Exclude packages with implemetation in namespace

src/java2yaml/Configs/excludeConfigs.txt

@@ -0,0 +1 @@
+.*implementation.*

src/java2yaml/Constants/Constants.cs

@@ -17,6 +17,7 @@ public static class Constants
         public const string InputPaths = "inputPaths";
         public const string ExcludePaths = "excludePaths";
         public const string ExcludePackages = "excludePackages";
+        public const string ExcludePackagesPath = "src/java2yaml/Configs/excludeConfigs.txt";
         public const string DocletPath = "docletPath";
 
         public const string Src = @"src\";

src/java2yaml/Steps/RunJavadoc.cs

@@ -1,5 +1,6 @@
 namespace Microsoft.Content.Build.Java2Yaml
 {
+    using System;
     using System.Collections.Generic;
     using System.IO;
     using System.Linq;
@@ -8,10 +9,11 @@
 
     public class RunJavadoc : IStep
     {
+
         public RunJavadoc(string path, Package package)
         {
             RepositoryPath = path;
-            ExcludePackages = package.ExcludePackages;
+            ExcludePackages = loadExcludeRegexes(package.ExcludePackages);
         }
 
         public string StepName => "RunJavadoc";
@@ -21,6 +23,7 @@ public RunJavadoc(string path, Package package)
 
         private static ConfigModel _config;
 
+
         public Task RunAsync(ConfigModel config)
         {
             return Task.Run(() =>
@@ -94,7 +97,7 @@ private string GenerateOptions(string repositoryPath, string excludePackages)
                 options += " -excludePackages " + excludePackages;
             }
 
-                return options;
+            return options;
         }
 
         private string GetDependencies(string repositoryPath)
@@ -150,5 +153,30 @@ private bool InExcludePaths(string dir)
         {
             return _config.ExcludePaths.Any(p => dir.StartsWith(p));
         }
+
+        private string loadExcludeRegexes(string excludePackages)
+        {
+            StringBuilder excludeStringBuilder = new();
+
+            // Silent on any exception thrown by IO.
+            try
+            {
+                string[] lines = File.ReadAllLines(Constants.ExcludePackagesPath);
+                foreach (string line in lines)
+                {
+                    excludeStringBuilder.Append(line + ":");
+                }
+            }
+            catch 
+            {
+                return excludePackages;
+            }
+
+            if (excludeStringBuilder.Length > 0)
+            {
+                excludePackages += ":" + excludeStringBuilder.ToString();
+            }
+            return excludePackages;
+        }
     }
 }