Java tutorial
/******************************************************************************* * Copyright 2010 Atos Worldline SAS * * Licensed by Atos Worldline SAS under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * Atos Worldline SAS 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 net.padaf.preflight.graphics; import static net.padaf.preflight.ValidationConstants.ERROR_TRANSPARENCY_EXT_GS_BLEND_MODE; import static net.padaf.preflight.ValidationConstants.ERROR_TRANSPARENCY_EXT_GS_CA; import static net.padaf.preflight.ValidationConstants.ERROR_TRANSPARENCY_EXT_GS_SOFT_MASK; import static net.padaf.preflight.ValidationConstants.TRANPARENCY_DICTIONARY_KEY_EXTGSTATE; import static net.padaf.preflight.ValidationConstants.TRANPARENCY_DICTIONARY_KEY_EXTGSTATE_ENTRY_REGEX; import static net.padaf.preflight.ValidationConstants.TRANSPARENCY_DICTIONARY_KEY_BLEND_MODE; import static net.padaf.preflight.ValidationConstants.TRANSPARENCY_DICTIONARY_KEY_LOWER_CA; import static net.padaf.preflight.ValidationConstants.TRANSPARENCY_DICTIONARY_KEY_SOFT_MASK; import static net.padaf.preflight.ValidationConstants.TRANSPARENCY_DICTIONARY_KEY_UPPER_CA; import static net.padaf.preflight.ValidationConstants.TRANSPARENCY_DICTIONARY_VALUE_BM_COMPATIBLE; import static net.padaf.preflight.ValidationConstants.TRANSPARENCY_DICTIONARY_VALUE_BM_NORMAL; import static net.padaf.preflight.ValidationConstants.TRANSPARENCY_DICTIONARY_VALUE_SOFT_MASK_NONE; import java.util.ArrayList; import java.util.List; import net.padaf.preflight.ValidationConstants; import net.padaf.preflight.ValidationException; import net.padaf.preflight.ValidationResult.ValidationError; import net.padaf.preflight.utils.COSUtils; import net.padaf.preflight.utils.RenderingIntents; import org.apache.pdfbox.cos.COSBase; import org.apache.pdfbox.cos.COSDictionary; import org.apache.pdfbox.cos.COSDocument; import org.apache.pdfbox.cos.COSName; /** * This class wraps a list of COSDictionary which represent an extended graphics * state dictionary. */ public class ExtGStateContainer { /** * The COSDocument which contains the extended graphic states. */ private COSDocument cDoc = null; /** * A list of Extended Graphic States. */ private List<COSDictionary> listOfExtGState = new ArrayList<COSDictionary>(0); /** * Create an instance of ExtGStateContainer using a Resource dictionary and a * COSDocument. This constructor initializes the listOfExtGState attribute * using the given Resource dictionary and the COSDocument. * * @param resources * a resource COSDictionary * @param cDoc * the COSDocument which contains the Resource dictionary * @throws ValidationException * thrown if a the Extended Graphic State isn't valid */ public ExtGStateContainer(COSDictionary resources, COSDocument cDoc) throws ValidationException { this.cDoc = cDoc; COSBase egsEntry = resources.getItem(COSName.getPDFName(TRANPARENCY_DICTIONARY_KEY_EXTGSTATE)); COSDictionary extGStates = COSUtils.getAsDictionary(egsEntry, cDoc); if (extGStates != null) { for (Object object : extGStates.keySet()) { COSName key = (COSName) object; if (key.getName().matches(TRANPARENCY_DICTIONARY_KEY_EXTGSTATE_ENTRY_REGEX)) { COSBase gsBase = extGStates.getItem(key); COSDictionary gsDict = COSUtils.getAsDictionary(gsBase, cDoc); if (gsDict == null) { throw new ValidationException("The Extended Graphics State dictionary is invalid"); } this.listOfExtGState.add(gsDict); } } } //else if there are no ExtGState, the list will be empty. } /** * Validate all ExtGState dictionaries of this container * * @param error * the list of error to update if the validation fails. * @return true if all Graphic States are valid, false otherwise. */ public boolean validateTransparencyRules(List<ValidationError> error) { boolean res = true; for (COSDictionary egs : listOfExtGState) { res = res && checkSoftMask(egs, error); res = res && checkCA(egs, error); res = res && checkBlendMode(egs, error); res = res && checkTRKey(egs, error); res = res && checkTR2Key(egs, error); } return res; } /** * This method checks the SMask value of the ExtGState dictionary. The Soft * Mask is optional but must be "None" if it is present. * * @param egs * the Graphic state to check * @param error * the list of error to update if the validation fails. * @return true if SMask is missing or equals to None */ private boolean checkSoftMask(COSDictionary egs, List<ValidationError> error) { COSBase smVal = egs.getItem(COSName.getPDFName(TRANSPARENCY_DICTIONARY_KEY_SOFT_MASK)); if (smVal != null) { // ---- Soft Mask is valid only if it is a COSName equals to None if (!(smVal instanceof COSName && TRANSPARENCY_DICTIONARY_VALUE_SOFT_MASK_NONE.equals(((COSName) smVal).getName()))) { error.add( new ValidationError(ERROR_TRANSPARENCY_EXT_GS_SOFT_MASK, "SoftMask must be null or None")); return false; } } return true; } /** * This method checks the BM value of the ExtGState dictionary. The Blend Mode * is optional but must be "Normal" or "Compatible" if it is present. * * @param egs * the graphic state to check * @param error * the list of error to update if the validation fails. * @return true if BM is missing or equals to "Normal" or "Compatible" */ private boolean checkBlendMode(COSDictionary egs, List<ValidationError> error) { COSBase bmVal = egs.getItem(COSName.getPDFName(TRANSPARENCY_DICTIONARY_KEY_BLEND_MODE)); if (bmVal != null) { // ---- Blend Mode is valid only if it is equals to Normal or Compatible if (!(bmVal instanceof COSName && (TRANSPARENCY_DICTIONARY_VALUE_BM_NORMAL.equals(((COSName) bmVal).getName()) || TRANSPARENCY_DICTIONARY_VALUE_BM_COMPATIBLE.equals(((COSName) bmVal).getName())))) { error.add(new ValidationError(ERROR_TRANSPARENCY_EXT_GS_BLEND_MODE, "BlendMode value isn't valid (only Normal and Compatible are authorized)")); return false; } } return true; } /** * This method checks the "CA" and "ca" values of the ExtGState dictionary. * They are optional but must be 1.0 if they are present. * * @param egs * the graphic state to check * @param error * the list of error to update if the validation fails. * @return true if CA/ca is missing or equals to 1.0 */ private boolean checkCA(COSDictionary egs, List<ValidationError> error) { COSBase uCA = egs.getItem(COSName.getPDFName(TRANSPARENCY_DICTIONARY_KEY_UPPER_CA)); COSBase lCA = egs.getItem(COSName.getPDFName(TRANSPARENCY_DICTIONARY_KEY_LOWER_CA)); if (uCA != null) { // ---- If CA is present only the value 1.0 is authorized Float fca = COSUtils.getAsFloat(uCA, cDoc); Integer ica = COSUtils.getAsInteger(uCA, cDoc); if (!(fca != null && fca == 1.0f) && !(ica != null && ica == 1)) { error.add(new ValidationError(ERROR_TRANSPARENCY_EXT_GS_CA, "CA entry in a ExtGState is invalid")); return false; } } if (lCA != null) { // ---- If ca is present only the value 1.0 is authorized Float fca = COSUtils.getAsFloat(lCA, cDoc); Integer ica = COSUtils.getAsInteger(lCA, cDoc); if (!(fca != null && fca == 1.0f) && !(ica != null && ica == 1)) { error.add( new ValidationError(ERROR_TRANSPARENCY_EXT_GS_CA, "ca entry in a ExtGState is invalid.")); return false; } } return true; } /** * Check the TR entry. A valid ExtGState hasn't TR entry. * * @param egs * the graphic state to check * @param error * the list of error to update if the validation fails. * @return true if TR entry is missing, false otherwise. */ protected boolean checkTRKey(COSDictionary egs, List<ValidationError> error) { if (egs.getItem(COSName.getPDFName("TR")) != null) { error.add(new ValidationError(ValidationConstants.ERROR_GRAPHIC_UNEXPECTED_KEY, "No TR key expected in Extended graphics state")); return false; } return true; } /** * Check the TR2 entry. A valid ExtGState hasn't TR2 entry or a TR2 entry * equals to "default". * * @param egs * the graphic state to check * @param error * the list of error to update if the validation fails. * @return true if TR2 entry is missing or equals to "default", false * otherwise. */ protected boolean checkTR2Key(COSDictionary egs, List<ValidationError> error) { if (egs.getItem(COSName.getPDFName("TR2")) != null) { String s = egs.getNameAsString(COSName.getPDFName("TR2")); if (!"default".equals(s)) { error.add(new ValidationError(ValidationConstants.ERROR_GRAPHIC_UNEXPECTED_VALUE_FOR_KEY, "TR2 key only expect 'default' value, not '" + s + "'")); return false; } } return true; } /** * Check the RI entry of the Graphic State. If the rendering intent entry is * present, the value must be one of the four values defined in the PDF * reference. (@see net.awl.edoc.pdfa.validation.utils.RenderingIntents) * * @param egs * the graphic state to check * @param error * the list of error to update if the validation fails. * @return true if RI entry is valid, false otherwise. */ protected boolean checkRIKey(COSDictionary egs, List<ValidationError> error) { String rendenringIntent = egs.getNameAsString(COSName.getPDFName("RI")); if (rendenringIntent != null && !"".equals(rendenringIntent) && !RenderingIntents.contains(rendenringIntent)) { error.add(new ValidationError(ValidationConstants.ERROR_GRAPHIC_UNEXPECTED_VALUE_FOR_KEY, "Invalid rendering intent value in Extended graphics state")); return false; } return true; } }