XMP metadata generation from the PDFInfo object now conforms to PDF/A-1 (6.7.3 in ISO 19005-1:2005(E)).

On PDFDocument, it is now possible to set the PDF-A mode which triggers conformance checks where necessary.
The first PDF/A-1b conformance checks are now in the code. When conformance problems are detected, the new PDFConformanceException (subclass of RuntimeException since this would be a programmer error) is thrown.
PDF Renderer got a setting (through rendering options and XML configuration) to set the PDF/A-1 mode. Default is "disabled".

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@378560 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/fop/fo/extensions/xmp/XMPConstants.java

@@ -35,4 +35,7 @@ public interface XMPConstants {
     /** Namespace URI for the XMP Basic Schema */
     String XMP_BASIC_NAMESPACE = "http://ns.adobe.com/xap/1.0/";
     
+    /** Namespace URI for the Adobe PDF Schema */
+    String ADOBE_PDF_NAMESPACE = "http://ns.adobe.com/pdf/1.3/";
+    
 }

src/java/org/apache/fop/pdf/PDFAMode.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2006 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.
+ */
+
+/* $Id$ */
+
+package org.apache.fop.pdf;
+
+/** Enum class for PDF/A modes. */
+public final class PDFAMode {
+
+    /** PDF/A disabled */
+    public static final PDFAMode DISABLED = new PDFAMode("PDF/A disabled");
+    /** PDF/A-1a enabled */
+    public static final PDFAMode PDFA_1A = new PDFAMode("PDF/A-1a");
+    /** PDF/A-1b enabled */
+    public static final PDFAMode PDFA_1B = new PDFAMode("PDF/A-1b");
+    
+    private String name;
+
+    /**
+     * Constructor to add a new named item.
+     * @param name Name of the item.
+     */
+    private PDFAMode(String name) {
+        this.name = name;
+    }
+
+    /** @return the name of the enum */
+    public String getName() {
+        return this.name;
+    }
+    
+    /** @return true if this mode obey the restrictions established by PDF/A-1b. */
+    public boolean isPDFA1LevelB() {
+        return (this != DISABLED);
+    }
+    
+    /**
+     * Returns the mode enum object given a String.
+     * @param s the string
+     * @return the PDFAMode enum object (DISABLED will be returned if no match is found)
+     */
+    public static PDFAMode valueOf(String s) {
+        if (PDFA_1A.getName().equalsIgnoreCase(s)) {
+            return PDFA_1A;
+        } else if (PDFA_1B.getName().equalsIgnoreCase(s)) {
+            return PDFA_1B;
+        } else {
+            return DISABLED;
+        }
+    }
+    
+    /** @see java.lang.Object#toString() */
+    public String toString() {
+        return name;
+    }
+    
+}

src/java/org/apache/fop/pdf/PDFConformanceException.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2006 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.
+ */
+
+/* $Id$ */
+
+package org.apache.fop.pdf;
+
+/**
+ * RuntimeException descendant indicating a conformance problem during PDF generation. This
+ * exception will be throws, for example, when PDF/A-1 Level B conformance is activated but the
+ * PDF version produced is not PDF 1.4 as mandated by ISO 19005-1:2005(E).
+ */
+public class PDFConformanceException extends RuntimeException {
+
+    /**
+     * Constructs an PDFConformanceException with no detail message.
+     * A detail message is a String that describes this particular exception.
+     */
+    public PDFConformanceException() {
+        super();
+    }
+    
+    /**
+     * Constructs an PDFConformanceException with the specified detail
+     * message. A detail message is a String that describes this particular
+     * exception.
+     * @param message the String that contains a detailed message
+     */
+    public PDFConformanceException(String message) {
+        super(message);
+    }
+    
+}

src/java/org/apache/fop/pdf/PDFDocument.java

@@ -58,10 +58,6 @@ import org.apache.commons.logging.LogFactory;
 public class PDFDocument {
 
     private static final Integer LOCATION_PLACEHOLDER = new Integer(0);
-    /**
-     * the version of PDF supported which is 1.4
-     */
-    protected static final String PDF_VERSION = "1.4";
     
     /** Integer constant to represent PDF 1.3 */
     public static final int PDF_VERSION_1_3 = 3;
@@ -107,6 +103,12 @@ public class PDFDocument {
     /** Indicates what PDF version is active */
     protected int pdfVersion = PDF_VERSION_1_4;
     
+    /**
+     * Indicates the PDF/A-1 mode currently active. Defaults to "no restrictions", i.e. 
+     * PDF/A-1 not active.
+     */
+    protected PDFAMode pdfAMode = PDFAMode.DISABLED;
+    
     /**
      * the /Root object
      */
@@ -250,6 +252,35 @@ public class PDFDocument {
         return this.pdfVersion;
     }
     
+    /** @return the String representing the active PDF version */
+    public String getPDFVersionString() {
+        switch (getPDFVersion()) {
+        case PDF_VERSION_1_3:
+            return "1.3";
+        case PDF_VERSION_1_4:
+            return "1.4";
+        default:
+            throw new IllegalStateException("Unsupported PDF version selected");
+        }
+    }
+
+    /** @return the PDF/A mode currently active. */
+    public PDFAMode getPDFAMode() {
+        return this.pdfAMode;
+    }
+    
+    /**
+     * Sets the active PDF/A mode. This must be set immediately after calling the constructor so
+     * the checks will be activated.
+     * @param mode one of the PDFAMode constants
+     */
+    public void setPDFAMode(PDFAMode mode) {
+        if (mode == null) {
+            throw new NullPointerException("mode must not be null");
+        }
+        this.pdfAMode = mode;
+    }
+    
     /**
      * Returns the factory for PDF objects.
      * @return PDFFactory the factory
@@ -474,8 +505,10 @@ public class PDFDocument {
      * @param params The encryption parameters for the pdf file
      */
     public void setEncryption(PDFEncryptionParams params) {
-        this.encryption =
-            PDFEncryptionManager.newInstance(++this.objectcount, params);
+        if (getPDFAMode().isPDFA1LevelB()) {
+            throw new PDFConformanceException("PDF/A-1 doesn't allow encrypted PDFs");
+        }
+        this.encryption = PDFEncryptionManager.newInstance(++this.objectcount, params);
         ((PDFObject)this.encryption).setDocument(this);
         if (encryption != null) {
             /**@todo this cast is ugly. PDFObject should be transformed to an interface. */
@@ -824,13 +857,16 @@ public class PDFDocument {
     public void outputHeader(OutputStream stream) throws IOException {
         this.position = 0;
 
-        byte[] pdf = ("%PDF-" + PDF_VERSION + "\n").getBytes();
+        if (getPDFAMode().isPDFA1LevelB() && getPDFVersion() != PDF_VERSION_1_4) {
+            throw new PDFConformanceException("PDF version must be 1.4 for " + getPDFAMode());
+        }
+        
+        byte[] pdf = ("%PDF-" + getPDFVersionString() + "\n").getBytes();
         stream.write(pdf);
         this.position += pdf.length;
 
         // output a binary comment as recommended by the PDF spec (3.4.1)
-        byte[] bin =
-            {
+        byte[] bin = {
                 (byte)'%',
                 (byte)0xAA,
                 (byte)0xAB,

src/java/org/apache/fop/pdf/PDFInfo.java

@@ -44,6 +44,11 @@ public class PDFInfo extends PDFObject {
      */
     private String creator;
 
+    /** @return the producer of the document or null if not set */
+    public String getProducer() {
+        return this.producer;
+    }
+    
     /**
      * set the producer string
      *
@@ -110,7 +115,7 @@ public class PDFInfo extends PDFObject {
     }
 
     /** @return the keywords for the document or null if not set */
-    public String getKeyword() {
+    public String getKeywords() {
         return this.keywords;
     }
     

src/java/org/apache/fop/pdf/PDFMetadata.java

@@ -23,6 +23,7 @@ import java.io.OutputStream;
 import java.text.DateFormat;
 import java.text.SimpleDateFormat;
 import java.util.Date;
+import java.util.TimeZone;
 
 import javax.xml.transform.OutputKeys;
 import javax.xml.transform.Transformer;
@@ -32,7 +33,6 @@ import javax.xml.transform.TransformerFactory;
 import javax.xml.transform.dom.DOMSource;
 import javax.xml.transform.stream.StreamResult;
 
-import org.apache.fop.apps.FOUserAgent;
 import org.apache.fop.fo.ElementMapping;
 import org.apache.fop.fo.extensions.xmp.XMPConstants;
 import org.w3c.dom.DOMImplementation;
@@ -127,6 +127,11 @@ public class PDFMetadata extends PDFStream {
     /** @see org.apache.fop.pdf.AbstractPDFStream#buildStreamDict(String) */
     protected String buildStreamDict(String lengthEntry) {
         final String filterEntry = getFilterList().buildFilterDictEntries();
+        if (getDocumentSafely().getPDFAMode().isPDFA1LevelB() 
+                && filterEntry != null && filterEntry.length() > 0) {
+            throw new PDFConformanceException(
+                    "The Filter key is prohibited when PDF/A-1 is active");
+        }
         final StringBuffer sb = new StringBuffer(128);
         sb.append(getObjectID());
         sb.append("<< ");
@@ -153,7 +158,8 @@ public class PDFMetadata extends PDFStream {
         Element desc, el;
         PDFInfo info = pdfDoc.getInfo();
         DateFormat pseudoISO8601DateFormat = new SimpleDateFormat(
-            "yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'SSS");
+            "yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'SSS'Z'");
+        pseudoISO8601DateFormat.setTimeZone(TimeZone.getTimeZone("GMT+00"));
         
         //Set creation date if not available, yet
         if (info.getCreationDate() == null) {
@@ -161,9 +167,12 @@ public class PDFMetadata extends PDFStream {
             info.setCreationDate(d);
         }
 
+        final String xmlns = "http://www.w3.org/2000/xmlns/";
+        
         //Dublin Core
         desc = doc.createElementNS(XMPConstants.RDF_NAMESPACE, "rdf:Description");
         desc.setAttribute("about", "");
+        desc.setAttributeNS(xmlns, "xmlns:dc", XMPConstants.DUBLIN_CORE_NAMESPACE);
         rdf.appendChild(desc);
         if (info.getAuthor() != null) {
             el = doc.createElementNS(XMPConstants.DUBLIN_CORE_NAMESPACE, "dc:creator");
@@ -187,6 +196,7 @@ public class PDFMetadata extends PDFStream {
         //XMP Basic Schema
         desc = doc.createElementNS(XMPConstants.RDF_NAMESPACE, "rdf:Description");
         desc.setAttribute("about", "");
+        desc.setAttributeNS(xmlns, "xmlns:xmp", XMPConstants.XMP_BASIC_NAMESPACE);
         rdf.appendChild(desc);
         el = doc.createElementNS(XMPConstants.XMP_BASIC_NAMESPACE, "xmp:createDate");
         desc.appendChild(el);
@@ -197,6 +207,24 @@ public class PDFMetadata extends PDFStream {
             el.appendChild(doc.createTextNode(info.getCreator()));
         }
         
+        //Adobe PDF Schema
+        desc = doc.createElementNS(XMPConstants.RDF_NAMESPACE, "rdf:Description");
+        desc.setAttribute("about", "");
+        desc.setAttributeNS(xmlns, "xmlns:pdf", XMPConstants.ADOBE_PDF_NAMESPACE);
+        rdf.appendChild(desc);
+        if (info.getKeywords() != null) {
+            el = doc.createElementNS(XMPConstants.ADOBE_PDF_NAMESPACE, "pdf:Keywords");
+            desc.appendChild(el);
+            el.appendChild(doc.createTextNode(info.getKeywords()));
+        }
+        if (info.getProducer() != null) {
+            el = doc.createElementNS(XMPConstants.ADOBE_PDF_NAMESPACE, "pdf:Producer");
+            desc.appendChild(el);
+            el.appendChild(doc.createTextNode(info.getProducer()));
+        }
+        el = doc.createElementNS(XMPConstants.ADOBE_PDF_NAMESPACE, "pdf:PDFVersion");
+        desc.appendChild(el);
+        el.appendChild(doc.createTextNode(pdfDoc.getPDFVersionString()));
         
         return doc;
     }

src/java/org/apache/fop/render/pdf/PDFRenderer.java

@@ -62,6 +62,7 @@ import org.apache.fop.fonts.FontSetup;
 import org.apache.fop.image.FopImage;
 import org.apache.fop.image.ImageFactory;
 import org.apache.fop.image.XMLImage;
+import org.apache.fop.pdf.PDFAMode;
 import org.apache.fop.pdf.PDFAnnotList;
 import org.apache.fop.pdf.PDFColor;
 import org.apache.fop.pdf.PDFDocument;
@@ -109,6 +110,9 @@ public class PDFRenderer extends AbstractPathOrientedRenderer {
      */
     public static final String MIME_TYPE = MimeConstants.MIME_PDF;
 
+    /** Rendering Options key for the PDF/A mode. */
+    public static final String PDF_A_MODE = "pdf-a-mode";
+
     /** Controls whether comments are written to the PDF stream. */
     protected static final boolean WRITE_COMMENTS = true;
     
@@ -117,6 +121,9 @@ public class PDFRenderer extends AbstractPathOrientedRenderer {
      */
     protected PDFDocument pdfDoc;
 
+    /** the PDF/A mode (Default: disabled) */
+    protected PDFAMode pdfAMode = PDFAMode.DISABLED;
+    
     /**
      * Map of pages using the PageViewport as the key
      * this is used for prepared pages that cannot be immediately
@@ -230,6 +237,11 @@ public class PDFRenderer extends AbstractPathOrientedRenderer {
         } else {
             this.fontList.addAll(cfgFonts);
         }
+        
+        String s = cfg.getChild(PDF_A_MODE, true).getValue(null);
+        if (s != null) {
+            this.pdfAMode = PDFAMode.valueOf(s);
+        }
     }
 
     /**
@@ -237,6 +249,10 @@ public class PDFRenderer extends AbstractPathOrientedRenderer {
      */
     public void setUserAgent(FOUserAgent agent) {
         super.setUserAgent(agent);
+        String s = (String)agent.getRendererOptions().get(PDF_A_MODE);
+        if (s != null) {
+            this.pdfAMode = PDFAMode.valueOf(s);
+        }
     }
 
     /**
@@ -249,6 +265,7 @@ public class PDFRenderer extends AbstractPathOrientedRenderer {
         ostream = stream;
         this.pdfDoc = new PDFDocument(
                 userAgent.getProducer() != null ? userAgent.getProducer() : "");
+        this.pdfDoc.setPDFAMode(this.pdfAMode);
         this.pdfDoc.setCreator(userAgent.getCreator());
         this.pdfDoc.setCreationDate(userAgent.getCreationDate());
         this.pdfDoc.getInfo().setAuthor(userAgent.getAuthor());