diff --git a/javascript/extractor/src/com/semmle/jcorn/Parser.java b/javascript/extractor/src/com/semmle/jcorn/Parser.java
index bc98e938dba..5f7383813c6 100644
--- a/javascript/extractor/src/com/semmle/jcorn/Parser.java
+++ b/javascript/extractor/src/com/semmle/jcorn/Parser.java
@@ -3219,7 +3219,7 @@ public class Parser {
     Expression superClass = this.parseClassSuper();
     Position bodyStartLoc = this.startLoc;
     boolean hadConstructor = false;
-    List<MemberDefinition<?>> body = new ArrayList<>();
+    List<MemberDefinition<?>> body = new ArrayList<MemberDefinition<?>>();
     this.expect(TokenType.braceL);
     while (!this.eat(TokenType.braceR)) {
       if (this.eat(TokenType.semi)) continue;
diff --git a/javascript/extractor/src/com/semmle/js/ast/ClassBody.java b/javascript/extractor/src/com/semmle/js/ast/ClassBody.java
index 37a86de8afa..beb23ae3a3e 100644
--- a/javascript/extractor/src/com/semmle/js/ast/ClassBody.java
+++ b/javascript/extractor/src/com/semmle/js/ast/ClassBody.java
@@ -20,7 +20,7 @@ public class ClassBody extends Node {
   }
 
   public MethodDefinition getConstructor() {
-    for (Node md : body) if (md instanceof MethodDefinition && ((MethodDefinition)md).isConstructor()) return (MethodDefinition) md;
+    for (MemberDefinition<?> md : body) if (md.isConstructor()) return (MethodDefinition) md;
     return null;
   }