# PDPattern.java

    /*
     * 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.pdfbox.pdmodel.graphics.color;

    import java.awt.image.BufferedImage;
    import java.awt.image.WritableRaster;
    import java.io.IOException;

    import org.apache.pdfbox.cos.COSArray;
    import org.apache.pdfbox.cos.COSName;
    import org.apache.pdfbox.pdmodel.PDResources;
    import org.apache.pdfbox.pdmodel.graphics.pattern.PDAbstractPattern;

    /**
     * A Pattern color space is either a Tiling pattern or a Shading pattern.
     * @author John Hewson
     * @author Ben Litchfield
     */
    public final class PDPattern extends PDSpecialColorSpace
    {
        /** A pattern which leaves no marks on the page. */
        private static final PDColor EMPTY_PATTERN = new PDColor(new float[] { }, null);

        private final PDResources resources;
        private PDColorSpace underlyingColorSpace;

        /**
         * Creates a new pattern color space.
         *
         * @param resources The current resources.
         */
        public PDPattern(PDResources resources)
        {
            this.resources = resources;
            array = new COSArray();
            array.add(COSName.PATTERN);
        }

        /**
         * Creates a new uncolored tiling pattern color space.
         *
         * @param resources The current resources.
         * @param colorSpace The underlying color space.
         */
        public PDPattern(PDResources resources, PDColorSpace colorSpace)
        {
            this.resources = resources;
            this.underlyingColorSpace = colorSpace;
            array = new COSArray();
            array.add(COSName.PATTERN);
            array.add(colorSpace);
        }

        @Override
        public String getName()
        {
            return COSName.PATTERN.getName();
        }

        @Override
        public int getNumberOfComponents()
        {
            throw new UnsupportedOperationException();
        }

        @Override
        public float[] getDefaultDecode(int bitsPerComponent)
        {
            throw new UnsupportedOperationException();
        }

        @Override
        public PDColor getInitialColor()
        {
            return EMPTY_PATTERN;
        }

        @Override
        public float[] toRGB(float[] value)
        {
            throw new UnsupportedOperationException();
        }

        @Override
        public BufferedImage toRGBImage(WritableRaster raster) throws IOException
        {
            throw new UnsupportedOperationException();
        }

        @Override
        public BufferedImage toRawImage(WritableRaster raster) throws IOException
        {
            throw new UnsupportedOperationException();
        }

        /**
         * Returns the pattern for the given color.
         *
         * @param color color containing a pattern name
         * @return pattern for the given color
         * @throws java.io.IOException if the pattern name was not found.
         */
        public PDAbstractPattern getPattern(PDColor color) throws IOException
        {
            PDAbstractPattern pattern = resources.getPattern(color.getPatternName());
            if (pattern == null)
            {
                throw new IOException("pattern " + color.getPatternName() + " was not found");
            }
            else
            {
                return pattern;
            }
        }

        /**
         * Returns the underlying color space, if this is an uncolored tiling pattern, otherwise null.
         */
        public PDColorSpace getUnderlyingColorSpace()
        {
            return underlyingColorSpace;
        }

        @Override
        public String toString()
        {
            return "Pattern";
        }
    }