Merge pull request #269 from plaisted/builderpool

Remove locks / SB pooling during CoreTokenScanner parsing

src/UglyToad.PdfPig.Tokenization/NumericTokenizer.cs

@@ -8,7 +8,7 @@
 
     internal class NumericTokenizer : ITokenizer
     {
-        private static readonly StringBuilderPool StringBuilderPool = new StringBuilderPool(10);
+        private readonly StringBuilder stringBuilder = new StringBuilder();
 
         private const byte Zero = 48;
         private const byte Nine = 57;
@@ -23,7 +23,7 @@
 
             if ((currentByte >= Zero && currentByte <= Nine) || currentByte == '-' || currentByte == '+' || currentByte == '.')
             {
-                characters = StringBuilderPool.Borrow();
+                characters = stringBuilder;
                 characters.Append((char)currentByte);
             }
             else
@@ -53,7 +53,7 @@
             try
             {
                 var str = characters.ToString();
-                StringBuilderPool.Return(characters);
+                characters.Clear();
 
                 switch (str)
                 {

src/UglyToad.PdfPig.Tokenization/PlainTokenizer.cs

@@ -1,11 +1,12 @@
 namespace UglyToad.PdfPig.Tokenization
 {
     using Core;
+    using System.Text;
     using Tokens;
 
     internal class PlainTokenizer : ITokenizer
     {
-        private static readonly StringBuilderPool StringBuilderPool = new StringBuilderPool(10);
+        private readonly StringBuilder stringBuilder = new StringBuilder();
 
         public bool ReadsNextByte { get; } = true;
 
@@ -18,7 +19,7 @@
                 return false;
             }
 
-            var builder = StringBuilderPool.Borrow();
+            var builder = stringBuilder;
             builder.Append((char)currentByte);
             while (inputBytes.MoveNext())
             {
@@ -39,7 +40,7 @@
             }
 
             var text = builder.ToString();
-            StringBuilderPool.Return(builder);
+            builder.Clear();
 
             switch (text)
             {

src/UglyToad.PdfPig.Tokenization/Scanner/CoreTokenScanner.cs

@@ -15,9 +15,12 @@
         private static readonly DictionaryTokenizer DictionaryTokenizer = new DictionaryTokenizer();
         private static readonly HexTokenizer HexTokenizer = new HexTokenizer();
         private static readonly NameTokenizer NameTokenizer = new NameTokenizer();
-        private static readonly NumericTokenizer NumericTokenizer = new NumericTokenizer();
-        private static readonly PlainTokenizer PlainTokenizer = new PlainTokenizer();
-        private static readonly StringTokenizer StringTokenizer = new StringTokenizer();
+
+        // NOTE: these are not thread safe so should not be static. Each instance includes a
+        // StringBuilder it re-uses.
+        private readonly PlainTokenizer PlainTokenizer = new PlainTokenizer();
+        private readonly NumericTokenizer NumericTokenizer = new NumericTokenizer();
+        private readonly StringTokenizer StringTokenizer = new StringTokenizer();
 
         private readonly ScannerScope scope;
         private readonly IInputBytes inputBytes;

src/UglyToad.PdfPig.Tokenization/StringTokenizer.cs

@@ -6,7 +6,7 @@
 
     internal class StringTokenizer : ITokenizer
     {
-        private static readonly StringBuilderPool StringBuilderPool = new StringBuilderPool(16);
+        private readonly StringBuilder stringBuilder = new StringBuilder();
         public bool ReadsNextByte { get; } = false;
 
         public bool TryTokenize(byte currentByte, IInputBytes inputBytes, out IToken token)
@@ -23,7 +23,7 @@
                 return false;
             }
 
-            var builder = StringBuilderPool.Borrow();
+            var builder = stringBuilder;
             var numberOfBrackets = 1;
             var isEscapeActive = false;
             var isLineBreaking = false;
@@ -178,7 +178,7 @@
                 encodedWith = StringToken.Encoding.Iso88591;
             }
 
-            StringBuilderPool.Return(builder);
+            builder.Clear();
 
             token = new StringToken(tokenStr, encodedWith);
 

src/UglyToad.PdfPig.Tokenization/UglyToad.PdfPig.Tokenization.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;net45;net451;net452;net46;net461;net462;net47</TargetFrameworks>
     <LangVersion>latest</LangVersion>