Java - What is the output: Enum Constants Reverse Lookup

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Question

What is the output from the following code 

enum Level {
  LOW, MEDIUM, HIGH, URGENT;
}

public class Main {
  public static void main(String... args) {
    Level low1 = Level.valueOf("Low"); // A reverse lookup using a name
    Level low2 = Level.values()[0]; // A reverse lookup using an ordinal
    System.out.println(low1);
    System.out.println(low2);
    System.out.println(low1 == low2);
  }
}


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Exception in thread "main" java.lang.IllegalArgumentException: No enum constant Level.Low
	at java.lang.Enum.valueOf(Enum.java:238)
	at Level.valueOf(Main.java:1)
	at Main.main(Main.java:7)

Note

The reverse lookup for enum constants is case-sensitive.

If you use an invalid constant name with the valueOf() method, an IllegalArgumentException is thrown.