diff --git a/plugins/gradle/java/src/service/resolve/GradleExtensionsContributor.kt b/plugins/gradle/java/src/service/resolve/GradleExtensionsContributor.kt
index 6b5ed6e69323..302cb6eccdba 100644
--- a/plugins/gradle/java/src/service/resolve/GradleExtensionsContributor.kt
+++ b/plugins/gradle/java/src/service/resolve/GradleExtensionsContributor.kt
@@ -102,7 +102,7 @@ class GradleExtensionsContributor : GradleMethodContextContributor {
           containingClass = taskContainerClass
           returnType = returnClass
         }
-        methodBuilder.addParameter("task", GRADLE_API_TASK, true)
+        methodBuilder.addOptionalParameter("task", GRADLE_API_TASK)
         place.putUserData(RESOLVED_CODE, true)
         if (!processor.execute(methodBuilder, state)) return false
       }
@@ -138,7 +138,7 @@ class GradleExtensionsContributor : GradleMethodContextContributor {
             containingClass = projectClass
             returnType = returnClass
             if (parent is GrMethodCallExpressionImpl && parent.argumentList.namedArguments.isNotEmpty()) {
-              addParameter("args", JAVA_UTIL_MAP, true)
+              addOptionalParameter("args", JAVA_UTIL_MAP)
             }
             val closureParam = addAndGetParameter("configuration", GROOVY_LANG_CLOSURE, true)
             closureParam.putUserData(DELEGATES_TO_KEY, gradleTask.typeFqn)
@@ -201,7 +201,7 @@ class GradleExtensionsContributor : GradleMethodContextContributor {
             val returnClass = groovyPsiManager.createTypeByFQClassName(GROOVY_LANG_CLOSURE, resolveScope) ?: return true
             val methodBuilder = GrLightMethodBuilder(place.manager, name).apply {
               returnType = returnClass
-              addParameter("args", JAVA_LANG_OBJECT, true)
+              addOptionalParameter("args", JAVA_LANG_OBJECT)
             }
             return processor.execute(methodBuilder, state)
           }
@@ -302,7 +302,7 @@ fun processExtension(processor: PsiScopeProcessor,
       returnType = returnClass
     }
     if (shouldProcessMethods) {
-      methodBuilder.addParameter("configuration", GROOVY_LANG_CLOSURE, true)
+      methodBuilder.addOptionalParameter("configuration", GROOVY_LANG_CLOSURE)
     }
     place.putUserData(RESOLVED_CODE, true)
     if (!processor.execute(methodBuilder, state)) return false
diff --git a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/builder/XmlMarkupBuilderNonCodeMemberContributor.java b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/builder/XmlMarkupBuilderNonCodeMemberContributor.java
index 5f3309504f12..397e68ab93a5 100644
--- a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/builder/XmlMarkupBuilderNonCodeMemberContributor.java
+++ b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/builder/XmlMarkupBuilderNonCodeMemberContributor.java
@@ -59,7 +59,7 @@ public class XmlMarkupBuilderNonCodeMemberContributor extends BuilderMethodsCont
     // (Map, Object, Closure)
     res = createMethod(name, clazz, place);
     res.addParameter("attributes", JAVA_UTIL_MAP);
-    res.addParameter("value", JAVA_LANG_OBJECT, true);
+    res.addOptionalParameter("value", JAVA_LANG_OBJECT);
     res.addAndGetParameter("body", GROOVY_LANG_CLOSURE, true).putUserData(DELEGATES_TO_KEY, FQN);
     for (GrReflectedMethod method : res.getReflectedMethods()) {
       if (!processor.process(method)) return false;
@@ -70,7 +70,7 @@ public class XmlMarkupBuilderNonCodeMemberContributor extends BuilderMethodsCont
     // (Object, Map, Closure)
     res = createMethod(name, clazz, place);
     res.addParameter("value", JAVA_LANG_OBJECT);
-    res.addParameter("attributes", JAVA_UTIL_MAP, true);
+    res.addOptionalParameter("attributes", JAVA_UTIL_MAP);
     res.addAndGetParameter("body", GROOVY_LANG_CLOSURE, true).putUserData(DELEGATES_TO_KEY, FQN);
     for (GrReflectedMethod method : res.getReflectedMethods()) {
       if (!processor.process(method)) return false;
diff --git a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/GrLightMethodBuilder.java b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/GrLightMethodBuilder.java
index 5fec3dce6a0a..ad134bee64f3 100644
--- a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/GrLightMethodBuilder.java
+++ b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/GrLightMethodBuilder.java
@@ -249,7 +249,12 @@ public class GrLightMethodBuilder extends LightElement implements GrMethod, Orig
   }
 
   @NotNull
-  public GrLightMethodBuilder addParameter(@NotNull String name, @NotNull String type, boolean isOptional) {
+  public GrLightMethodBuilder addOptionalParameter(@NotNull String name, @NotNull String type) {
+    return addParameter(name, type, true);
+  }
+
+  @NotNull
+  private GrLightMethodBuilder addParameter(@NotNull String name, @NotNull String type, boolean isOptional) {
     return addParameter(name, JavaPsiFacade.getElementFactory(getProject()).createTypeFromText(type, this), isOptional);
   }
 
diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/ext/logback/LogbackDelegateMemberContributor.kt b/plugins/groovy/src/org/jetbrains/plugins/groovy/ext/logback/LogbackDelegateMemberContributor.kt
index 58988ebbf12e..d0d33902a739 100644
--- a/plugins/groovy/src/org/jetbrains/plugins/groovy/ext/logback/LogbackDelegateMemberContributor.kt
+++ b/plugins/groovy/src/org/jetbrains/plugins/groovy/ext/logback/LogbackDelegateMemberContributor.kt
@@ -98,7 +98,7 @@ class LogbackDelegateMemberContributor : NonCodeMembersContributor() {
       wrappedBase.copy().apply {
         addParameter("name", JAVA_LANG_STRING)
         addParameter("clazz", classType)
-        addParameter("configuration", GROOVY_LANG_CLOSURE, true)
+        addOptionalParameter("configuration", GROOVY_LANG_CLOSURE)
       }.let {
         if (!delegate.execute(it, state)) return false
       }