] data )
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{
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return getShort( data, 0 );
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}
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/**
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* get a short value from a byte array
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*
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* @param data
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* the byte array
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* @param offset
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* a starting offset into the byte array
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* @return the short (16-bit) value
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*/
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public static short getShort( byte[] data, int offset )
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{
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int b0 = data[offset] & 0xFF;
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int b1 = data[offset + 1] & 0xFF;
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return (short) ( ( b1 << 8 ) + ( b0 << 0 ) );
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}
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/**
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* Read short array
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*
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* @param data
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* the original byte array
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* @param offset
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* Where to start copying from.
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* @param size
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* Number of bytes to copy.
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* @throws IndexOutOfBoundsException
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* - if read would cause access of data outside array bounds.
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*/
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public static short[] getShortArray( byte[] data, int offset, int size )
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{
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short[] result = new short[size / SHORT_SIZE];
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for ( int i = 0; i < result.length; i++ )
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{
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result[i] = getShort( data, offset + i * SHORT_SIZE );
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}
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return result;
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}
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/**
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* get the unsigned value of a byte.
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*
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* @param data
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* the byte array.
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* @return the unsigned value of the byte as a 16 bit short
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*/
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public static short getUByte( byte[] data )
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{
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return (short) ( data[0] & 0xFF );
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}
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/**
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* get the unsigned value of a byte.
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*
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* @param data
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* the byte array.
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* @param offset
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* a starting offset into the byte array.
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* @return the unsigned value of the byte as a 16 bit short
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*/
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public static short getUByte( byte[] data, int offset )
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{
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return (short) ( data[offset] & 0xFF );
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}
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/**
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* get an unsigned int value from a byte array
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*
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* @param data
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* the byte array
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* @return the unsigned int (32-bit) value in a long
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*/
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public static long getUInt( byte[] data )
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{
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return getUInt( data, 0 );
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}
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/**
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* get an unsigned int value from a byte array
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*
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* @param data
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* the byte array
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* @param offset
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* a starting offset into the byte array
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* @return the unsigned int (32-bit) value in a long
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*/
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public static long getUInt( byte[] data, int offset )
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{
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long retNum = getInt( data, offset );
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return retNum & 0x00FFFFFFFFl;
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}
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/**
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* get an unsigned short value from the beginning of a byte array
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*
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* @param data
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* the byte array
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* @return the unsigned short (16-bit) value in an int
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*/
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public static int getUShort( byte[] data )
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{
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return getUShort( data, 0 );
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}
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/**
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* get an unsigned short value from a byte array
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*
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* @param data
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* the byte array
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* @param offset
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* a starting offset into the byte array
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* @return the unsigned short (16-bit) value in an integer
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*/
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public static int getUShort( byte[] data, int offset )
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{
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int b0 = data[offset] & 0xFF;
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int b1 = data[offset + 1] & 0xFF;
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return ( b1 << 8 ) + ( b0 << 0 );
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}
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/**
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* executes:
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* <p/>
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* <code>
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* data[offset] = (byte)value;
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* </code>
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* </p>
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* Added for consistency with other put~() methods
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*/
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public static void putByte( byte[] data, int offset, int value )
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{
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data[offset] = (byte) value;
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}
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/**
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* put a double value into a byte array
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*
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* @param data
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* the byte array
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* @param offset
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* a starting offset into the byte array
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* @param value
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* the double (64-bit) value
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*/
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public static void putDouble( byte[] data, int offset, double value )
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{
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putLong( data, offset, Double.doubleToLongBits( value ) );
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}
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/**
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* put a double value into a byte array
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*
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* @param value
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* the double (64-bit) value
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* @param outputStream
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* output stream
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* @throws IOException
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* if an I/O error occurs
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*/
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public static void putDouble( double value, OutputStream outputStream )
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throws IOException
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{
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putLong( Double.doubleToLongBits( value ), outputStream );
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}
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/**
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* put a float value into a byte array
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*
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* @param data
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* the byte array
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* @param offset
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* a starting offset into the byte array
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* @param value
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* the float (32-bit) value
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*/
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public static void putFloat( byte[] data, int offset, float value )
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{
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putInt( data, offset, Float.floatToIntBits( value ) );
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}
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/**
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* put a float value into a byte array
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*
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* @param value
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* the float (32-bit) value
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* @param outputStream
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* output stream
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* @throws IOException
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* if an I/O error occurs
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*/
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public static void putFloat( float value, OutputStream outputStream )
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throws IOException
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{
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putInt( Float.floatToIntBits( value ), outputStream );
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}
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/**
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* put an int value into a byte array
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*
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* @param data
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* the byte array
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* @param offset
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* a starting offset into the byte array
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* @param value
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* the int (32-bit) value
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*/
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public static void putInt( byte[] data, int offset, int value )
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{
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int i = offset;
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data[i++] = (byte) ( ( value >>> 0 ) & 0xFF );
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data[i++] = (byte) ( ( value >>> 8 ) & 0xFF );
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data[i++] = (byte) ( ( value >>> 16 ) & 0xFF );
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data[i++] = (byte) ( ( value >>> 24 ) & 0xFF );
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}
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/**
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* Put int into output stream
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*
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* @param value
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* the int (32-bit) value
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* @param outputStream
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* output stream
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* @throws IOException
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* if an I/O error occurs
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*/
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public static void putInt( int value, OutputStream outputStream )
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throws IOException
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{
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outputStream.write( (byte) ( ( value >>> 0 ) & 0xFF ) );
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outputStream.write( (byte) ( ( value >>> 8 ) & 0xFF ) );
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outputStream.write( (byte) ( ( value >>> 16 ) & 0xFF ) );
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outputStream.write( (byte) ( ( value >>> 24 ) & 0xFF ) );
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}
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/**
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* put a long value into a byte array
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*
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* @param data
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* the byte array
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* @param offset
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* a starting offset into the byte array
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* @param value
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* the long (64-bit) value
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*/
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public static void putLong( byte[] data, int offset, long value )
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{
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data[offset + 0] = (byte) ( ( value >>> 0 ) & 0xFF );
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data[offset + 1] = (byte) ( ( value >>> 8 ) & 0xFF );
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data[offset + 2] = (byte) ( ( value >>> 16 ) & 0xFF );
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data[offset + 3] = (byte) ( ( value >>> 24 ) & 0xFF );
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data[offset + 4] = (byte) ( ( value >>> 32 ) & 0xFF );
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data[offset + 5] = (byte) ( ( value >>> 40 ) & 0xFF );
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data[offset + 6] = (byte) ( ( value >>> 48 ) & 0xFF );
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data[offset + 7] = (byte) ( ( value >>> 56 ) & 0xFF );
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}
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/**
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* Put long into output stream
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*
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* @param value
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* the long (64-bit) value
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* @param outputStream
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* output stream
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* @throws IOException
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* if an I/O error occurs
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*/
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public static void putLong( long value, OutputStream outputStream )
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throws IOException
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{
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outputStream.write( (byte) ( ( value >>> 0 ) & 0xFF ) );
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outputStream.write( (byte) ( ( value >>> 8 ) & 0xFF ) );
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outputStream.write( (byte) ( ( value >>> 16 ) & 0xFF ) );
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outputStream.write( (byte) ( ( value >>> 24 ) & 0xFF ) );
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outputStream.write( (byte) ( ( value >>> 32 ) & 0xFF ) );
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outputStream.write( (byte) ( ( value >>> 40 ) & 0xFF ) );
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outputStream.write( (byte) ( ( value >>> 48 ) & 0xFF ) );
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outputStream.write( (byte) ( ( value >>> 56 ) & 0xFF ) );
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}
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|
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/**
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* put a short value into a byte array
|
|
*
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* @param data
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* the byte array
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|
* @param offset
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* a starting offset into the byte array
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|
* @param value
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* the short (16-bit) value
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*/
|
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public static void putShort( byte[] data, int offset, short value )
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{
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int i = offset;
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data[i++] = (byte) ( ( value >>> 0 ) & 0xFF );
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data[i++] = (byte) ( ( value >>> 8 ) & 0xFF );
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}
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|
|
/**
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* Put signed short into output stream
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|
*
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|
* @param value
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|
* the short (16-bit) value
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|
* @param outputStream
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* output stream
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* @throws IOException
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* if an I/O error occurs
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|
*/
|
|
public static void putShort( OutputStream outputStream, short value )
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throws IOException
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{
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outputStream.write( (byte) ( ( value >>> 0 ) & 0xFF ) );
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outputStream.write( (byte) ( ( value >>> 8 ) & 0xFF ) );
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}
|
|
|
|
/**
|
|
* Stores short array in buffer
|
|
*
|
|
* @param data
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* the byte array
|
|
* @param startOffset
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|
* a starting offset into the byte array
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|
* @param value
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* the short (16-bit) values
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*/
|
|
public static void putShortArray( byte[] data, int startOffset,
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short[] value )
|
|
{
|
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int offset = startOffset;
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for ( short s : value )
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|
{
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putShort( data, offset, s );
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offset += SHORT_SIZE;
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}
|
|
}
|
|
|
|
/**
|
|
* put an unsigned byte value into a byte array
|
|
*
|
|
* @param data
|
|
* the byte array
|
|
* @param offset
|
|
* a starting offset into the byte array
|
|
* @param value
|
|
* the short (16-bit) value
|
|
*
|
|
* @exception ArrayIndexOutOfBoundsException
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|
* may be thrown
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|
*/
|
|
public static void putUByte( byte[] data, int offset, short value )
|
|
{
|
|
data[offset] = (byte) ( value & 0xFF );
|
|
}
|
|
|
|
/**
|
|
* put an unsigned int value into a byte array
|
|
*
|
|
* @param data
|
|
* the byte array
|
|
* @param offset
|
|
* a starting offset into the byte array
|
|
* @param value
|
|
* the int (32-bit) value
|
|
*
|
|
* @exception ArrayIndexOutOfBoundsException
|
|
* may be thrown
|
|
*/
|
|
public static void putUInt( byte[] data, int offset, long value )
|
|
{
|
|
int i = offset;
|
|
data[i++] = (byte) ( ( value >>> 0 ) & 0xFF );
|
|
data[i++] = (byte) ( ( value >>> 8 ) & 0xFF );
|
|
data[i++] = (byte) ( ( value >>> 16 ) & 0xFF );
|
|
data[i++] = (byte) ( ( value >>> 24 ) & 0xFF );
|
|
}
|
|
|
|
/**
|
|
* Put unsigned int into output stream
|
|
*
|
|
* @param value
|
|
* the int (32-bit) value
|
|
* @param outputStream
|
|
* output stream
|
|
* @throws IOException
|
|
* if an I/O error occurs
|
|
*/
|
|
public static void putUInt( long value, OutputStream outputStream )
|
|
throws IOException
|
|
{
|
|
outputStream.write( (byte) ( ( value >>> 0 ) & 0xFF ) );
|
|
outputStream.write( (byte) ( ( value >>> 8 ) & 0xFF ) );
|
|
outputStream.write( (byte) ( ( value >>> 16 ) & 0xFF ) );
|
|
outputStream.write( (byte) ( ( value >>> 24 ) & 0xFF ) );
|
|
}
|
|
|
|
/**
|
|
* put an unsigned short value into a byte array
|
|
*
|
|
* @param data
|
|
* the byte array
|
|
* @param offset
|
|
* a starting offset into the byte array
|
|
* @param value
|
|
* the short (16-bit) value
|
|
*
|
|
* @exception ArrayIndexOutOfBoundsException
|
|
* may be thrown
|
|
*/
|
|
public static void putUShort( byte[] data, int offset, int value )
|
|
{
|
|
int i = offset;
|
|
data[i++] = (byte) ( ( value >>> 0 ) & 0xFF );
|
|
data[i++] = (byte) ( ( value >>> 8 ) & 0xFF );
|
|
}
|
|
|
|
/**
|
|
* Put unsigned short into output stream
|
|
*
|
|
* @param value
|
|
* the unsigned short (16-bit) value
|
|
* @param outputStream
|
|
* output stream
|
|
* @throws IOException
|
|
* if an I/O error occurs
|
|
*/
|
|
public static void putUShort( int value, OutputStream outputStream )
|
|
throws IOException
|
|
{
|
|
outputStream.write( (byte) ( ( value >>> 0 ) & 0xFF ) );
|
|
outputStream.write( (byte) ( ( value >>> 8 ) & 0xFF ) );
|
|
}
|
|
|
|
/**
|
|
* get an int value from an InputStream
|
|
*
|
|
* @param stream
|
|
* the InputStream from which the int is to be read
|
|
* @return the int (32-bit) value
|
|
* @exception IOException
|
|
* will be propagated back to the caller
|
|
* @exception BufferUnderrunException
|
|
* if the stream cannot provide enough bytes
|
|
*/
|
|
public static int readInt( InputStream stream ) throws IOException,
|
|
BufferUnderrunException
|
|
{
|
|
int ch1 = stream.read();
|
|
int ch2 = stream.read();
|
|
int ch3 = stream.read();
|
|
int ch4 = stream.read();
|
|
if ( ( ch1 | ch2 | ch3 | ch4 ) < 0 )
|
|
{
|
|
throw new BufferUnderrunException();
|
|
}
|
|
return ( ch4 << 24 ) + ( ch3 << 16 ) + ( ch2 << 8 ) + ( ch1 << 0 );
|
|
}
|
|
|
|
/**
|
|
* get an unsigned int value from an InputStream
|
|
*
|
|
* @param stream
|
|
* the InputStream from which the int is to be read
|
|
* @return the unsigned int (32-bit) value
|
|
* @exception IOException
|
|
* will be propagated back to the caller
|
|
* @exception BufferUnderrunException
|
|
* if the stream cannot provide enough bytes
|
|
*/
|
|
public static long readUInt( InputStream stream ) throws IOException,
|
|
BufferUnderrunException
|
|
{
|
|
long retNum = readInt(stream);
|
|
return retNum & 0x00FFFFFFFFl;
|
|
}
|
|
|
|
/**
|
|
* get a long value from an InputStream
|
|
*
|
|
* @param stream
|
|
* the InputStream from which the long is to be read
|
|
* @return the long (64-bit) value
|
|
* @exception IOException
|
|
* will be propagated back to the caller
|
|
* @exception BufferUnderrunException
|
|
* if the stream cannot provide enough bytes
|
|
*/
|
|
public static long readLong( InputStream stream ) throws IOException,
|
|
BufferUnderrunException
|
|
{
|
|
int ch1 = stream.read();
|
|
int ch2 = stream.read();
|
|
int ch3 = stream.read();
|
|
int ch4 = stream.read();
|
|
int ch5 = stream.read();
|
|
int ch6 = stream.read();
|
|
int ch7 = stream.read();
|
|
int ch8 = stream.read();
|
|
if ( ( ch1 | ch2 | ch3 | ch4 | ch5 | ch6 | ch7 | ch8 ) < 0 )
|
|
{
|
|
throw new BufferUnderrunException();
|
|
}
|
|
|
|
return ( (long) ch8 << 56 ) + ( (long) ch7 << 48 )
|
|
+ ( (long) ch6 << 40 ) + ( (long) ch5 << 32 )
|
|
+ ( (long) ch4 << 24 ) + // cast to long to preserve bit 31
|
|
// (sign bit for ints)
|
|
( ch3 << 16 ) + ( ch2 << 8 ) + ( ch1 << 0 );
|
|
}
|
|
|
|
/**
|
|
* get a short value from an InputStream
|
|
*
|
|
* @param stream
|
|
* the InputStream from which the short is to be read
|
|
* @return the short (16-bit) value
|
|
* @exception IOException
|
|
* will be propagated back to the caller
|
|
* @exception BufferUnderrunException
|
|
* if the stream cannot provide enough bytes
|
|
*/
|
|
public static short readShort( InputStream stream ) throws IOException,
|
|
BufferUnderrunException
|
|
{
|
|
return (short) readUShort( stream );
|
|
}
|
|
|
|
public static int readUShort( InputStream stream ) throws IOException,
|
|
BufferUnderrunException
|
|
{
|
|
int ch1 = stream.read();
|
|
int ch2 = stream.read();
|
|
if ( ( ch1 | ch2 ) < 0 )
|
|
{
|
|
throw new BufferUnderrunException();
|
|
}
|
|
return ( ch2 << 8 ) + ( ch1 << 0 );
|
|
}
|
|
|
|
/**
|
|
* Convert an 'unsigned' byte to an integer. ie, don't carry across the
|
|
* sign.
|
|
*
|
|
* @param b
|
|
* Description of the Parameter
|
|
* @return Description of the Return Value
|
|
*/
|
|
public static int ubyteToInt( byte b )
|
|
{
|
|
return b & 0xFF;
|
|
}
|
|
|
|
private LittleEndian()
|
|
{
|
|
// no instances of this class
|
|
}
|
|
}
|