Mark some internal functions as protected

@@ -93,8 +93,8 @@ class PdfAnnot extends PdfObject {
   ///
   /// @param os OutputStream to send the object to
   @override
-  void prepare() {
-    super.prepare();
+  void _prepare() {
+    super._prepare();
 
     params["/Subtype"] = PdfStream.string(subtype);
     params["/Rect"] = PdfStream.string(

@@ -24,8 +24,8 @@ class PdfArrayObject extends PdfObject {
   PdfArrayObject(PdfDocument pdfDocument, this.values) : super(pdfDocument);
 
   @override
-  void writeContent(PdfStream os) {
-    super.writeContent(os);
+  void _writeContent(PdfStream os) {
+    super._writeContent(os);
 
     os.putStringArray(values);
   }

@@ -61,8 +61,8 @@ class PdfBorder extends PdfObject {
 
   /// @param os OutputStream to send the object to
   @override
-  void writeContent(PdfStream os) {
-    super.writeContent(os);
+  void _writeContent(PdfStream os) {
+    super._writeContent(os);
 
     var data = List<PdfStream>();
     data.add(PdfStream.string("/S"));

@@ -38,8 +38,8 @@ class PdfCatalog extends PdfObject {
 
   /// @param os OutputStream to send the object to
   @override
-  void prepare() {
-    super.prepare();
+  void _prepare() {
+    super._prepare();
 
     params["/Pages"] = pdfPageList.ref();
 

@@ -130,7 +130,7 @@ class PdfDocument {
   /// completion. It is up to the caller to close the stream.
   ///
   /// @param os OutputStream to write the document to
-  void write(PdfStream os) {
+  void _write(PdfStream os) {
     PdfOutput pos = PdfOutput(os);
 
     // Write each object to the [PdfStream]. We call via the output
@@ -145,7 +145,7 @@ class PdfDocument {
 
   List<int> save() {
     PdfStream os = PdfStream();
-    write(os);
+    _write(os);
     return os.output();
   }
 }

@@ -41,8 +41,8 @@ class PdfFont extends PdfObject {
 
   /// @param os OutputStream to send the object to
   @override
-  void prepare() {
-    super.prepare();
+  void _prepare() {
+    super._prepare();
 
     params["/Subtype"] = PdfStream.string(subtype);
     params["/Name"] = PdfStream.string(name);

@@ -26,8 +26,8 @@ class PdfFontDescriptor extends PdfObject {
       : super(ttfFont.pdfDocument, "/FontDescriptor");
 
   @override
-  void prepare() {
-    super.prepare();
+  void _prepare() {
+    super._prepare();
 
     params["/FontName"] = PdfStream.string(ttfFont.baseFont);
     params["/FontFile2"] = file.ref();

@@ -38,8 +38,8 @@ class PdfFormXObject extends PdfXObject {
   }
 
   @override
-  void prepare() {
-    super.prepare();
+  void _prepare() {
+    super._prepare();
 
     // Now the resources
     /// This holds any resources for this FormXObject

@@ -77,7 +77,7 @@ class PdfImage extends PdfXObject {
   }
 
   @override
-  void prepare() {
+  void _prepare() {
     // write the pixels to the stream
     // print("Processing image ${img.width}x${img.height} pixels");
 
@@ -101,7 +101,7 @@ class PdfImage extends PdfXObject {
 
     buf.putBytes(out);
 
-    super.prepare();
+    super._prepare();
   }
 
   /// Get the name

@@ -34,8 +34,8 @@ class PdfInfo extends PdfObject {
 
   /// @param os OutputStream to send the object to
   @override
-  void prepare() {
-    super.prepare();
+  void _prepare() {
+    super._prepare();
 
     if (author != null) params["/Author"] = PdfStream.text(author);
     if (creator != null) params["/Creator"] = PdfStream.text(creator);

@@ -50,16 +50,16 @@ class PdfObject {
   /// it's Kids, as they will be written by the calling routine.
   ///
   /// @param os OutputStream to send the object to
-  void write(PdfStream os) {
-    prepare();
-    writeStart(os);
-    writeContent(os);
-    writeEnd(os);
+  void _write(PdfStream os) {
+    _prepare();
+    _writeStart(os);
+    _writeContent(os);
+    _writeEnd(os);
   }
 
   /// Prepare the object to be written to the stream
   @mustCallSuper
-  void prepare() {}
+  void _prepare() {}
 
   /// The write method should call this before writing anything to the
   /// OutputStream. This will send the standard header for each object.
@@ -67,11 +67,11 @@ class PdfObject {
   /// Note: There are a few rare cases where this method is not called.
   ///
   /// @param os OutputStream to write to
-  void writeStart(PdfStream os) {
+  void _writeStart(PdfStream os) {
     os.putString("$objser $objgen obj\n");
   }
 
-  void writeContent(PdfStream os) {
+  void _writeContent(PdfStream os) {
     if (params.length > 0) {
       os.putDictionary(params);
       os.putString("\n");
@@ -84,7 +84,7 @@ class PdfObject {
   /// Note: There are a few rare cases where this method is not called.
   ///
   /// @param os OutputStream to write to
-  void writeEnd(PdfStream os) {
+  void _writeEnd(PdfStream os) {
     os.putString("endobj\n");
   }
 

@@ -38,8 +38,8 @@ class PdfObjectStream extends PdfObject {
   List<int> _data;
 
   @override
-  void prepare() {
-    super.prepare();
+  void _prepare() {
+    super._prepare();
 
     if (pdfDocument.deflate != null) {
       _data = pdfDocument.deflate(buf.output());
@@ -57,8 +57,8 @@ class PdfObjectStream extends PdfObject {
   }
 
   @override
-  void writeContent(PdfStream os) {
-    super.writeContent(os);
+  void _writeContent(PdfStream os) {
+    super._writeContent(os);
 
     os.putString("stream\n");
     os.putBytes(_data);

@@ -82,8 +82,8 @@ class PdfOutline extends PdfObject {
 
   /// @param os OutputStream to send the object to
   @override
-  void prepare() {
-    super.prepare();
+  void _prepare() {
+    super._prepare();
 
     // These are for kids only
     if (parent != null) {

@@ -49,7 +49,7 @@ class PdfOutput {
     if (ob is PdfInfo) infoID = ob;
 
     offsets.add(PdfXref(ob.objser, os.offset));
-    ob.write(os);
+    ob._write(os);
   }
 
   /// This closes the Stream, writing the xref table

@@ -76,8 +76,8 @@ class PdfPage extends PdfObject {
 
   /// @param os OutputStream to send the object to
   @override
-  void prepare() {
-    super.prepare();
+  void _prepare() {
+    super._prepare();
 
     // the /Parent pages object
     params["/Parent"] = pdfDocument.pdfPageList.ref();

@@ -31,8 +31,8 @@ class PdfPageList extends PdfObject {
   PdfPage getPage(int page) => pages[page];
 
   @override
-  void prepare() {
-    super.prepare();
+  void _prepare() {
+    super._prepare();
 
     params["/Kids"] = PdfStream()..putObjectArray(pages);
     params["/Count"] = PdfStream.intNum(pages.length);

@@ -74,8 +74,8 @@ class PdfTtfFont extends PdfFont {
   }
 
   @override
-  void prepare() {
-    super.prepare();
+  void _prepare() {
+    super._prepare();
 
     params["/FirstChar"] = PdfStream.intNum(_charMin);
     params["/LastChar"] = PdfStream.intNum(_charMax);

+import 'dart:io';
+import 'dart:math';
+import 'dart:typed_data';
+
+import 'package:pdf/pdf.dart';
+import 'package:test/test.dart';
+import 'package:vector_math/vector_math_64.dart';
+
+void main() {
+  test('Pdf', () {
+    var pdf = PdfDocument();
+    var page = PdfPage(pdf, pageFormat: const PdfPageFormat(500.0, 300.0));
+
+    page.annotations.add(PdfAnnot.annotation(page, "Hello", PdfRect(100.0, 100.0, 50.0, 50.0)));
+
+    var file = File('annot.pdf');
+    file.writeAsBytesSync(pdf.save());
+  });
+}