Untie JavaTypeSubstitutor.EMPTY from PsiSubstitutor

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/structure/JavaTypeParameter.java

@@ -35,6 +35,9 @@ public interface JavaTypeParameter extends JavaClassifier, JavaNamedElement {
     @Nullable
     JavaTypeParameterListOwner getOwner();
 
+    @NotNull
+    JavaType getType();
+
     @NotNull
     JavaTypeProvider getTypeProvider();
 }

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/structure/JavaTypeParameterImpl.java

@@ -16,10 +16,7 @@
 
 package org.jetbrains.jet.lang.resolve.java.structure;
 
-import com.intellij.psi.PsiClass;
-import com.intellij.psi.PsiMethod;
-import com.intellij.psi.PsiTypeParameter;
-import com.intellij.psi.PsiTypeParameterListOwner;
+import com.intellij.psi.*;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.jet.lang.resolve.name.Name;
@@ -74,6 +71,12 @@ public class JavaTypeParameterImpl extends JavaClassifierImpl implements JavaTyp
         return null;
     }
 
+    @NotNull
+    @Override
+    public JavaType getType() {
+        return JavaTypeImpl.create(JavaPsiFacade.getInstance(getPsi().getProject()).getElementFactory().createType(getPsi()));
+    }
+
     @Override
     @NotNull
     public JavaTypeProvider getTypeProvider() {

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/structure/JavaTypeSubstitutor.java

@@ -16,14 +16,37 @@
 
 package org.jetbrains.jet.lang.resolve.java.structure;
 
-import com.intellij.psi.PsiSubstitutor;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.Collections;
 import java.util.Map;
 
 public interface JavaTypeSubstitutor {
-    JavaTypeSubstitutor EMPTY = new JavaTypeSubstitutorImpl(PsiSubstitutor.EMPTY);
+    JavaTypeSubstitutor EMPTY = new JavaTypeSubstitutor() {
+        @NotNull
+        @Override
+        public JavaType substitute(@NotNull JavaType type) {
+            return type;
+        }
+
+        @Nullable
+        @Override
+        public JavaType substitute(@NotNull JavaTypeParameter typeParameter) {
+            return typeParameter.getType();
+        }
+
+        @NotNull
+        @Override
+        public Map<JavaTypeParameter, JavaType> getSubstitutionMap() {
+            return Collections.emptyMap();
+        }
+
+        @Override
+        public String toString() {
+            return "Empty JavaTypeSubstitutor";
+        }
+    };
 
     @NotNull
     JavaType substitute(@NotNull JavaType type);