Java enum equals string

This is the common base class of all Java language enumeration types. More information about enums, including descriptions of the implicitly declared methods synthesized by the compiler, can be found in section 8.9 of The Java™ Language Specification . Note that when using an enumeration type as the type of a set or as the type of the keys in a map, specialized and efficient set and map implementations are available.

Constructor Summary

Method Summary

Returns the ordinal of this enumeration constant (its position in its enum declaration, where the initial constant is assigned an ordinal of zero).

Methods declared in class java.lang.Object

Constructor Detail

Enum

Sole constructor. Programmers cannot invoke this constructor. It is for use by code emitted by the compiler in response to enum type declarations.

Method Detail

name

Returns the name of this enum constant, exactly as declared in its enum declaration. Most programmers should use the toString() method in preference to this one, as the toString method may return a more user-friendly name. This method is designed primarily for use in specialized situations where correctness depends on getting the exact name, which will not vary from release to release.

ordinal

Returns the ordinal of this enumeration constant (its position in its enum declaration, where the initial constant is assigned an ordinal of zero). Most programmers will have no use for this method. It is designed for use by sophisticated enum-based data structures, such as EnumSet and EnumMap .

toString

Returns the name of this enum constant, as contained in the declaration. This method may be overridden, though it typically isn’t necessary or desirable. An enum type should override this method when a more «programmer-friendly» string form exists.

equals

hashCode

public final int hashCode()

clone

protected final Object clone() throws CloneNotSupportedException

Throws CloneNotSupportedException. This guarantees that enums are never cloned, which is necessary to preserve their «singleton» status.

compareTo

Compares this enum with the specified object for order. Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object. Enum constants are only comparable to other enum constants of the same enum type. The natural order implemented by this method is the order in which the constants are declared.

getDeclaringClass

Returns the Class object corresponding to this enum constant’s enum type. Two enum constants e1 and e2 are of the same enum type if and only if e1.getDeclaringClass() == e2.getDeclaringClass(). (The value returned by this method may differ from the one returned by the Object.getClass() method for enum constants with constant-specific class bodies.)

valueOf

public static Enum> T valueOf(Class enumType, String name)

Returns the enum constant of the specified enum type with the specified name. The name must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.) Note that for a particular enum type T , the implicitly declared public static T valueOf(String) method on that enum may be used instead of this method to map from a name to the corresponding enum constant. All the constants of an enum type can be obtained by calling the implicit public static T[] values() method of that type.

finalize

protected final void finalize()

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For further API reference and developer documentation see the Java SE Documentation, which contains more detailed, developer-targeted descriptions with conceptual overviews, definitions of terms, workarounds, and working code examples.
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Thursday, March 16, 2023

Comparing Enum to String in Java

Sometimes you may have the scenario where you want to compare String to enum type in Java. For example you may have an enum with product codes and you want to check that the passed produce code is one of the predefined product codes or not.

Here one thing to note is directly comparing enum value with a string won’t work as they both will be of different types.

For example, notice in the code snippet given below where enum type d is directly compared with the String, it won’t give any output as they will never be equal.

enum Day < SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY >public class EnumDemo < public static void main(String[] args) < EnumDemo ed = new EnumDemo(); ed.checkDay("TUESDAY"); >private void checkDay(String str) < Day[] allDays = Day.values(); for(Day d : allDays)< if(d.equals(str))< System.out.println("Day of week- " + d.name()); >> > >

Comparing String to Enum type in Java

toString()— Returns the name of this enum constant, as contained in the declaration.
name()— Returns the name of this enum constant, exactly as declared in its enum declaration.

Using toString() method to compare enum to String in Java

enum Day < SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY >public class EnumDemo < public static void main(String[] args) < EnumDemo ed = new EnumDemo(); ed.checkDay("TUESDAY"); >private void checkDay(String str) < Day[] allDays = Day.values(); for(Day d : allDays)< //Comparing if(d.toString().equals(str))< System.out.println("Day of week- " + d.name()); >> > >

That will work as desired and give you the output — Day of week- TUESDAY

Using name() method to compare enum to String in Java

Enum class also has a name() method that returns the name of this enum constant, exactly as declared in its enum declaration. Though a word of caution here according to Java docs —

«Most programmers should use the toString() method in preference to this one, as the toString method may return a more user-friendly name. This method is designed primarily for use in specialized situations where correctness depends on getting the exact name, which will not vary from release to release.»

enum Day < SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY >public class EnumDemo < public static void main(String[] args) < EnumDemo ed = new EnumDemo(); ed.checkDay("TUESDAY"); >private void checkDay(String str) < Day[] allDays = Day.values(); for(Day d : allDays)< if(d.name().equals(str))< System.out.println("Day of week- " + d.name()); >> > >

Using name() method also gives the desired output — Day of week- TUESDAY

That’s all for this topic Comparing Enum to String in Java. If you have any doubt or any suggestions to make please drop a comment. Thanks!

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How to Compare String to Enum Java

How to Compare String to Enum Java? The Enum is a keyword used while defining enumeration which contains constant values which are accessible. Enum expands as enumeration. The string is a collection of a sequence of characters that are represented between double quotes (“ ”). Now in this blog, we are comparing the string to an enum.

Program to Compare String to Enum Java

Here we are comparing the enum of days to the string, this is obviously not equal hence the result will be not equal. The enum is a different type and the string is different while comparing it is not equal. Check the below program.

enum Day < SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY >public class Main < public static void main(String[] args) < Main obj = new Main(); obj.checkEnum("TUESDAY"); >private void checkEnum(String string) < Day[] Days = Day.values(); for (Day day : Days) < System.out.println("Day: " + day.name()); if (day.equals(string)) < System.out.println("Equal"); >else < System.out.println("Not equal"); >> > >

Day: SUNDAY
Not equal
Day: MONDAY
Not equal
Day: TUESDAY
Not equal
Day: WEDNESDAY
Not equal
Day: THURSDAY
Not equal
Day: FRIDAY
Not equal
Day: SATURDAY
Not equal

How To Compare Enum With String In Java

As we saw in the above program the string and enum cannot be compared directly even if it looks the same as the types are different which might result in inequality, so to overcome this we need to first convert the enum value to string and then compare to do this here we are using toString() method.

enum Day < SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY >public class Main < public static void main(String[] args) < Main obj = new Main(); obj.checkEnum("TUESDAY"); >private void checkEnum(String string) < Day[] Days = Day.values(); for (Day day : Days) < System.out.println("Day: " + day.name()); if (day.toString().equals(string)) < System.out.println("Equal"); break; >else < System.out.println("Not equal"); >> > >

Day: SUNDAY
Not equal
Day: MONDAY
Not equal
Day: TUESDAY
Equal

Now let us see the same thing with the name() method. The name() method yields the same output as the toString() method but the difference is the name() method returns the enum constant that is exactly as same as the one in the declaration. The toString() method returns which are contained in the declaration.

enum Day < SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY >public class Main < public static void main(String[] args) < Main obj = new Main(); obj.checkEnum("TUESDAY"); >private void checkEnum(String string) < Day[] Days = Day.values(); for (Day day : Days) < System.out.println("Day: " + day.name()); if (day.name().equals(string)) < System.out.println("Equal"); break; >else < System.out.println("Not equal"); >> > >

Day: SUNDAY
Not equal
Day: MONDAY
Not equal
Day: TUESDAY
Equal

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