fix(placeholder): generate placeholderId using name and object reference

Reason: according to the PDF specification, a name only needs to be unique within a specific resource list, and multiple resource lists may exist within a document

6 files changed, 38 insertions, 12 deletions

diff --git a/pdf-as-pdfbox-2/src/main/java/at/gv/egiz/pdfas/lib/impl/pdfbox2/placeholder/SignaturePlaceholderExtractor.java b/pdf-as-pdfbox-2/src/main/java/at/gv/egiz/pdfas/lib/impl/pdfbox2/placeholder/SignaturePlaceholderExtractor.java
index 011eac89..8716603b 100644
--- a/pdf-as-pdfbox-2/src/main/java/at/gv/egiz/pdfas/lib/impl/pdfbox2/placeholder/SignaturePlaceholderExtractor.java
+++ b/pdf-as-pdfbox-2/src/main/java/at/gv/egiz/pdfas/lib/impl/pdfbox2/placeholder/SignaturePlaceholderExtractor.java
@@ -65,7 +65,9 @@ import org.apache.pdfbox.contentstream.PDFStreamEngine;
 import org.apache.pdfbox.contentstream.operator.Operator;
 import org.apache.pdfbox.contentstream.operator.OperatorProcessor;
 import org.apache.pdfbox.cos.COSBase;
+import org.apache.pdfbox.cos.COSDictionary;
 import org.apache.pdfbox.cos.COSName;
+import org.apache.pdfbox.cos.COSObject;
 import org.apache.pdfbox.pdmodel.PDDocument;
 import org.apache.pdfbox.pdmodel.PDPage;
 import org.apache.pdfbox.pdmodel.graphics.PDXObject;
@@ -243,7 +245,7 @@ public class SignaturePlaceholderExtractor extends PDFStreamEngine implements Pl
                        
             try {
               data.setTablePos(new TablePos(posString));
-              data.setPlaceholderName(objectName.getName());
+              data.setPlaceholderName(buildUniqueObjectName(objectName));
               log.debug("Found Placeholder at: {}", data.toString());
               placeholders.add(data);
               
@@ -291,7 +293,31 @@ public class SignaturePlaceholderExtractor extends PDFStreamEngine implements Pl
     
   }
   
+  /**
+   * Builds unique placeholderId from PDF element.
+   * 
+   * @param name PDF element name
+   * @return unique identifier
+   */
+  private String buildUniqueObjectName(COSName name)
+  {
+      COSDictionary dict = getResources().getCOSObject().getCOSDictionary(COSName.XOBJECT);
+      if (dict == null)
+      {
+          return name.getName();
+          
+      }
+      
+      COSBase base = dict.getItem(name);
+      if (base instanceof COSObject)
+      {                            
+          return name.getName() + "_" + String.valueOf(((COSObject) base).getObjectNumber());      
+          
+      }
 
+      return name.getName();
+      
+  }
   
   private SignaturePlaceholderData matchPlaceholderPage(
       List<SignaturePlaceholderData> placeholders, String placeholderId, int matchMode) {
diff --git a/pdf-as-pdfbox-2/src/test/java/at/gv/egiz/pdfas/lib/testpdfbox/PDFBoxPlaceholderExtractorTest.java b/pdf-as-pdfbox-2/src/test/java/at/gv/egiz/pdfas/lib/testpdfbox/PDFBoxPlaceholderExtractorTest.java
index 80e3eb4d..d0c215ae 100644
--- a/pdf-as-pdfbox-2/src/test/java/at/gv/egiz/pdfas/lib/testpdfbox/PDFBoxPlaceholderExtractorTest.java
+++ b/pdf-as-pdfbox-2/src/test/java/at/gv/egiz/pdfas/lib/testpdfbox/PDFBoxPlaceholderExtractorTest.java
@@ -21,7 +21,7 @@ public class PDFBoxPlaceholderExtractorTest {
   @SneakyThrows
   public void nextPlaceholder() {
     SignaturePlaceholderData result = getNextSignaturePlaceHolder("/data/platzhalter_en_de_test.pdf");
-    assertEquals("Im48", result.getPlaceholderName());
+    assertEquals("Im48_48", result.getPlaceholderName());
 
   }
 
diff --git a/pdf-as-pdfbox-2/src/test/java/at/gv/egiz/pdfas/lib/testpdfbox/SignatureFieldsAndPlaceHolderExtractorTest.java b/pdf-as-pdfbox-2/src/test/java/at/gv/egiz/pdfas/lib/testpdfbox/SignatureFieldsAndPlaceHolderExtractorTest.java
index 0ed05eb5..2e5e475c 100644
--- a/pdf-as-pdfbox-2/src/test/java/at/gv/egiz/pdfas/lib/testpdfbox/SignatureFieldsAndPlaceHolderExtractorTest.java
+++ b/pdf-as-pdfbox-2/src/test/java/at/gv/egiz/pdfas/lib/testpdfbox/SignatureFieldsAndPlaceHolderExtractorTest.java
@@ -29,12 +29,12 @@ public class SignatureFieldsAndPlaceHolderExtractorTest {
   @Test
   public void notSigned(){
     SignaturePlaceholderData result = getNextSignaturePlaceHolder(getPath("new_qr_2-2.pdf"));
-    Assert.assertEquals("Image5",result.getPlaceholderName());
+    Assert.assertEquals("Image5_5",result.getPlaceholderName());
   }
   @Test
   public void signedOnce(){
     SignaturePlaceholderData result = getNextSignaturePlaceHolder(getPath("new_qr_2_signed.pdf"));
-    Assert.assertEquals("Image8",result.getPlaceholderName());
+    Assert.assertEquals("Image8_8",result.getPlaceholderName());
   }
   @Test
   public void signedTwice(){
@@ -56,7 +56,7 @@ public class SignatureFieldsAndPlaceHolderExtractorTest {
   @Test
   public void firstQrCodeOnUnsignedDoc() {
     SignaturePlaceholderData result = getNextSignaturePlaceHolder(getPath("new_qr_2-2.pdf"));
-    Assert.assertEquals("Image5",result.getPlaceholderName());
+    Assert.assertEquals("Image5_5",result.getPlaceholderName());
     
   }
   
@@ -66,28 +66,28 @@ public class SignatureFieldsAndPlaceHolderExtractorTest {
     Assert.assertEquals(null,result);
 
     result = getNextSignaturePlaceHolder(getPath("new_qr_2_signed.pdf"));
-    Assert.assertEquals("Image8",result.getPlaceholderName());
+    Assert.assertEquals("Image8_8",result.getPlaceholderName());
 
     result = getNextSignaturePlaceHolder(getPath("new_qr_2-2.pdf"));
-    Assert.assertEquals("Image5",result.getPlaceholderName());
+    Assert.assertEquals("Image5_5",result.getPlaceholderName());
 
     result = getNextSignaturePlaceHolder(getPath("new_qr_2-2.pdf"));
-    Assert.assertEquals("Image5",result.getPlaceholderName());
+    Assert.assertEquals("Image5_5",result.getPlaceholderName());
 
     result = getNextSignaturePlaceHolder(getPath("new_qr_2-2.pdf"));
-    Assert.assertEquals("Image5",result.getPlaceholderName());
+    Assert.assertEquals("Image5_5",result.getPlaceholderName());
 
     result = getNextSignaturePlaceHolder(getPath("new_qr_2_signed.pdf"));
-    Assert.assertEquals("Image8",result.getPlaceholderName());
+    Assert.assertEquals("Image8_8",result.getPlaceholderName());
 
     result = getNextSignaturePlaceHolder(getPath("new_qr_2_signed_signed_signed.pdf"));
     Assert.assertEquals(null,result);
 
     result = getNextSignaturePlaceHolder(getPath("new_qr_2-2.pdf"));
-    Assert.assertEquals("Image5",result.getPlaceholderName());
+    Assert.assertEquals("Image5_5",result.getPlaceholderName());
 
     result = getNextSignaturePlaceHolder(getPath("new_qr_2_signed.pdf"));
-    Assert.assertEquals("Image8",result.getPlaceholderName());
+    Assert.assertEquals("Image8_8",result.getPlaceholderName());
   }
   @Test
   public void notSignedAndNoFields(){
diff --git a/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed.pdf b/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed.pdf
index be6fdddb..c3a53b23 100644
--- a/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed.pdf
+++ b/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed.pdf
diff --git a/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed_signed.pdf b/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed_signed.pdf
index ee0f140f..1b831a73 100644
--- a/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed_signed.pdf
+++ b/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed_signed.pdf
diff --git a/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed_signed_signed.pdf b/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed_signed_signed.pdf
index 34769dd0..6468ada7 100644
--- a/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed_signed_signed.pdf
+++ b/pdf-as-pdfbox-2/src/test/resources/new_qr_2_signed_signed_signed.pdf