123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108 |
- /* ====================================================================
- 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.xssf.binary;
-
-
- import java.nio.charset.Charset;
-
- import org.apache.poi.POIXMLException;
- import org.apache.poi.util.Internal;
- import org.apache.poi.util.LittleEndian;
-
- @Internal
- public class XSSFBUtils {
-
- /**
- * Reads an XLNullableWideString.
- * @param data data from which to read
- * @param offset in data from which to start
- * @param sb buffer to which to write. You must setLength(0) before calling!
- * @return number of bytes read
- * @throws XSSFBParseException if there was an exception during reading
- */
- static int readXLNullableWideString(byte[] data, int offset, StringBuilder sb) throws XSSFBParseException {
- long numChars = LittleEndian.getUInt(data, offset);
- if (numChars < 0) {
- throw new XSSFBParseException("too few chars to read");
- } else if (numChars == 0xFFFFFFFFL) { //this means null value (2.5.166), do not read any bytes!!!
- return 0;
- } else if (numChars > 0xFFFFFFFFL) {
- throw new XSSFBParseException("too many chars to read");
- }
-
- int numBytes = 2*(int)numChars;
- offset += 4;
- if (offset+numBytes > data.length) {
- throw new XSSFBParseException("trying to read beyond data length:" +
- "offset="+offset+", numBytes="+numBytes+", data.length="+data.length);
- }
- sb.append(new String(data, offset, numBytes, Charset.forName("UTF-16LE")));
- numBytes+=4;
- return numBytes;
- }
-
-
- /**
- * Reads an XLNullableWideString.
- * @param data data from which to read
- * @param offset in data from which to start
- * @param sb buffer to which to write. You must setLength(0) before calling!
- * @return number of bytes read
- * @throws XSSFBParseException if there was an exception while trying to read the string
- */
- public static int readXLWideString(byte[] data, int offset, StringBuilder sb) throws XSSFBParseException {
- long numChars = LittleEndian.getUInt(data, offset);
- if (numChars < 0) {
- throw new XSSFBParseException("too few chars to read");
- } else if (numChars > 0xFFFFFFFFL) {
- throw new XSSFBParseException("too many chars to read");
- }
- int numBytes = 2*(int)numChars;
- offset += 4;
- if (offset+numBytes > data.length) {
- throw new XSSFBParseException("trying to read beyond data length");
- }
- sb.append(new String(data, offset, numBytes, Charset.forName("UTF-16LE")));
- numBytes+=4;
- return numBytes;
- }
-
- static int castToInt(long val) {
- if (val < Integer.MAX_VALUE && val > Integer.MIN_VALUE) {
- return (int)val;
- }
- throw new POIXMLException("val ("+val+") can't be cast to int");
- }
-
- static short castToShort(int val) {
- if (val < Short.MAX_VALUE && val > Short.MIN_VALUE) {
- return (short)val;
- }
- throw new POIXMLException("val ("+val+") can't be cast to short");
-
- }
-
- //TODO: move to LittleEndian?
- static int get24BitInt( byte[] data, int offset) {
- int i = offset;
- int b0 = data[i++] & 0xFF;
- int b1 = data[i++] & 0xFF;
- int b2 = data[i] & 0xFF;
- return ( b2 << 16 ) + ( b1 << 8 ) + b0;
- }
- }
|