Fix ConfigurationBuilder addClassLoaders

src/main/java/org/reflections/util/ConfigurationBuilder.java

@@ -301,9 +301,9 @@ public ConfigurationBuilder addClassLoader(ClassLoader classLoader) {
 
     /** add class loader, might be used for resolving methods/fields */
     public ConfigurationBuilder addClassLoaders(ClassLoader... classLoaders) {
-        this.classLoaders = this.classLoaders == null ? classLoaders :
-                Stream.concat(Stream.concat(Arrays.stream(this.classLoaders), Arrays.stream(classLoaders)), Stream.of(ClassLoader.class))
-                        .distinct().toArray(ClassLoader[]::new);
+        this.classLoaders = this.classLoaders == null
+                            ? classLoaders
+                            : Stream.concat(Arrays.stream(this.classLoaders), Arrays.stream(classLoaders)).toArray(ClassLoader[]::new);
         return this;
     }
 

src/test/java/org/reflections/util/ConfigurationBuilderTest.java

@@ -0,0 +1,22 @@
+package org.reflections.util;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class ConfigurationBuilderTest
+{
+    @Test
+    public void testCallingAddClassLoaderMoreThanOnce()
+    {
+        ClassLoader fooClassLoader = new ClassLoader() { };
+        ClassLoader barClassLoader = new ClassLoader() { };
+
+        ConfigurationBuilder configurationBuilder = new ConfigurationBuilder()
+                .addClassLoader( fooClassLoader  );
+
+        // Attempt to add a second class loader
+        configurationBuilder.addClassLoader( barClassLoader );
+        assertTrue( true );
+    }
+}