How to get all the enum values in Java?

In this post, I am going to explain how to get all the enum values in Java.

 

Approach 1: Using EnumSet.allOf method.

‘EnumSet.allOf ‘ method return an enum set containing all of the elements in the specified element type.

Set<AppState> appStates = EnumSet.allOf(AppState.class);

Approach 2: Using Class#getEnumConstants method.

Class#getEnumConstants() method return all the elements of this enum class or null if this Class object does not represent an enum type.

AppState[] appStatesArr = AppState.class.getEnumConstants();
for(AppState appState: appStatesArr) {
	System.out.println(appState);
}

 

Approach 3: Using EnumClass.values() method.

AppState[] appStatesArr = AppState.values();
for(AppState appState: appStatesArr) {
	System.out.println(appState);
}

 

Find the below working application.

 

EnumValuesDemo.java

 

package com.sample.app;

import java.util.EnumSet;
import java.util.Set;

public class EnumValuesDemo {
	private static enum AppState {
		INIT, READY, RUNNING, ABORT;
	}

	public static void main(String[] args) {

		Set<AppState> appStates = EnumSet.allOf(AppState.class);
		System.out.println(appStates + "\n");

		AppState[] appStatesArr = AppState.class.getEnumConstants();
		for (AppState appState : appStatesArr) {
			System.out.println(appState);
		}
		System.out.println();

		appStatesArr = AppState.values();
		for (AppState appState : appStatesArr) {
			System.out.println(appState);
		}
		System.out.println();

	}

}

 

Output

[INIT, READY, RUNNING, ABORT]

INIT
READY
RUNNING
ABORT

INIT
READY
RUNNING
ABORT

 

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