OCP Oracle Certified Professional Java SE 17 Developer Study Guide. Jeanne Boyarsky

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Introduction

      This book is for those looking to obtain an Oracle Certified Professional: Java SE 17 Developer or Java Foundations Certified Junior Associate title. This book is also for those looking to gain a deeper understanding and appreciation of Java. Not only do we want you to pass your exams, but we also want to help you to improve yourself and become a better professional software developer.

      The book provides detailed preparation for the following Oracle certification exams:

       1Z0-829 Exam: Java SE 17 Developer The Developer exam covers a wide variety of core topics in Java 17 including classes, interfaces, streams, collections, concurrency, and modules.

       1Z0-811 Exam: Java Foundations The Foundations exam is a junior-level certification exam that contains a variety of introductory and basic Java 8 topics.

      In this introduction, we start by covering important information about the various exams. We then move on to information about how this book is structured. Finally, we conclude with an assessment test so you can see how much studying lies ahead of you.

Understanding the Exam

      At the end of the day, the exam is a list of questions. The more you know about the structure of the exam, the better you are likely to do. For example, knowing how many questions the exam contains allows you to better manage your progress and time remaining. In this section, we discuss the details of the exam, along with some history of previous certification exams.

      Choosing Which Exam to Take

      Java is now over 25 years old, celebrating being “born” in 1995. As with anything 25 years old, there is a good amount of history and variation between different versions of Java. Over the years, the certification exams have changed to cover different topics. The number of exams and names of certifications have also changed.

      For Java 17, Oracle has simplified things. Becoming an Oracle Certified Professional now requires passing only one exam, not two, and there are no Java 17 upgrade exams. Regardless of the previous certifications you hold, everyone takes the same, single Java 17 exam to become an Oracle Certified Professional.

      This means your only choice is between the Java 17 OCP exam and the Java Foundations exam. Our advice is to only take the Java Foundations exam if your employer has specifically asked you to. While it is an easier exam, it targets a very old version of Java and is not meant for professionals who work with Java every day.

      Considering the Exam Objectives

      Oracle provides a list of objectives to guide you on what to study for each exam. Each objective defines a list of subobjectives that provide additional details about the objective. Unfortunately, the objectives don't encompass the full amount of material needed to pass the exam.

      So how do you know what to study? By reading this study guide, of course! We've spent years studying the certification exams in all of their forms and have carefully cultivated topics, material, and practice questions that we are confident can lead to successfully passing the exam. More recently, we've worked hand-in-hand with Oracle helping to create and refine the objectives and material for the Java 11 and Java 17 exams.

      As a starting point, you should review the list of objectives presented in this introduction and mark down the ones that are unfamiliar to you. This list, along with the Assessment Test at the end of this introduction, will give you a rough idea of how much you are going to need to study for the exam.

      Changes to the Exams

Table I.1 shows the information about the exams at the time of publishing.

TABLE I.1 Exam information

Exam	Length	# of Questions	Passing Score
1Z0-829 Java SE 17 Developer	90 minutes	50	68%
1Z0-811 Java Foundations	150 minutes	75	65%

      Oracle has a tendency to fiddle with the length of the exam and the passing score once it comes out. Oracle also likes to “tweak” the exam objectives over time. It wouldn't be a surprise for Oracle to make minor changes to the exam objectives, the number of questions, or the passing score after this book goes to print.

      If there are any changes to the exam after this book is published, we will post them on the book page of our blog:

       www.selikoff.net/ocp17

      Scope of Objectives

In previous certification exams, the list of exam objectives tended to include specific topics, classes, and APIs that you needed to know for the exam. For example, take a look at an objective for the OCP 8 exam (1Z0-809):

       Use BufferedReader, BufferedWriter, File, FileReader, FileWriter, FileInputStream, FileOutputStream, ObjectOutputStream, ObjectInputStream, and PrintWriter in the java.io package.

      Now compare it with the equivalent objective for the OCP 17 exam (1Z0-829):

       Read and write console and file data using I/O Stream.

      Notice the difference? The older version is more detailed and describes specific classes you need to understand. The newer version is a lot vaguer. It also gives the exam writers a lot more freedom to insert a new feature without having to update the list of objectives.

      Choosing the Correct Answer(s)

      Each exam consists entirely of multiple-choice questions. There are between four and seven possible answers. If a question has more than one answer, the question specifically states exactly how many correct answers there are. This book does not do that. We say Choose all that apply to make the questions harder. This means the questions in this book are generally harder than those on the exam. The idea is to give you more practice so you can spot the correct answer more easily on the real exam.

      Reading the Exam Code

      Many of the questions on each exam are code snippets rather than full classes. Saving space by not including imports and/or class definitions leaves room for lots of other code. You should only focus on import statements when the question specifically asks about them.

      For example, it is common to come across classes on the exam with import statements and portions omitted, like so:

      public class Zoo implements Serializable { String name; // Getters/Setters/Constructors omitted }

      In this case, СКАЧАТЬ