Mostly based on:
https://mail.openjdk.java.net/pipermail/compiler-dev/2021-June/017343.html

The following should not compile:
---
void testInt(Integer i) {
  switch (i) {
    case Integer o && o != null, 1: //cannot combine type patterns and constants
      System.out.println("s1");
    default:
      System.out.println("def");
  }
}
---

---
void testInt(Integer i) {
  switch (i) {
    case null, Integer o && o != null: //must be a type pattern
      System.out.println("s1");
    default:
      System.out.println("def");
  }
}
---

---
    switch(selExpr) {
        case String s, null, default : //illegal combination of (type) pattern and default
    }
---