Optimize within matching

ByteBuddy's StringMatcher uses String.matches which performs about 10x slower
than caching a Pattern inside a custom PatternMatcher

Uglify the test / reference pattern examples to more closely match the required patterns

Flag incorrect InstrumentationLoader test

README.md

@@ -6,5 +6,5 @@
 **Kanela** is a Java Agent written in Java 8+ and powered by [ByteBuddy] with some additionally [ASM] features to provide a simple way to instrument applications running on the JVM and allow introduce Kamon features such as context propagation and metrics.
 
 
-[ByteBuddy]:http://bytebuddy.net/#/
-[ASM]:http://asm.ow2.org/
+[ByteBuddy]:https://bytebuddy.net/#/
+[ASM]:https://asm.ow2.io/

agent-test/src/main/resources/application.conf

@@ -1,14 +1,14 @@
 kanela {
-    modules {
-      example-module {
-        name = "Example Module"
-        stoppable = false
-        instrumentations = [
-          "app.kanela.instrumentation.MonitorInstrumentation",
-        ]
-        within = [ "app.kanela.cases.+" ]
-      }
+  modules {
+    example-module {
+      name = "Example Module"
+      stoppable = false
+      instrumentations = [
+        "app.kanela.instrumentation.MonitorInstrumentation",
+      ]
+      within = [ "app\\.kanela\\.cases\\..+" ]
     }
-    debug-mode = false
-    class-dumper.enabled = false
-}
+  }
+  debug-mode = false
+  class-dumper.enabled = false
+}

agent-test/src/test/resources/application.conf

@@ -10,8 +10,8 @@ kanela {
       instrumentations = [ ] // written by spec
 
       within = [
-        "app.kanela..*",
-        "java.net.*"
+        "app\\.kanela\\..*",
+        "java\\.net\\..*",
       ]
 
       bootstrap-injection {

agent/src/main/java/kanela/agent/builder/KanelaAgentBuilder.java

@@ -24,6 +24,7 @@
 import kanela.agent.cache.PoolStrategyCache;
 import kanela.agent.resubmitter.PeriodicResubmitter;
 import kanela.agent.util.ListBuilder;
+import kanela.agent.util.PatternMatcher;
 import kanela.agent.util.conf.KanelaConfiguration;
 import kanela.agent.util.log.Logger;
 import lombok.Value;
@@ -36,6 +37,7 @@
 import net.bytebuddy.dynamic.scaffold.MethodGraph;
 import net.bytebuddy.dynamic.scaffold.TypeValidation;
 import net.bytebuddy.matcher.ElementMatcher;
+import net.bytebuddy.matcher.NameMatcher;
 
 import java.lang.instrument.Instrumentation;
 import java.util.ArrayList;
@@ -141,10 +143,20 @@ private AgentBuilder.Listener additionalListeners() {
     }
 
     private ElementMatcher.Junction<NamedElement> ignoreMatches() {
-        return not(nameMatches(moduleDescription.getWithinPackage()));
+        final String withinPackage = moduleDescription.getWithinPackage();
+        if (withinPackage.isEmpty()) {
+            return any();
+        } else {
+            return not(new NameMatcher<>(new PatternMatcher(withinPackage)));
+        }
     }
 
     private ElementMatcher.Junction<NamedElement> moduleExcludes() {
-        return nameMatches(moduleDescription.getExcludePackage());
+        final String moduleExcludes = moduleDescription.getExcludePackage();
+        if (moduleExcludes.isEmpty()) {
+            return none();
+        } else {
+            return new NameMatcher<>(new PatternMatcher(moduleExcludes));
+        }
     }
 }

agent/src/main/java/kanela/agent/util/PatternMatcher.java

@@ -0,0 +1,18 @@
+package kanela.agent.util;
+
+import net.bytebuddy.matcher.ElementMatcher;
+
+import java.util.regex.Pattern;
+
+public class PatternMatcher extends ElementMatcher.Junction.AbstractBase<String> {
+    private final Pattern regex;
+
+    public PatternMatcher(final String regex) {
+        this.regex = Pattern.compile(regex);
+    }
+
+    @Override
+    public boolean matches(final String target) {
+        return regex.matcher(target).matches();
+    }
+}

agent/src/main/resources/reference.conf

@@ -40,9 +40,9 @@ kanela {
     #     disable-class-format-changes = "true|false" (optional)
     #     # List of fully qualified name of the implementation of kanela.agent.api.instrumentation.InstrumentationBuilderr.
     #     instrumentations = []
-    #     # Excludes all types that matches the list of patterns. e.g. org.apache. *
+    #     # Excludes all types that match the list of patterns. e.g. org\.apache\..*
     #     exclude = []
-    #     # Only instruments types that are within the list of patterns. e.g. javax.*
+    #     # Only instruments types that are within the list of patterns. e.g. javax\..*
     #     within = []
     #     # The exception handler strategy on instrumentation error: LOG|SUPPRESS
     #     exception-handler-strategy = "SUPPRESS"

agent/src/test/scala/kanela/agent/InstrumentationLoaderSpec.scala

@@ -41,13 +41,17 @@ class InstrumentationLoaderSpec extends FlatSpec with Matchers with BeforeAndAft
 
     when(agentModuleDescriptionMock.getInstrumentations).thenReturn(JList.empty[String]())
     when(agentModuleDescriptionMock.getWithinPackage).thenReturn("")
+    when(agentModuleDescriptionMock.getExcludePackage).thenReturn("")
     when(agentModuleDescriptionMock.getName).thenReturn("x-module")
 
     InstrumentationLoader.load(instrumentationMock, Thread.currentThread().getContextClassLoader, agentConfiguration)
 
     verify(agentConfiguration, times(1)).getAgentModules
   }
 
+  // TODO FIXME: This test is useless since it explodes before getting to InstrumentationLoader.load
+  // It should be refactored to expect a specific exception and not a generic RuntimeException
+  // (currently blowing up due to errorneous spy+mock combo)
   "with an unknown instrumentation" should "blow up" in {
     val instrumentationMock = mock(classOf[Instrumentation])
     val agentModuleDescriptionMock = mock(classOf[ModuleConfiguration])
@@ -81,6 +85,7 @@ class InstrumentationLoaderSpec extends FlatSpec with Matchers with BeforeAndAft
 
     when(agentModuleDescriptionMock.getInstrumentations).thenReturn(JList.of[String]("kanela.agent.instrumentation.KamonFakeInstrumentationBuilder"))
     when(agentModuleDescriptionMock.getWithinPackage).thenReturn("")
+    when(agentModuleDescriptionMock.getExcludePackage).thenReturn("")
     when(agentModuleDescriptionMock.getName).thenReturn("x-module")
 
     InstrumentationLoader.load(instrumentationMock, Thread.currentThread().getContextClassLoader, agentConfiguration)