1 files changed, 30 insertions, 6 deletions
diff --git a/pdf-as-lib/src/main/java/at/gv/egiz/pdfas/lib/api/sign/IPlainSigner.java b/pdf-as-lib/src/main/java/at/gv/egiz/pdfas/lib/api/sign/IPlainSigner.java
index 0ad40cc4..70945678 100644
--- a/pdf-as-lib/src/main/java/at/gv/egiz/pdfas/lib/api/sign/IPlainSigner.java
+++ b/pdf-as-lib/src/main/java/at/gv/egiz/pdfas/lib/api/sign/IPlainSigner.java
@@ -1,17 +1,41 @@
 package at.gv.egiz.pdfas.lib.api.sign;
 
 import iaik.x509.X509Certificate;
-
-import java.io.IOException;
-
-import org.apache.pdfbox.cos.COSName;
-import org.apache.pdfbox.exceptions.SignatureException;
-
 import at.gv.egiz.pdfas.common.exceptions.PdfAsException;
 
+/**
+ * Signer interface
+ * 
+ * PDF-AS uses an IPlainSigner instance to create the signature. Also custom IPlainSigner
+ * may be used to sign PDF-AS documents.
+ */
 public interface IPlainSigner {
+	
+	/**
+	 * Gets the signing certificate
+	 * @return
+	 * @throws PdfAsException
+	 */
 	public X509Certificate getCertificate() throws PdfAsException;
+	
+	/**
+	 * Sign the document
+	 * @param input
+	 * @param byteRange
+	 * @return
+	 * @throws PdfAsException
+	 */
     public byte[] sign(byte[] input, int[] byteRange) throws PdfAsException;
+    
+    /**
+     * Gets the PDF Subfilter for this signer
+     * @return
+     */
     public String getPDFSubFilter();
+    
+    /**
+     * Gets the PDF Filter for this signer
+     * @return
+     */
     public String getPDFFilter();
 }