Java: Check if enum contains a given string?

Here's my problem - I'm looking for (if it even exists) the enum equivalent of ArrayList.contains();.

Here's a sample of my code problem:

enum choices {a1, a2, b1, b2};

if(choices.???(a1)}{
//do this
} 

Now, I realize that an ArrayList of Strings would be the better route here but I have to run my enum contents through a switch/case elsewhere. Hence my problem.

Assuming something like this doesn't exist, how could I go about doing it?

This should do it:

public static boolean contains(String test) {

    for (Choice c : Choice.values()) {
        if (c.name().equals(test)) {
            return true;
        }
    }

    return false;
}

This way means you do not have to worry about adding additional enum values later, they are all checked.

Edit: If the enum is very large you could stick the values in a HashSet:

public static HashSet<String> getEnums() {

  HashSet<String> values = new HashSet<String>();

  for (Choice c : Choice.values()) {
      values.add(c.name());
  }

  return values;
}

Then you can just do: values.contains("your string") which returns true or false.