diff --git a/org.eclipse.jdt.core.javac/src/org/eclipse/jdt/internal/javac/dom/JavacTypeBinding.java b/org.eclipse.jdt.core.javac/src/org/eclipse/jdt/internal/javac/dom/JavacTypeBinding.java
index f73211dfd33..c1187b0e607 100644
--- a/org.eclipse.jdt.core.javac/src/org/eclipse/jdt/internal/javac/dom/JavacTypeBinding.java
+++ b/org.eclipse.jdt.core.javac/src/org/eclipse/jdt/internal/javac/dom/JavacTypeBinding.java
@@ -173,7 +173,7 @@ static void getKey(StringBuilder builder, Type typeToBuild, boolean isLeaf) {
 					builder.append('L');
 				}
 			}
-			builder.append(typeToBuild.asElement().getQualifiedName().toString().replace('.', '/'));
+			builder.append(typeToBuild.asElement().flatName().toString().replace('.', '/'));
 			if (typeToBuild.isParameterized()) {
 				builder.append('<');
 				for (var typeArgument : typeToBuild.getTypeArguments()) {