![]() Next, let’s extend the example above by implementing the transition from one stage of a pizza order to another. We can define constructors, methods, and fields inside enum types, which makes them very powerful. The compiler will flag the comparison as an incompatibility error: We avoid this issue by using the “=” operator. ![]() This is because the values of the enum and the getStatus method coincidentally are the same however, logically the comparison should be false. If(testPz.getStatus() = ) Īs for compile-time safety, let’s look at an example where we’ll determine that an enum of a different type is equal by comparing it using the equals method. Conversely, if we use the equals method, we will get a NullPointerException: if(testPz.getStatus().equals()) This approach takes the name of the enum consistent as a string and returns the corresponding enum regular if discovered. Either value can be null and we won’t get a NullPointerException. The maximum direct manner to convert a string to an enum is with the aid of the usage of the valueOf () technique furnished by means of the enum itself. Furthermore, the “=” operator provides compile-time and run-time safety.įirst, we’ll look at run-time safety in the following snippet, where we’ll use the “=” operator to compare statuses. Methods declared in interface enum types ensure that only one instance of the constants exist in the JVM, we can safely use the “=” operator to compare two variables, like we did in the above example. Performs the given action for each element of the Iterable until all elements have been processed or the action throws an exception. Returns an array containing all of the elements in this collection, using the provided generator function to allocate the returned array. Returns a sequential Stream with this collection as its source. Removes all of the elements of this collection that satisfy the given predicate. Returns a possibly parallel Stream with this collection as its source. Removes from this set all of its elements that are contained in the specified collection (optional operation). Returns the hash code value for this set. statement.executeUpdate() All we need is to pass the Java enum value as a String, and the driver will send it to PostgreSQL in. Some other methods of classes or interfaces are defined below that somehow helps us to get a better understanding of AbstractSet Class as follows: Methods declared in class Ĭompares the specified object with this set for equality. The computations are executed in constant time and the space required is very little.Ĭreates an enum set containing all of the elements in the specified element type.Ĭreates an enum set with the same element type as the specified enum set, initially containing all the elements of this type that are not contained in the specified set.Ĭreates an enum set initialized from the specified collection.Ĭreates an enum set with the same element type as the specified enum set, initially containing the same elements (if any).Ĭreates an empty enum set with the specified element type.Ĭreates an enum set initially containing the specified element.Ĭreates an enum set initially containing the specified elements.Ĭreates an enum set initially containing all of the elements in the range defined by the two specified endpoints.EnumSet is faster than HashSet because we no need to compute any hashCode to find the right bucket.Due to its implementation using RegularEnumSet and JumboEnumSet, all the methods in an EnumSet are implemented using bitwise arithmetic operations. ![]()
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