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   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
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       http://www.apache.org/licenses/LICENSE-2.0

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package org.apache.poi.hpsf;

import java.io.IOException;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.math.BigInteger;
import java.util.Date;
import java.util.LinkedList;
import java.util.List;

import org.apache.poi.util.IOUtils;
import org.apache.poi.util.LittleEndian;
import org.apache.poi.util.LittleEndianByteArrayInputStream;
import org.apache.poi.util.LittleEndianConsts;
import org.apache.poi.util.POILogFactory;
import org.apache.poi.util.POILogger;

/**
 * Supports reading and writing of variant data.

* * FIXME (3): Reading and writing should be made more * uniform than it is now. The following items should be resolved: * *

    * *
  • Reading requires a length parameter that is 4 byte greater than the * actual data, because the variant type field is included. * *
  • Reading reads from a byte array while writing writes to an byte array * output stream. * *
*/ public class VariantSupport extends Variant { /** * HPSF is able to read these {@link Variant} types. */ public static final int[] SUPPORTED_TYPES = { Variant.VT_EMPTY, Variant.VT_I2, Variant.VT_I4, Variant.VT_I8, Variant.VT_R8, Variant.VT_FILETIME, Variant.VT_LPSTR, Variant.VT_LPWSTR, Variant.VT_CF, Variant.VT_BOOL }; private static final POILogger logger = POILogFactory.getLogger(VariantSupport.class); //arbitrarily selected; may need to increase private static final int MAX_RECORD_LENGTH = 100_000; private static boolean logUnsupportedTypes; /** * Keeps a list of the variant types an "unsupported" message has already * been issued for. */ private static List unsupportedMessage; private static final byte[] paddingBytes = new byte[3]; /** * Specifies whether warnings about unsupported variant types are to be * written to {@code System.err} or not. * * @param logUnsupportedTypes If {@code true} warnings will be written, * if {@code false} they won't. */ public static void setLogUnsupportedTypes(final boolean logUnsupportedTypes) { VariantSupport.logUnsupportedTypes = logUnsupportedTypes; } /** * Checks whether logging of unsupported variant types warning is turned * on or off. * * @return {@code true} if logging is turned on, else * {@code false}. */ public static boolean isLogUnsupportedTypes() { return logUnsupportedTypes; } /** * Writes a warning to {@code System.err} that a variant type is * unsupported by HPSF. Such a warning is written only once for each variant * type. Log messages can be turned on or off by * * @param ex The exception to log */ protected static void writeUnsupportedTypeMessage (final UnsupportedVariantTypeException ex) { if (isLogUnsupportedTypes()) { if (unsupportedMessage == null) { unsupportedMessage = new LinkedList<>(); } Long vt = Long.valueOf(ex.getVariantType()); if (!unsupportedMessage.contains(vt)) { logger.log( POILogger.ERROR, ex.getMessage()); unsupportedMessage.add(vt); } } } /** * Checks whether HPSF supports the specified variant type. Unsupported * types should be implemented included in the {@link #SUPPORTED_TYPES} * array. * * @see Variant * @param variantType the variant type to check * @return {@code true} if HPFS supports this type, else * {@code false} */ public boolean isSupportedType(final int variantType) { for (int st : SUPPORTED_TYPES) { if (variantType == st) { return true; } } return false; } /** * Reads a variant type from a byte array. * * @param src The byte array * @param offset The offset in the byte array where the variant starts * @param length The length of the variant including the variant type field * @param type The variant type to read * @param codepage The codepage to use for non-wide strings * @return A Java object that corresponds best to the variant field. For * example, a VT_I4 is returned as a {@link Long}, a VT_LPSTR as a * {@link String}. * @exception ReadingNotSupportedException if a property is to be written * who's variant type HPSF does not yet support * @exception UnsupportedEncodingException if the specified codepage is not * supported. * @see Variant */ public static Object read( final byte[] src, final int offset, final int length, final long type, final int codepage ) throws ReadingNotSupportedException, UnsupportedEncodingException { LittleEndianByteArrayInputStream lei = new LittleEndianByteArrayInputStream(src, offset); return read( lei, length, type, codepage ); } public static Object read( LittleEndianByteArrayInputStream lei, final int length, final long type, final int codepage ) throws ReadingNotSupportedException, UnsupportedEncodingException { final int offset = lei.getReadIndex(); TypedPropertyValue typedPropertyValue = new TypedPropertyValue( (int) type, null ); try { typedPropertyValue.readValue(lei); } catch ( UnsupportedOperationException exc ) { try { final byte[] v = IOUtils.toByteArray(lei, length, MAX_RECORD_LENGTH); throw new ReadingNotSupportedException( type, v ); } catch (IOException e) { throw new RuntimeException(e); } } switch ( (int) type ) { /* * we have more property types that can be converted into Java * objects, but current API need to be preserved, and it returns * other types as byte arrays. In future major versions it shall be * changed -- sergey */ case Variant.VT_EMPTY: case Variant.VT_I1: case Variant.VT_UI1: case Variant.VT_UI2: case Variant.VT_I4: case Variant.VT_UI4: case Variant.VT_I8: case Variant.VT_UI8: case Variant.VT_R4: case Variant.VT_R8: return typedPropertyValue.getValue(); /* * also for backward-compatibility with prev. versions of POI * --sergey */ case Variant.VT_I2: return ( (Short) typedPropertyValue.getValue() ).intValue(); case Variant.VT_FILETIME: Filetime filetime = (Filetime) typedPropertyValue.getValue(); return filetime.getJavaValue(); case Variant.VT_LPSTR: CodePageString cpString = (CodePageString) typedPropertyValue.getValue(); return cpString.getJavaValue( codepage ); case Variant.VT_LPWSTR: UnicodeString uniString = (UnicodeString) typedPropertyValue.getValue(); return uniString.toJavaString(); // if(l1 < 0) { /* * YK: reading the ClipboardData packet (VT_CF) is not quite * correct. The size of the data is determined by the first four * bytes of the packet while the current implementation calculates * it in the Section constructor. Test files in Bugzilla 42726 and * 45583 clearly show that this approach does not always work. The * workaround below attempts to gracefully handle such cases instead * of throwing exceptions. * * August 20, 2009 */ // l1 = LittleEndian.getInt(src, o1); o1 += LittleEndian.INT_SIZE; // } // final byte[] v = new byte[l1]; // System.arraycopy(src, o1, v, 0, v.length); // value = v; // break; case Variant.VT_CF: ClipboardData clipboardData = (ClipboardData) typedPropertyValue.getValue(); return clipboardData.toByteArray(); case Variant.VT_BOOL: VariantBool bool = (VariantBool) typedPropertyValue.getValue(); return bool.getValue(); /* * it is not very good, but what can do without breaking current * API? --sergey */ default: final int unpadded = lei.getReadIndex()-offset; lei.setReadIndex(offset); final byte[] v = IOUtils.safelyAllocate(unpadded, MAX_RECORD_LENGTH); lei.readFully( v, 0, unpadded ); throw new ReadingNotSupportedException( type, v ); } } /** * Writes a variant value to an output stream. This method ensures that * always a multiple of 4 bytes is written.

* * @param out The stream to write the value to. * @param type The variant's type. * @param value The variant's value. * @param codepage The codepage to use to write non-wide strings * @return The number of entities that have been written. In many cases an * "entity" is a byte but this is not always the case. * @exception IOException if an I/O exceptions occurs * @exception WritingNotSupportedException if a property is to be written * who's variant type HPSF does not yet support */ public static int write(final OutputStream out, final long type, final Object value, final int codepage) throws IOException, WritingNotSupportedException { int length = -1; switch ((int) type) { case Variant.VT_BOOL: { if (value instanceof Boolean) { int bb = ((Boolean)value) ? 0xff : 0x00; out.write(bb); out.write(bb); length = 2; } break; } case Variant.VT_LPSTR: if (value instanceof String) { CodePageString codePageString = new CodePageString(); codePageString.setJavaValue( (String)value, codepage ); length = codePageString.write( out ); } break; case Variant.VT_LPWSTR: if (value instanceof String) { UnicodeString uniString = new UnicodeString(); uniString.setJavaValue((String)value); length = uniString.write(out); } break; case Variant.VT_CF: if (value instanceof byte[]) { final byte[] cf = (byte[]) value; out.write(cf); length = cf.length; } break; case Variant.VT_EMPTY: LittleEndian.putUInt(Variant.VT_EMPTY, out); length = LittleEndianConsts.INT_SIZE; break; case Variant.VT_I2: if (value instanceof Number) { LittleEndian.putShort( out, ((Number)value).shortValue() ); length = LittleEndianConsts.SHORT_SIZE; } break; case Variant.VT_UI2: if (value instanceof Number) { LittleEndian.putUShort( ((Number)value).intValue(), out ); length = LittleEndianConsts.SHORT_SIZE; } break; case Variant.VT_I4: if (value instanceof Number) { LittleEndian.putInt( ((Number)value).intValue(), out); length = LittleEndianConsts.INT_SIZE; } break; case Variant.VT_UI4: if (value instanceof Number) { LittleEndian.putUInt( ((Number)value).longValue(), out); length = LittleEndianConsts.INT_SIZE; } break; case Variant.VT_I8: if (value instanceof Number) { LittleEndian.putLong( ((Number)value).longValue(), out); length = LittleEndianConsts.LONG_SIZE; } break; case Variant.VT_UI8: { if (value instanceof Number) { BigInteger bi = (value instanceof BigInteger) ? (BigInteger)value : BigInteger.valueOf(((Number)value).longValue()); if (bi.bitLength() > 64) { throw new WritingNotSupportedException(type, value); } byte[] biBytesBE = bi.toByteArray(), biBytesLE = new byte[LittleEndianConsts.LONG_SIZE]; int i=biBytesBE.length; for (byte b : biBytesBE) { if (i<=LittleEndianConsts.LONG_SIZE) { biBytesLE[i-1] = b; } i--; } out.write(biBytesLE); length = LittleEndianConsts.LONG_SIZE; } break; } case Variant.VT_R4: { if (value instanceof Number) { int floatBits = Float.floatToIntBits(((Number)value).floatValue()); LittleEndian.putInt(floatBits, out); length = LittleEndianConsts.INT_SIZE; } break; } case Variant.VT_R8: if (value instanceof Number) { LittleEndian.putDouble( ((Number)value).doubleValue(), out); length = LittleEndianConsts.DOUBLE_SIZE; } break; case Variant.VT_FILETIME: Filetime filetimeValue = (value instanceof Date) ? new Filetime((Date)value) : new Filetime(); length = filetimeValue.write( out ); break; default: break; } /* The variant type is not supported yet. However, if the value * is a byte array we can write it nevertheless. */ if (length == -1) { if (value instanceof byte[]) { final byte[] b = (byte[]) value; out.write(b); length = b.length; writeUnsupportedTypeMessage(new WritingNotSupportedException(type, value)); } else { throw new WritingNotSupportedException(type, value); } } /* pad values to 4-bytes */ int padding = (4-(length & 0x3)) & 0x3; out.write(paddingBytes, 0, padding); return length + padding; } }





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