com.formkiq.vision.pdf.ImagePDFStreamEngine Maven / Gradle / Ivy

Go to download
/*
 * Copyright (C) 2018 FormKiQ Inc.
 *
 * 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 com.formkiq.vision.pdf;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import javax.imageio.ImageIO;

import org.apache.commons.lang3.Range;
import org.apache.pdfbox.contentstream.PDFStreamEngine;
import org.apache.pdfbox.contentstream.operator.Operator;
import org.apache.pdfbox.cos.COSBase;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.pdmodel.common.PDRectangle;
import org.apache.pdfbox.pdmodel.graphics.PDXObject;
import org.apache.pdfbox.pdmodel.graphics.form.PDFormXObject;
import org.apache.pdfbox.pdmodel.graphics.image.PDImageXObject;

/**
 * {@link PDFStreamEngine} for Images.
 *
 */
public class ImagePDFStreamEngine extends PDFStreamEngine {

	/** {@link PdfDocumentObjects}. */
	private PdfDocumentObjects tokenResult;

    /** {@link List} {@link PdfImage}. */
    private List images;

    /**
     * constructor.
     * @param result {@link PdfDocumentObjects}
     */
    public ImagePDFStreamEngine(final PdfDocumentObjects result) {
    	this.images = new ArrayList<>();
		this.tokenResult = result;
	}

	/**
     * This is used to handle an operation.
     *
     * @param operator The operation to perform.
     * @param operands The list of arguments.
     *
     * @throws IOException If there is an error processing the operation.
     */
    @Override
    protected void processOperator(final Operator operator,
            final List operands) throws IOException {

        String operation = operator.getName();

        if ("Do".equals(operation)) {

            COSName objectName = (COSName) operands.get(0);
            PDXObject xobject = getResources().getXObject(objectName);

            if (xobject instanceof PDImageXObject) {

                PDImageXObject image = (PDImageXObject) xobject;
                int imageWidth = image.getWidth();
                int imageHeight = image.getHeight();

                PDRectangle imageRect = this.tokenResult
                        .getObjectRectangle(objectName.getName());

                PdfImage pdfImage = new PdfImage();
                pdfImage.setImageName(objectName.getName());
                pdfImage.setImage(toBytes(image, pdfImage.getImagetype()));
                pdfImage.setWidth(imageWidth);
                pdfImage.setHeight(imageHeight);

                pdfImage.setX(Range.between(
                        Float.valueOf(imageRect.getUpperRightX()),
                        Float.valueOf(
                                imageRect.getUpperRightX() + imageWidth)));
                pdfImage.setY(Range.between(
                        Float.valueOf(imageRect.getUpperRightY()),
                        Float.valueOf(
                                imageRect.getUpperRightY() + imageHeight)));

                this.images.add(pdfImage);

            } else if (xobject instanceof PDFormXObject) {
                PDFormXObject form = (PDFormXObject) xobject;
                showForm(form);
            }
        } else {
            super.processOperator(operator, operands);
        }
    }

    /**
     * Convert {@link PDImageXObject} to byte[].
     * @param image {@link PDImageXObject}
     * @param imageType {@link String}
     * @return byte[]
     */
    private byte[] toBytes(final PDImageXObject image, final String imageType) {
    	
      ByteArrayOutputStream bytes = new ByteArrayOutputStream();

      try {
          ImageIO.write(image.getImage(), imageType, bytes);
      } catch (IOException e) {
          throw new RuntimeException(e);
      }

      return bytes.toByteArray();
    }
    
    /**
     * @return {@link List} {@link PdfImage}
     */
    public List getImages() {
        return this.images;
    }
}