Can you discuss what Enum is and provide an example?

"An Enum is a special data type that allows a variable to be a set of predefined constants. The variable must be equal to at least one of the values that have been predefined for it. Common examples include colors, days of the week, and compass points."

It is typical for interviewers to ask several different questions about the same topic. This is especially true with general questions. General questions are used to set the tone for the interview and confirm your qualifications for the job. After a series of general questions, the interviewer will become comfortable with your credentials and begin to ask more difficult and challenging technical and operational questions.

Job candidates who've done a great deal of preparation for the interview may become impatient with the interviewer if they continue to ask general, non-specific questions. This is a big mistake and could jeopardize your chances of getting the job. Every interviewer is different, and it is your responsibility to adjust your style to theirs. Focus on the questions they are asking and provide them with the answers they expect. This will encourage them to move on to more specific technical questions you have prepared for.

What are some of the advantages of using Enum when coding in Java?

"There are several benefits to incorporating Enum into your Java coding. Some of these are that Enum improves safety, can be placed in or out of a class, and enables you to easily switch cases. Enum can also have variables, constructors, and methods. You need to keep in mind that Enum cannot extend any class and that you cannot make an object of Enum."

This question may seem similar to another one you asked earlier in the interview. Interviewers will often ask the same question in different ways and at different times during the interview. The reason for this is to correlate your answers and ensure that you're being consistent and truthful throughout the interview.

You should always answer any interviewer's question truthfully and honestly. This is especially true if you recognize the question as similar to one you were asked earlier in the interview. Doing this will ensure that you are perceived as consistent and your answers genuine. Keeping your answers brief and to the point will help you to accomplish this as well.

What are some advantages of using Enum over Enum int pattern and Enum string pattern?

"Since I have coded using JDK 1.3 and 1.4, I am familiar with Enum string pattern and int pattern, which used public static final constants to represent a collection of well-known constants of things like 'MonthOfYear.' There were several problems with this approach, such as not having a dedicated Enum type string variable, which represented months of the year. This allowed it to take any arbitrary value. The Enum int pattern can take any arbitrary value, and the compiler won't prevent this. When using Enum, you get both type-safety and compiler checking."

Since only experienced Java programmers will understand this question, the interviewer uses it to confirm your experience level, as noted in your resume. Interviewers ask these questions because it is common for candidates to exaggerate their resumes. It is highly likely that the interviewer has already researched your background in great detail using sources such as LinkedIn and other social media sites. This is why it is very difficult to exaggerate or enhance your qualifications.

If you have the experience necessary to respond to this question accurately, proceed. If not, communicate this to the interviewer. Your answer should always demonstrate your actual qualifications for this job. Interviewers understand that you may not have all the qualifications and are often willing to hire you with the expectation that they will provide additional training to bring you up to the level needed to perform this work. It is very typical for companies to hire junior-level programmers who they can train to use specific methodologies, processes, and procedures preferred by the company.

Can you talk about the advantages of using Enum as Singleton?

"Enum provides a quick shortcut to implement the Singleton design pattern. Enum Singleton is a promising technology since it can handle many programming tasks. These include creating a controlled instance, providing safe serialization safety, and creating thread-safe Singleton. It also eliminates the need to be concerned about double-checking locking and volatile variables."

When an interviewer asks you about the advantages and disadvantages of the technology, they seek your opinion rather than a fact. One rationale behind this type of question is to see if your perspective on the technology matches their organization's. Alternatively, they may be interested in learning new information which may help their company.

You should never try to guess the rationale behind an interviewer's question. Once you're sure you understand the question and the information the interviewer is looking for, you should answer as straightforwardly and truthfully as possible. While the interviewer is trying to determine if you are the best candidate for this position, you are trying to understand if this job is right for you. If your answers uncover a difference of opinion, it may indicate that there's a potential for conflict after you are hired.

What are some of the benefits of using Enums in Java?

"There are many benefits to incorporating Enum into Java coding. These include the fact that Enum provides type-safe, which means that an Enum variable can be assigned only with predefined constants. If this is not the case, it will issue a compilation error. Other benefits include that Enum can be used in switch-case Java control statements, has its own namespace, and constants can hold values specified at the creation time. You can use Enum to create a Singleton pattern, which is also thread-safe, and passing Enum as an argument to the static factory method makes the method type-safe."

An interviewer will ask you this question if the organization is considering using Enums for their Java programming or if they have already begun using it and want to test your knowledge of the technology. Organizations prefer to hire people who are already familiar with their current processes and procedures or who may be able to innovate and introduce new ideas and technologies. The interviewer is trying to determine where you lie on the spectrum.

When preparing for an interview, you should carefully research the organization to learn as much as you can about its processes and procedures. The more you know about these, the better prepared you will be to answer the interviewer's questions. You can either acknowledge your ability to fit into the organization or stress how you can bring innovations and new technologies to their operations.

Why would a Java programmer incorporate the concept of Enum into their code?

"The reason I incorporate Enum into my code when programming in Java is that Enum is the list of constants. Therefore, it is useful when defining a list of constants. Enum is also useful when the list of outcomes is limited."

Interviewers ask this question knowing that there is no right or wrong answer. They're interested in your opinion about the Enum and why you have decided to apply for this role. These types of questions help the interviewer get to know you a little bit before they proceed to the more technical and challenging questions. It also provides them with an example of your communication style.

Since there are no right or wrong answers to this question, the only requirement is that your answer is genuine, well thought out, and defensible. As long as you can justify your answer and provide some background, you are answering correctly. You may also want to take a few seconds to organize your thoughts before beginning to answer the interviewer's question since they are judging your communication style. Hesitating, using pauses such as 'uh' and 'um,' and other bad communication techniques may jeopardize your success during the interview.

What is the process for iterating over all instances of an Enum?

"Java.lang.Enum includes a values() method that returns an array of all Enum constants. Since every Enum type implicitly extends Java.lang.Enum, they get these values() method. Using this enables you to iterate over all Enum constants of a certain type."

This is an example of an operational question. Interviewers will ask operational questions to determine how you do this job. They're interested in whether your processes match those of their organization. They may also be interested in learning whether you can bring innovative new ideas into the company that will improve their operations and make them more efficient.

Before an interview, you should try to learn as much as you can about the organization's processes and procedures in the job you're interviewing for. This will prepare you for the questions you will be asked during the interview. It will also allow you to align your answers with the company's operations. Alternatively, you may elect to respond to the interviewer's questions with new, innovative ways to get the job done. This will indicate that you can help the organization be more efficient and save money.

Walk me through how you would convert a string to Enum in Java?

"The best way to convert string to Enum in Java is to declare a factory method inside Enum, which should take a string argument and return an Enum. You can even elect to ignore the case. This is the most straightforward methodology for executing this conversion."

When the interviewer asks you to walk them through a process, you can immediately identify the question as being operational. The interviewer wants to know how you go about doing this job. They are interested in seeing if your processes align with those of their organization or if you can bring something new to the group.

Since you have experience in this area, the question should be easy to answer. Simply describe the process you used when performing this operation. Your answer will either be interpreted as being the same process as the one the organization's team currently uses or something new they may want to try out.

Are Enum constants considered to be static and final?

"Enum constants are public static and final. The constants can be accessed directly by invoking the Enum name."

As the interview progresses, the interviewer will continue to ask about specific properties of Enums when used while coding in Java. This is especially true if the interviewer is either the hiring manager or another individual working on the programming team. If you're interviewing with multiple individuals, you may be asked the same question by each interviewer.

Since it is common for multiple interviewers to compare their notes after they have met with you, you want to ensure that you give the same answer to the same question to each interviewer. Once they confirm this, their conversation will turn to your overall qualifications and fit within the organization. If you provide inconsistent answers to different interviewers, it will be a red flag, and your qualifications will be questioned.

What is the default value for Enum's serialVersionUID?

"The serialVersionUID value for all Enums is 0L. This is the default value."

You may recognize this question as a follow-up to one you were previously asked during the interview. Interviewers use follow-up questions to explore the topic in more detail and ascertain the depth of your knowledge of the topic they are questioning you about. This is a common interview technique that you will encounter regardless of the role or the organization with whom you are interviewing.

Responding to follow-up questions is similar to responding to the original question. Keep your answer brief and to the point, without elaborating or embellishing. The interviewer will either ask another follow-up question or move on to a different topic.

Is Enum serializable in Java?

"When coding in Java, Enums are automatically serializable. Therefore, there is no need to add an "implements serializable" clause following an Enum declaration."

When applying for a job, you're likely to be interviewed by a wide range of different people within the organization. These include human resource specialists, hiring managers, other department heads, and possibly even your future peers. Each of these constituents will ask a different set of questions based on their background, knowledge, and role within the organization. After the interview, the interviewers will convene and discuss your qualifications based on their questions and your response.

Since you'll be interviewed by different people with different roles and knowledge, you need to be prepared to answer a broad range of questions. These may range from general questions about why you're interested in the job and the organization to very specific technical questions such as this one. Practicing questions like these and others that explore general topics or behavioral issues is a good way to prepare for the interview. Not only will this put the answers at the top of your mind, but it also allows you to practice the language you use, terminology, and even how you structure your answers.

Is it possible for an Enum constructor to be declared public in Java?

"An Enum constructor cannot be declared as public in Java. The constructor for an Enum type must be designated package-private or private access. The constructor creates the constants that are defined at the beginning of the Enum body. This is why you cannot invoke an Enum constructor."

Interviewers will ask you about possible uses of different technologies during an interview for this type of role. The motivation behind this type of question is to explore how creative you are and whether you will be able to bring innovative skills to the position. While the technology is not normally used for a specific purpose, it may be possible to apply it to the situation the interviewer is asking you about. The interviewer expects you to respond by stating that while it is possible, it may not be common.

If the technology can be used per the interviewer's question, respond affirmatively and describe a situation that illustrates this. If the use described by the interviewer is an outlier, state this in your answer and be prepared for a follow-up question about why it is possible but not practical. This may lead to a dialogue between you and the interviewer about the technology, which could be an opportunity for you to demonstrate your full knowledge of the topic.

Are Enums considered to be a reference type in Java?

"Yes, Enums are considered to be a reference type in Java. Enums are another type of Java class and interface. Enum can have constructors, methods, and variables. Each Enum constant will have its own fields and methods."

By asking this question, the interviewer assumes that you have in-depth knowledge about both Enums and Java. While Enums are not exclusive to Java, you are expected to have this knowledge and be able to provide it to the interviewer. Interviewers are likely to ask you about topics outside of the immediate purview of this job description. They do this to explore how broad your knowledge is and whether you may be able to contribute to operations not related to Java programming.

Since you don't know what questions you'll be asked during the interview, it is best to prepare by refreshing your knowledge about a broad range of topics. Even though you are applying for a java programmer's job in which Enum will be employed, you should still brush up your knowledge about other programming languages such as Perl, R, and C++. It would be best if you could leave the impression that your skills and experience are not limited to this one job description.

Can you create an Enum without constants?

"You can create an Enum without constants. If you choose to do this and the Enum body has other members such as method or constructor, then the first line must contain a semicolon."

Throughout the interview, the interviewer will ask you questions about the capabilities and limitations of different technologies you will be using in this role. Knowing these will enhance your opportunity to be hired by the organization. Not only is the interviewer expecting you to provide a yes or no answer to these types of questions, but they are also looking for an example or description of how the technology is employed.

When responding to this question, you should first answer in either the affirmative or negative, which is a direct response to a question. Then you should expand on your answer to provide a rationale or an example of how the technology is used. A simple one or two-line answer will suffice. The interviewer will ask you a follow-up question if they need more information or want to explore the topic in more detail.

Can you describe an Enum ordinal in Java?

"When using Enum ordinal in Java, it will return the ordinal of the Enum constant, in its original position defined in the Enum declaration. This assumes the initial constant is assigned an ordinal of zero. This is a rarely used method. It is typically used by complex Enum-based data structures, including EnumMap, EnumSet, and compareTo methods."

This is an example of a qualitative question. The interviewer is asking you to describe a concept used in this job. The purpose of this question is to determine your knowledge of the topic and to see how well you communicate.

It is okay to expound on the topic in more detail when answering qualitative questions. Keep in mind that the interviewer is also evaluating your communication style. This is important for any job since you are expected to collaborate with other members of the organization who may not have the technical expertise you do. Being able to describe complex technical topics in a simple, easy to understand language is an important skill Java programmers who use Enum must possess.

Is it possible for Enum to have a main method in Java?

"Yes, it is possible for Enum to have a startup main method that JVM executes."

Interviewers can ask you both quantitative and qualitative questions. Quantitative questions have a definite answer. Qualitative questions are more liberal and may have a range of answers, all of which are correct. Quantitative questions demonstrate your ability to reason, while qualitative questions demonstrate your creativeness as well as your communication style.

When answering a quantitative question, keep your answer direct and to the point, providing the answer and possibly a brief rationale for it. When responding to a qualitative question, you can elaborate your answer a little bit more, creating a narrative of the answer and the reason you selected it. As with any question, be prepared for follow-ups that indicate the topic is important to the organization or that the interviewer needs more information.

Can you define the term 'Enumeration' and discuss what it is used for when creating code in Java?

"An Enumeration is an interface that contains techniques for retrieving the underlying data structure from which the Enumeration is obtained. It allows sequential access to all the elements stored in the associated collection."

This is a question the interviewer will ask early in the interview for a java developer's job in which the Enum is used. Interviewers use these questions to begin the conversation, learn more about your background, and collect information they can use later in the interview. This is known as an opening question.

When answering general questions like this, make sure you address the interviewer's question in full, providing all the information they are requesting. Keep your answer brief and to the point, and don't embellish. The interviewer will always ask a follow-up question if they need additional information.

Can an object be created of Enum?

"No, you can not create an object of Enum."

Since this is a very basic and easy to answer question, the interviewer will likely ask it early in the interview. Interviewers prefer to start with easy to answer questions because it helps you relax and gain confidence. Their job is to get to know the real you, and they can't do this if you're tense and nervous during the interview. Good interviewers will work to make you as relaxed as possible so they can clearly understand your qualifications for the job.

When asked any easy-to-answer question, try not to be smug or dismiss the question as a throwaway. You can never be fully aware of why the interviewer is asking this question or what they're trying to learn about you when they ask it. Always strive to communicate clearly, answer the question completely, and prepare for a follow-up question.

Is it possible to extend an Enum to add elements?

"No, it is not possible to extend Enum further in the code. It is defined only with the keyword Enum and filled with elements. However, these same elements cannot be added later in the program using some other method."

It is not unusual for interviewers to mix both long, complex questions with simple ones that demand a yes or no answer. The simpler questions are used as bridges between the more complex ones. This provides you an opportunity to relax and rest a little bit and helps the interviewer create pauses in the process, which they use to organize the next questions they will ask.

Just because the question is simple and demands only a yes or no answer, you should still give it all the attention you would for a more complex and challenging question. Often, candidates become complacent during an interview and will only expend as much effort as necessary when answering an interviewer's question. Interviewers are trained to perceive this. If you're complacent in the interview, it may indicate that you will become complacent if hired for the job.

Is it possible to declare Enum constants as static and final?

"Yes, you can use the constructor with the name of Enum. You first specify the Enum, then define the constants. You can then invoke the constructor when needed."

Interviewers can ask both definite and indefinite questions. A definite question has a single right answer and may be a yes-or-no-question. Indefinite questions may have several different answer options, all of which are correct. The reason interviewers use these types of questions is that they provide examples of your approach to problem-solving. Your answers to definite questions will indicate that you are decisive. Your answers to indefinite questions will indicate your flexibility and adaptability.

When answering a definite question that is normally looking for a yes or no response, quickly choose your response and provide it to the interviewer. This will demonstrate your decisiveness. If you're unsure about your response, ask a clarifying question to narrow down the rationale behind why the interview is asking you this. This will enable you to provide the right answer, assuming that you know it.

Can you use Enum to implement an interface in Java?

"Enum can implement an interface in Java since it is a type similar to a class and interface. This provides a great deal of flexibility when using Enum as a specialized implementation."

As the interview progresses, the interviewer will ask you a series of technical and operational questions. The purpose behind these is to test your knowledge of the technology and learn how you do this job. Interviewers seek to confirm your qualifications and determine if you have the skills and experience needed to perform the duties described in the job description.

When you recognize a question as technical or operational, you should immediately structure your answer to be brief and to the point. Interviewers expect direct answers to their questions and a response that provides them with the information they are seeking. They will ask a follow-up question if they need additional information or want to explore the topic in more detail.

Can Enum extend a class in Java?

"Enum cannot extend the class in Java, even though it is a type as a class or interface in Java. Since Enum extends abstract base class java.lang by default, it cannot extend another class. This is because Java doesn't support multiple inheritances for classes."

Knowing the constraints and capabilities of any technology is key to being successful as a Java programmer. Interviewers will ask a lot of questions about the capabilities of a technology to determine if you understand these. Programmers who don't understand the capabilities and constraints of the technology waste a great deal of time experimenting with these. This costs the organization both time and money. Therefore, interviewers will ask questions like this to confirm that you understand these limitations.

Assuming that you have experience using Enum in your Java programming, questions like this should be easy for you to answer. However, it is still recommended that you review Enum before attending an interview for a Java programmer's job so that the concepts are fresh in your mind. Practicing questions like this will also help you prepare for the interview and ensure that you perform to your absolute best.

Can you discuss the differences between ordinal() and compareTo() in Enum?

"CompareTo() mimics the ordering provided by the ordinal() method. This is the natural order of Enum. Enum constraints are compared in the order they were originally declared. Also, Enum constants are only comparable to other Enum constants of the same Enum type. Therefore, comparing an Enum constant of one type to another type will result in a compiler error."

If this question looks familiar, it is probably because it is a follow-up to a question the interviewer asked earlier in the interview. Interviewers ask follow-up questions for two reasons. One is to explore a topic in more detail. The other is to correlate your answers to ensure you are consistent throughout the interview.

Once you recognize a question as a follow-up to a previous question, you should try to refresh your memory as to how you answered the previous question and try to answer this one similarly. This will demonstrate your consistency to the interviewer. Suppose the interviewer continues to ask questions about this topic. In that case, it indicates that it is important to their organization, and you should enlarge your answers to give them more in-depth information about the topic.

Is Enum typically used with TreeSet or TreeMap in Java?

"The main requirement for using a sorted collection like TreeSet and TreeMap is the implementation of a comparable interface. Since Enum implements a comparable interface by default, it can be safely used inside TreeSet or TreeMap in Java."

Since Enum was only incorporated in Java's most recent iterations, not all Java programmers are up to speed on the technology. This is why interviewers will ask a series of questions to determine your level of knowledge about this topic. They're trying to understand if you are only casually knowledgeable and have limited exposure to Enum or if you use it in your everyday programming.

Since interviewers have been professionally trained to determine your qualifications for a job, they can usually discern whether your knowledge is casual or in-depth about a particular topic. This is why you should always be honest when responding to an interviewer's questions. Attempting to exaggerate your qualifications may get you through the interview, but keep in mind you are expected to perform on the job. This is why it is recommended that you cooperate with the interviewer so you can both determine if this job is appropriate for your skill level.

What is the ordinal() method used for in Enum?

"The ordinal method is used to return the order in which Enum instances are declared inside Enum. An example of this is declaring the months of the year in order using MonthsOfYear. This will result in the months being returned in order, beginning with January and ending with December."

Interviewers will ask Java programmers very specific questions about the technology and processes used to create a software program. They want to ensure that the candidate is familiar enough with the jargon programmers use to interpret their questions and provide the information they seek. This methodology enables interviewers to select only the best and most knowledgeable candidates and eliminate ones who do not have the knowledge and skills required by the job.

When preparing for an interview for a Java programmer's role, you need to spend a great deal of time reviewing the terminology, processes, and procedures used in this job. Being familiar with the jargon, acronyms, and other terminology used when creating Java software will help you understand the interviewer's questions and provide them with the information they are seeking by asking them.

Can a constructor be declared inside Enum in Java?

"You can declare a constructor inside of Enum when coding in Java. However, you can only declare a private or package-private constructor inside Enum. Public and other protected constructors are not allowed inside of Enum."

When you are interviewing for a role with a specific focus, the interviewer's questions may sound similar to each other. Interviewers tend to use similar constructs and formats when creating questions for the interview. Like most people, they follow patterns in their job. Doing this helps interviewers simplify the process of creating the questions and conducting the interview.

It is critically important that you listen very carefully to the interviewer's questions. Since they use similar formats for their questions, you may get confused about what the interviewer is asking you about. Failing to answer the interviewer's question with the information they seek may be interpreted as you not knowing the information rather than not understanding the question. If you are in doubt, it is okay to ask a clarifying question to determine what the interviewer is seeking to learn.

Are you able to create an instance of Enum outside of Enum itself?

"Enum instances cannot be created outside of the Enum boundary. This is because Enum doesn't have a public constructor. The compiler generates a lot of code in response to the Enum type declaration and therefore doesn't allow public constructors inside Enum. This requires you to declare Enum instances inside Enum itself."

While interviewers typically ask you questions about Enum within the context of an interview for a Java programmer's position, they can include these in interviews for other roles. This is because Enum can be used in other programming languages such as C and C++. Additionally, not all the questions you'll be asked during an interview for a Java programmer's role will be about Enum.

You can never determine the exact questions an interviewer will ask you, but your research should give you a good idea of the topics the interviewer will cover. Sources of the information you can use to determine this include the job posting, the organization's website, and conversations with current and former employees performing the same job. The more in-depth your research, the better you will perform during the interview.

Is it possible to override the toString() method for Enum? What would happen if you didn't do this?

"Yes, you can override toString in Enum. Similar to other classes, it also extends the Java.lang object and has the toString() method available. However, even if you don't override, your code won't be impacted. This is because the abstract base class of Enum does that for you and 'returns name,' which is the name of the Enum instance itself. This is a constructor of creating Enum, which is called by code and generated by the compiler in response to Enum type declaration in a Java program."

As the interview progresses, the technical questions will become more challenging. This indicates that the interviewer has gained confidence in your capabilities and wants to test your knowledge and skills in more depth. Since many interviewers follow predefined scripts, you may be able to predict when the questions will begin to become progressively more difficult.

As the questions become more difficult during an interview, you may encounter a few that you can't answer. Rather than try to bluff your way through these, the best strategy is to admit this to the interviewer and then demonstrate how you would find the information they are asking about. Interviewers will appreciate your honesty and your ability to locate the information. They are trained to determine when you are fabricating an answer and can immediately call you out on this.

Is it possible to create Enum without any instance and without a compile-time error?

"You can create Enum without any instance in Java. An example of this is creating a utility class, which is another way of using Enum when coding in Java. This doesn't require the use of defined constants such as colors or notes on a scale which are common in other uses of Enum."

Interviewers sometimes ask you tricky questions that are ambiguous or may have multiple answers. Some interviewers do this to trick you, while others want to see how flexible you are when responding to a difficult question. Since an interviewer's job is to learn as much as they can about you to see if you're qualified for the position for which they are interviewing you, they're more likely to be interested in your flexibility rather than trying to make you fail.

Regardless of the rationale behind the interviewer's question, your answer should be consistent throughout the interview. Technical and operational questions should be answered directly and briefly. Embellishing your answers may indicate that you are not confident in your initial response and are trying to cover this up by adding additional information.

Is Enum used in the switch case in Java?

"You can use Enum in the switch case in Java, which is one of the advantages of using this technology. This is because instances are compile-time constant. One of the reasons that Enum and switch cases work well with each other is that it has a relatively small number of fixed constants."

Since the job you're interviewing for requires the use of Enum in your Java coding activities, the interviewer expects you to have in-depth knowledge of the technology. They are likely to ask you a series of technical questions about the capabilities of Enum and when it can be used in special situations. Being able to respond to these will help you demonstrate your qualifications to the interviewer and increase the likelihood that they will offer you a job.

Since you are interviewing for a job that requires the use of Enum in your Java coding, it is advisable that you spend a great deal of time either learning about its capabilities or refreshing your knowledge of these before the interview. Doing this will keep the information in the front of your mind and enable you to respond to the interviewer's questions quickly and authoritatively. Interviewers not only evaluate the accuracy of your answers, but they also are sensitive to how confidently you respond to their questions.

Enum Java Programmer Interview Questions

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1. Can you discuss what Enum is and provide an example?
2. What are some of the advantages of using Enum when coding in Java?
3. What are some advantages of using Enum over Enum int pattern and Enum string pattern?
4. Can you talk about the advantages of using Enum as Singleton?
5. What are some of the benefits of using Enums in Java?
6. Why would a Java programmer incorporate the concept of Enum into their code?
7. What is the process for iterating over all instances of an Enum?
8. Walk me through how you would convert a string to Enum in Java?
9. Are Enum constants considered to be static and final?
10. What is the default value for Enum's serialVersionUID?
11. Is Enum serializable in Java?
12. Is it possible for an Enum constructor to be declared public in Java?
13. Are Enums considered to be a reference type in Java?
14. Can you create an Enum without constants?
15. Can you describe an Enum ordinal in Java?
16. Is it possible for Enum to have a main method in Java?
17. Can you define the term 'Enumeration' and discuss what it is used for when creating code in Java?
18. Can an object be created of Enum?
19. Is it possible to extend an Enum to add elements?
20. Is it possible to declare Enum constants as static and final?
21. Can you use Enum to implement an interface in Java?
22. Can Enum extend a class in Java?
23. Can you discuss the differences between ordinal() and compareTo() in Enum?
24. Is Enum typically used with TreeSet or TreeMap in Java?
25. What is the ordinal() method used for in Enum?
26. Can a constructor be declared inside Enum in Java?
27. Are you able to create an instance of Enum outside of Enum itself?
28. Is it possible to override the toString() method for Enum? What would happen if you didn't do this?
29. Is it possible to create Enum without any instance and without a compile-time error?
30. Is Enum used in the switch case in Java?

Enum Java Programmer Interview Questions

1. Can you discuss what Enum is and provide an example?

2. What are some of the advantages of using Enum when coding in Java?

3. What are some advantages of using Enum over Enum int pattern and Enum string pattern?

4. Can you talk about the advantages of using Enum as Singleton?

5. What are some of the benefits of using Enums in Java?

6. Why would a Java programmer incorporate the concept of Enum into their code?

7. What is the process for iterating over all instances of an Enum?

8. Walk me through how you would convert a string to Enum in Java?

9. Are Enum constants considered to be static and final?

10. What is the default value for Enum's serialVersionUID?

11. Is Enum serializable in Java?

12. Is it possible for an Enum constructor to be declared public in Java?

13. Are Enums considered to be a reference type in Java?

14. Can you create an Enum without constants?

15. Can you describe an Enum ordinal in Java?

16. Is it possible for Enum to have a main method in Java?

17. Can you define the term 'Enumeration' and discuss what it is used for when creating code in Java?

18. Can an object be created of Enum?

19. Is it possible to extend an Enum to add elements?

20. Is it possible to declare Enum constants as static and final?

21. Can you use Enum to implement an interface in Java?

22. Can Enum extend a class in Java?

23. Can you discuss the differences between ordinal() and compareTo() in Enum?

24. Is Enum typically used with TreeSet or TreeMap in Java?

25. What is the ordinal() method used for in Enum?

26. Can a constructor be declared inside Enum in Java?

27. Are you able to create an instance of Enum outside of Enum itself?

28. Is it possible to override the toString() method for Enum? What would happen if you didn't do this?

29. Is it possible to create Enum without any instance and without a compile-time error?

30. Is Enum used in the switch case in Java?