make type parameter implements interface: don't insert any methods in code

java/java-psi-impl/src/com/intellij/codeInsight/generation/OverrideImplementExploreUtil.java

@@ -44,7 +44,7 @@ public class OverrideImplementExploreUtil {
     Map<MethodSignature, PsiMethod> finals = new LinkedHashMap<>();
     Map<MethodSignature, PsiMethod> concretes = new LinkedHashMap<>();
 
-    if (aClass.isAnnotationType()) return Collections.emptyMap();
+    if (aClass.isAnnotationType() || aClass instanceof PsiTypeParameter) return Collections.emptyMap();
 
     PsiUtilCore.ensureValid(aClass);
     Collection<HierarchicalMethodSignature> allMethodSigs = aClass.getVisibleSignatures();

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/changeParameterClass/afterTypeParameterBound.java

@@ -0,0 +1,10 @@
+// "Make 'T' implement 'b'" "true"
+class a<T extends b<String>> {
+    void f(b<String> r, T t) {
+        r.g(t);
+    }
+}
+interface b<T> {
+  void g(b<T> t);
+}
+

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/changeParameterClass/beforeTypeParameterBound.java

@@ -0,0 +1,10 @@
+// "Make 'T' implement 'b'" "true"
+class a<T> {
+    void f(b<String> r, T t) {
+        r.g(<caret>t);
+    }
+}
+interface b<T> {
+  void g(b<T> t);
+}
+