public PdfDocument.Meta GetDocumentMeta(PdfDocument doc)
 {
     lock (Obj)
     {
         var meta = new PdfDocument.Meta
         {
             Title        = Object.GetObject <Java.Lang.String>(JNIEnv.Handle, GetDocumentMetaText(JNIEnv.Handle, IntPtr.Zero, doc.MNativeDocPtr, tag: new Java.Lang.String("Title").Handle), JniHandleOwnership.TransferLocalRef).ToString(),
             Author       = Object.GetObject <Java.Lang.String>(JNIEnv.Handle, GetDocumentMetaText(JNIEnv.Handle, IntPtr.Zero, doc.MNativeDocPtr, tag: new Java.Lang.String("Author").Handle), JniHandleOwnership.TransferLocalRef).ToString(),
             Subject      = Object.GetObject <Java.Lang.String>(JNIEnv.Handle, GetDocumentMetaText(JNIEnv.Handle, IntPtr.Zero, doc.MNativeDocPtr, tag: new Java.Lang.String("Subject").Handle), JniHandleOwnership.TransferLocalRef).ToString(),
             Keywords     = Object.GetObject <Java.Lang.String>(JNIEnv.Handle, GetDocumentMetaText(JNIEnv.Handle, IntPtr.Zero, doc.MNativeDocPtr, tag: new Java.Lang.String("Keywords").Handle), JniHandleOwnership.TransferLocalRef).ToString(),
             Creator      = Object.GetObject <Java.Lang.String>(JNIEnv.Handle, GetDocumentMetaText(JNIEnv.Handle, IntPtr.Zero, doc.MNativeDocPtr, tag: new Java.Lang.String("Creator").Handle), JniHandleOwnership.TransferLocalRef).ToString(),
             Producer     = Object.GetObject <Java.Lang.String>(JNIEnv.Handle, GetDocumentMetaText(JNIEnv.Handle, IntPtr.Zero, doc.MNativeDocPtr, tag: new Java.Lang.String("Producer").Handle), JniHandleOwnership.TransferLocalRef).ToString(),
             CreationDate = Object.GetObject <Java.Lang.String>(JNIEnv.Handle, GetDocumentMetaText(JNIEnv.Handle, IntPtr.Zero, doc.MNativeDocPtr, tag: new Java.Lang.String("CreationDate").Handle), JniHandleOwnership.TransferLocalRef).ToString(),
             ModDate      = Object.GetObject <Java.Lang.String>(JNIEnv.Handle, GetDocumentMetaText(JNIEnv.Handle, IntPtr.Zero, doc.MNativeDocPtr, tag: new Java.Lang.String("ModDate").Handle), JniHandleOwnership.TransferLocalRef).ToString()
         };
         return(meta);
     }
 }