# PDAnnotationCaret.java

    /*
     * Copyright 2018 The Apache Software Foundation.
     *
     * Licensed 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.interactive.annotation;

    import org.apache.pdfbox.cos.COSArray;
    import org.apache.pdfbox.cos.COSDictionary;
    import org.apache.pdfbox.cos.COSFloat;
    import org.apache.pdfbox.cos.COSName;
    import org.apache.pdfbox.pdmodel.PDDocument;
    import org.apache.pdfbox.pdmodel.interactive.annotation.handlers.PDAppearanceHandler;
    import org.apache.pdfbox.pdmodel.interactive.annotation.handlers.PDCaretAppearanceHandler;

    /**
     *
     * @author Paul King
     */
    public class PDAnnotationCaret extends PDAnnotationMarkup
    {
        /**
         * The type of annotation.
         */
        public static final String SUB_TYPE = "Caret";

        private PDAppearanceHandler customAppearanceHandler;

        public PDAnnotationCaret()
        {
            getCOSObject().setName(COSName.SUBTYPE, SUB_TYPE);
        }

        /**
         * Creates a Caret annotation from a COSDictionary, expected to be a correct object definition.
         *
         * @param field the PDF object to represent as a field.
         */
        public PDAnnotationCaret(COSDictionary field)
        {
            super(field);
        }

        /**
         * This will set the difference between the annotations "outer" rectangle defined by
         * /Rect and boundaries of the underlying.
         *
         * <p>This will set an equal difference for all sides</p>
         *
         * @param difference from the annotations /Rect entry
         */
        public void setRectDifferences(float difference) {
            setRectDifferences(difference, difference, difference, difference);
        }

        /**
         * This will set the difference between the annotations "outer" rectangle defined by
         * /Rect and the border.
         *
         * @param differenceLeft left difference from the annotations /Rect entry
         * @param differenceTop top difference from the annotations /Rect entry
         * @param differenceRight right difference from  the annotations /Rect entry
         * @param differenceBottom bottom difference from the annotations /Rect entry
         *
         */
        public void setRectDifferences(float differenceLeft, float differenceTop, float differenceRight, float differenceBottom)
        {
            COSArray margins = new COSArray();
            margins.add(new COSFloat(differenceLeft));
            margins.add(new COSFloat(differenceTop));
            margins.add(new COSFloat(differenceRight));
            margins.add(new COSFloat(differenceBottom));
            getCOSObject().setItem(COSName.RD, margins);
        }

        /**
         * This will get the margin between the annotations "outer" rectangle defined by
         * /Rect and the boundaries of the underlying caret.
         *
         * @return the differences. If the entry hasn't been set am empty array is returned.
         */
        public float[] getRectDifferences()
        {
            COSArray margin = getCOSObject().getCOSArray(COSName.RD);
            return margin != null ? margin.toFloatArray() : new float[] {};
        }

        /**
         * Set a custom appearance handler for generating the annotations appearance streams.
         *
         * @param appearanceHandler
         */
        public void setCustomAppearanceHandler(PDAppearanceHandler appearanceHandler)
        {
            customAppearanceHandler = appearanceHandler;
        }

        @Override
        public void constructAppearances()
        {
            this.constructAppearances(null);
        }

        @Override
        public void constructAppearances(PDDocument document)
        {
            if (customAppearanceHandler == null)
            {
                PDCaretAppearanceHandler appearanceHandler = new PDCaretAppearanceHandler(this, document);
                appearanceHandler.generateAppearanceStreams();
            }
            else
            {
                customAppearanceHandler.generateAppearanceStreams();
            }
        }
    }