Code:

package com.example;

public class Test {
  enum X {A, B}

  void test(Object obj) {
    switch (obj) {
      case X.A, Integer _ -> System.out.println("A or Integer");
      case String _, X.B -> System.out.println("B or String");
      default -> System.out.println("other");
    }
  }

  public static void main(String[] args) {
    new Test().test("ddd");
  }
}

Compile with --enable-preview

Expected: either successful compilation or two compilation errors in both case lines. Actual: one compilation error:

com\example\Test.java:8:15
java: <identifier> expected

Java parses `case String _, X.B` (when pattern goes first) but does not parse `case X.A, Integer _` when enum constant goes first. It should either accept or reject both. According to current spec draft, it should reject both, but probably it's better to rectify the spec draft.