org.pdfgal.pdfgalweb.validators.MergeValidator.java Source code

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Here is the source code for org.pdfgal.pdfgalweb.validators.MergeValidator.java

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/*
 * PDFGalWeb
 * Copyright (c) 2014, Alejandro Pernas Pan, All rights reserved.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3.0 of the License, or (at your option) any later version.
    
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library.
 */

package org.pdfgal.pdfgalweb.validators;

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

import org.apache.commons.collections.CollectionUtils;
import org.pdfgal.pdfgal.validator.PDFGalValidator;
import org.pdfgal.pdfgalweb.forms.MergeForm;
import org.pdfgal.pdfgalweb.model.enumerated.PDFEncryptionType;
import org.pdfgal.pdfgalweb.utils.FileUtils;
import org.pdfgal.pdfgalweb.utils.ZipUtils;
import org.pdfgal.pdfgalweb.validators.utils.ValidatorUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.validation.Errors;
import org.springframework.validation.ValidationUtils;
import org.springframework.validation.Validator;
import org.springframework.web.multipart.MultipartFile;

@Component
public class MergeValidator implements Validator {

    @Autowired
    private FileUtils fileUtils;

    @Autowired
    private PDFGalValidator pdfGalValidator;

    @Autowired
    private ValidatorUtils validatorUtils;

    @Autowired
    private ZipUtils zipUtils;

    @Override
    public boolean supports(final Class<?> clazz) {
        return MergeForm.class.equals(clazz);
    }

    @Override
    public void validate(final Object target, final Errors errors) {

        final MergeForm mergeForm = (MergeForm) target;

        // File name validator
        ValidationUtils.rejectIfEmptyOrWhitespace(errors, "fileName", "merge.validator.file.name.required");
        if (!this.validatorUtils.validateFileName(mergeForm.getFileName())) {
            errors.rejectValue("fileName", "merge.validator.file.name.invalid");
        }

        // Uploaded files validator
        final List<MultipartFile> files = mergeForm.getFiles();

        if (this.isEmpty(files)) {
            // There are no files uploaded
            errors.rejectValue("files", "merge.validator.files.required");

        } else if (files.size() == 1) {
            // There is only one file uploaded
            this.validateZipFile(files.get(0), errors);

        } else {
            // There are more than one file uploaded
            final PDFEncryptionType validation = this.validatePDF(files);
            if (PDFEncryptionType.NON_PDF.equals(validation)) {
                errors.rejectValue("files", "merge.validator.files.incorrect.pdf");
            } else if (PDFEncryptionType.ENCRYPTED.equals(validation)) {
                errors.rejectValue("files", "merge.validator.files.incorrect.encrypted");
            }
        }
    }

    /**
     * Makes the validation for a single ZIP file
     * 
     * @param file
     * @param errors
     */
    private void validateZipFile(final MultipartFile file, final Errors errors) {

        try {
            InputStream fileInputStream = file.getInputStream();

            if (!this.zipUtils.isZip(fileInputStream)) {
                // In case the file is not ZIP we show error, file must be a
                // ZIP
                errors.rejectValue("files", "merge.validator.files.incorrect.zip");

            } else {
                // If file is ZIP, every file inside must be PDF
                List<String> urisList = new ArrayList<String>();

                // InputStream is closed previously so we must get it again
                fileInputStream = file.getInputStream();
                urisList = this.zipUtils.saveFilesFromZip(fileInputStream);

                for (final String uri : urisList) {
                    if (!this.pdfGalValidator.isPDF(uri)) {
                        errors.rejectValue("files", "merge.validator.files.incorrect.zip.pdf");
                        break;
                    }
                    if (this.pdfGalValidator.isEncrypted(uri)) {
                        errors.rejectValue("files", "merge.validator.files.incorrect.zip.encrypted");
                        break;
                    }
                }

                this.fileUtils.delete(urisList);
            }

            fileInputStream.close();

        } catch (final IOException e) {
            errors.rejectValue("files", "merge.validator.files.incorrect.zip");
        }
    }

    /**
     * This method returns true when every file on the list is empty, or the
     * list is empty.
     * 
     * @param files
     * @return
     */
    private boolean isEmpty(final List<MultipartFile> files) {

        boolean result = true;

        if (CollectionUtils.isNotEmpty(files)) {
            for (final MultipartFile file : files) {
                if (file.getSize() != 0) {
                    result = false;
                    break;
                }
            }
        }

        return result;
    }

    /**
     * This method validates a files list, it returns a
     * {@link PDFEncryptionType} indicating if one the files is not a PDF, if it
     * is an encrypted PDF or if each one of the are not encrypted PDFs.
     * 
     * @param files
     * @return
     */
    private PDFEncryptionType validatePDF(final List<MultipartFile> files) {

        PDFEncryptionType result = PDFEncryptionType.NON_ENCRYPTED;

        for (final MultipartFile file : files) {
            if (file.getSize() > 0) {
                final PDFEncryptionType validation = this.validatorUtils.validatePDF(file);
                if (!PDFEncryptionType.NON_ENCRYPTED.equals(validation)) {
                    result = validation;
                    break;
                }
            }
        }

        return result;
    }
}