    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017package org.apache.commons.imaging.formats.tiff.taginfos;
    018
    019import java.nio.ByteOrder;
    020import java.nio.charset.StandardCharsets;
    021
    022import org.apache.commons.imaging.ImagingException;
    023import org.apache.commons.imaging.common.Allocator;
    024import org.apache.commons.imaging.formats.tiff.constants.TiffDirectoryType;
    025import org.apache.commons.imaging.formats.tiff.fieldtypes.AbstractFieldType;
    026
    027public class TagInfoAscii extends TagInfo {
    028    public TagInfoAscii(final String name, final int tag, final int length, final TiffDirectoryType directoryType) {
    029        super(name, tag, AbstractFieldType.ASCII, length, directoryType);
    030    }
    031
    032    public byte[] encodeValue(final ByteOrder byteOrder, final String... values) throws ImagingException {
    033        return AbstractFieldType.ASCII.writeData(values, byteOrder);
    034    }
    035
    036    public String[] getValue(final ByteOrder byteOrder, final byte[] bytes) {
    037        int nullCount = 0;
    038        for (int i = 0; i < bytes.length - 1; i++) {
    039            if (bytes[i] == 0) {
    040                nullCount++;
    041            }
    042        }
    043        final String[] strings = Allocator.array(nullCount + 1, String[]::new, 24);
    044        int stringsAdded = 0;
    045        strings[0] = ""; // if we have a 0 length string
    046        int nextStringPos = 0;
    047        // According to the Exiftool FAQ, [BROKEN URL] http://www.metadataworkinggroup.org
    048        // specifies that the TIFF ASCII fields are actually UTF-8.
    049        // Exiftool however allows you to configure the charset used.
    050        for (int i = 0; i < bytes.length; i++) {
    051            if (bytes[i] == 0) {
    052                final String string = new String(bytes, nextStringPos, i - nextStringPos, StandardCharsets.UTF_8);
    053                strings[stringsAdded++] = string;
    054                nextStringPos = i + 1;
    055            }
    056        }
    057        if (nextStringPos < bytes.length) {
    058            // Buggy file, string wasn't null terminated
    059            final String string = new String(bytes, nextStringPos, bytes.length - nextStringPos, StandardCharsets.UTF_8);
    060            strings[stringsAdded++] = string;
    061        }
    062        return strings;
    063    }
    064}