KT-2499 If Java class is imported, it is visible in completion three times: as Java class, Kotlin class and package

- Add java trace into delegation for lazy resolve session
 #KT-2499 Fixed

idea/src/org/jetbrains/jet/plugin/completion/DescriptorLookupConverter.java

@@ -17,10 +17,13 @@
 package org.jetbrains.jet.plugin.completion;
 
 import com.google.common.collect.Lists;
+import com.intellij.codeInsight.completion.JavaMethodCallElement;
+import com.intellij.codeInsight.completion.JavaPsiClassReferenceElement;
 import com.intellij.codeInsight.lookup.LookupElement;
 import com.intellij.codeInsight.lookup.LookupElementBuilder;
+import com.intellij.codeInsight.lookup.VariableLookupItem;
 import com.intellij.openapi.util.Iconable;
-import com.intellij.psi.PsiElement;
+import com.intellij.psi.*;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.jet.lang.descriptors.*;
@@ -33,6 +36,8 @@ import org.jetbrains.jet.lang.types.lang.KotlinBuiltIns;
 import org.jetbrains.jet.plugin.JetDescriptorIconProvider;
 import org.jetbrains.jet.plugin.completion.handlers.JetClassInsertHandler;
 import org.jetbrains.jet.plugin.completion.handlers.JetFunctionInsertHandler;
+import org.jetbrains.jet.plugin.completion.handlers.JetJavaClassInsertHandler;
+import org.jetbrains.jet.plugin.libraries.DecompiledDataFactory;
 import org.jetbrains.jet.resolve.DescriptorRenderer;
 
 import java.util.List;
@@ -56,6 +61,12 @@ public final class DescriptorLookupConverter {
     @NotNull
     public static LookupElement createLookupElement(@NotNull ResolveSession resolveSession,
             @NotNull DeclarationDescriptor descriptor, @Nullable PsiElement declaration) {
+        if (declaration != null) {
+            LookupElement javaLookupElement = createJavaLookupElementIfPossible(declaration);
+            if (javaLookupElement != null) {
+                return javaLookupElement;
+            }
+        }
 
         LookupElementBuilder element = LookupElementBuilder.create(
                 new JetLookupObject(descriptor, resolveSession, declaration), descriptor.getName().getName());
@@ -113,6 +124,31 @@ public final class DescriptorLookupConverter {
         return element;
     }
 
+    @Nullable
+    private static LookupElement createJavaLookupElementIfPossible(@NotNull PsiElement declaration) {
+        if (declaration instanceof PsiClass) {
+            PsiClass psiClass = (PsiClass) declaration;
+            if (!DecompiledDataFactory.isCompiledFromKotlin(psiClass)) {
+                return new JavaPsiClassReferenceElement(psiClass).setInsertHandler(JetJavaClassInsertHandler.JAVA_CLASS_INSERT_HANDLER);
+            }
+        }
+
+        if (declaration instanceof PsiMember) {
+            PsiClass containingClass = ((PsiMember) declaration).getContainingClass();
+            if (containingClass != null && !DecompiledDataFactory.isCompiledFromKotlin(containingClass)) {
+                if (declaration instanceof PsiMethod) {
+                    return new JavaMethodCallElement((PsiMethod) declaration);
+                }
+
+                if (declaration instanceof PsiField) {
+                    return new VariableLookupItem((PsiField) declaration);
+                }
+            }
+        }
+
+        return null;
+    }
+
     @NotNull
     public static LookupElement createLookupElement(
             @NotNull ResolveSession resolveSession,

idea/src/org/jetbrains/jet/plugin/libraries/DecompiledDataFactory.java

@@ -44,7 +44,7 @@ import java.util.*;
  * @author Evgeny Gerashchenko
  * @since 3/11/12
  */
-class DecompiledDataFactory {
+public class DecompiledDataFactory {
     private static final String JET_CLASS = JetClass.class.getName();
     private static final String JET_METHOD = JetMethod.class.getName();
     private static final String DECOMPILED_COMMENT = "/* compiled code */";
@@ -196,11 +196,11 @@ class DecompiledDataFactory {
         return false;
     }
 
-    static boolean isKotlinClass(PsiClass psiClass) {
+    public static boolean isKotlinClass(@NotNull PsiClass psiClass) {
         return hasAnnotation(psiClass, JET_CLASS);
     }
 
-    static boolean isKotlinNamespaceClass(PsiClass psiClass) {
+    public static boolean isKotlinNamespaceClass(@NotNull PsiClass psiClass) {
         if (JvmAbi.PACKAGE_CLASS.equals(psiClass.getName()) && !isKotlinClass(psiClass)) {
             for (PsiMethod method : psiClass.getMethods()) {
                 if (hasAnnotation(method, JET_METHOD)) {
@@ -210,4 +210,8 @@ class DecompiledDataFactory {
         }
         return false;
     }
+
+    public static boolean isCompiledFromKotlin(@NotNull PsiClass psiClass) {
+        return isKotlinClass(psiClass) || isKotlinNamespaceClass(psiClass);
+    }
 }