From: Daniel Drake <dsd@gentoo.org>

Exception handling is expensive, lets avoid it where possible.

Index: Document/Field.cs
===================================================================
RCS file: /cvs/gnome/beagle/beagled/Lucene.Net/Document/Field.cs,v
retrieving revision 1.3
diff -u -B -p -r1.3 Field.cs
--- Document/Field.cs	6 Oct 2005 19:29:55 -0000	1.3
+++ Document/Field.cs	16 Oct 2005 19:51:18 -0000
@@ -299,14 +299,7 @@ namespace Lucene.Net.Documents
         /// </summary>
         public System.String StringValue()
         {
-            try
-            {
-                return (System.String) fieldsData;
-            }
-            catch (System.InvalidCastException ignore)
-            {
-                return null;
-            }
+			return fieldsData as System.String;
         }
 		
         /// <summary>The value of the field as a Reader, or null.  If null, the String value
@@ -315,14 +308,7 @@ namespace Lucene.Net.Documents
         /// </summary>
         public System.IO.TextReader ReaderValue()
         {
-            try
-            {
-                return (System.IO.TextReader) fieldsData;
-            }
-            catch (System.InvalidCastException ignore)
-            {
-                return null;
-            }
+			return fieldsData as System.IO.TextReader;
         }
 		
         /// <summary>The value of the field in Binary, or null.  If null, the Reader or
@@ -331,14 +317,7 @@ namespace Lucene.Net.Documents
         /// </summary>
         public byte[] BinaryValue()
         {
-            try
-            {
-                return (byte[]) fieldsData;
-            }
-            catch (System.InvalidCastException ignore)
-            {
-                return null;
-            }
+			return fieldsData as byte[];
         }
 		
         /// <summary> Create a field by specifying its name, value and how it will
@@ -740,4 +719,4 @@ namespace Lucene.Net.Documents
             return result.ToString();
         }
     }
-}
\ No newline at end of file
+}
Index: Index/FieldInfos.cs
===================================================================
RCS file: /cvs/gnome/beagle/beagled/Lucene.Net/Index/FieldInfos.cs,v
retrieving revision 1.4
diff -u -B -p -r1.4 FieldInfos.cs
--- Index/FieldInfos.cs	6 Oct 2005 19:29:55 -0000	1.4
+++ Index/FieldInfos.cs	16 Oct 2005 19:51:18 -0000
@@ -196,16 +196,9 @@ namespace Lucene.Net.Index
 		
 		public int FieldNumber(System.String fieldName)
 		{
-            try
-            {
-                FieldInfo fi = FieldInfo(fieldName);
-                if (fi != null)
-                    return fi.number;
-            }
-            catch (System.IndexOutOfRangeException ioobe)
-            {
-                return - 1;
-            }
+			FieldInfo fi = FieldInfo(fieldName);
+            if (fi != null)
+                return fi.number;
             return - 1;
         }
 		
@@ -224,14 +217,11 @@ namespace Lucene.Net.Index
         /// </returns>
         public System.String FieldName(int fieldNumber)
         {
-            try
-            {
-                return FieldInfo(fieldNumber).name;
-            }
-            catch (System.NullReferenceException npe)
-            {
-                return "";
-            }
+			FieldInfo info = FieldInfo(fieldNumber);
+			if (info == null)
+				return "";
+			else
+                return info.name;
         }
 		
         /// <summary> Return the fieldinfo object referenced by the fieldNumber.</summary>
@@ -242,19 +232,12 @@ namespace Lucene.Net.Index
         /// </returns>
         public FieldInfo FieldInfo(int fieldNumber)
 		{
-            if (fieldNumber < 0)
+            if (fieldNumber < 0 || fieldNumber >= byNumber.Count)
             {
                 return null;
             }
 
-            try
-            {
-                return (FieldInfo) byNumber[fieldNumber];
-            }
-            catch (System.IndexOutOfRangeException ioobe)
-            {
-                return null;
-            }
+            return (FieldInfo) byNumber[fieldNumber];
         }
 		
 		public int Size()
@@ -324,4 +307,4 @@ namespace Lucene.Net.Index
 			}
 		}
 	}
-}
\ No newline at end of file
+}