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Everything You Need to Know About Java Certification

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Everything You Need to Know About Java Certification

Kick your programming career up a notch.

· Java Zone ·
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Thinking of beginning your career in programming? Not a bad idea, as there’s a high demand for programmers today. Also, being certified in a technology or programming language can considerably increase the chances of employment and improve your skills. One of the most widely used programming languages is Java, and thus, Java programmers are in high demand all around the world. If you are looking to get a Java certification, you can get it from Oracle.

Getting this certification is not that difficult or expensive. Once you’re certified, you can make your own applications, games, etc. You can use coupons from GoDaddy to host your Java app; these coupons can help you save a decent amount of money when launching your app. You can also use coupons to purchase the test preparation material, or when booking the test, you can save a decent amount of money on the test.

The Java certification from Oracle tests your knowledge and skills in the Java programming language. If you pass this test, it certifies that you have ample knowledge to program software in the Java language. It can be considered a benchmark of Java knowledge and expertise.

Oracle is the company behind the Java language, so their certification carries a lot of weight. Previously, there used to be just one test for the Java certification. However, now Oracle has divided the certification into two parts:

Oracle Certified Associate (OCA)

This is an entry-level certification designed for beginners to intermediate level Java programmers. It certifies that you have covered all the basics of the programming language. It covers the very basics as well as some advanced topics including polymorphism, inheritance, abstract classes, and APIs. The basics would include variable, data types, access modifiers, methods, and exceptions.

Here are the topics covered in this test:

Java Basics

Look at a simple code printing “Hey Dear” in the Java program:

public class FirstJavaProgram {

   /* This is my first java program.
    * This will print 'Hey Dear' as the output
    */

   public static void main(String []args) {
      System.out.println("Hey Dear"); // prints Hey Dear
   }
}


Working With Java Data Types

Java is statically typed and also a strongly typed language and has the following types of data:

public static void main(String[] args) {
byte byteDataType =10;
short shortDataType =12;
int intDataType = 12753;
int calc = -87635;
long longDataType = 123456789;
float floatDataType = 12.42f;
double doubleDataType = 12345.234d;
boolean flag = true;
boolean val = false;
           char charDataType = 'Z';

           System.out.println("byteDataType");
           System.out.println("shortDataType");
           System.out.println("intDataType");
           System.out.println("calc");
           System.out.println("longDataType");
           System.out.println("floatDataType");
           System.out.println("doubleDataType");
           System.out.println("flag");
           System.out.println("val");
           System.out.println("charDataType");

}


Creating and Using Arrays

You can create an array when you store a large number of data by using the new operator; we often use either a for loop or foreach loop. 

public static void main(String[] args) {
    // declares an array of integers
    int[ ] Y;

    // allocates memory for 3 integers
    A = new int[3];

    // initialize elements
    A[0] = 30;//first element

    A[1] = 40;//second element

    A[2] = 55;//third element


    System.out.println("Element at index 0: "
                       + A[0]);
    System.out.println("Element at index 1: "
                       + A[1]);
    System.out.println("Element at index 2: "
                       + A[2]);

}
Output:
Element at index 0: 30
Element at index 1: 40
Element at index 2: 55


Using Loop Constructs

Syntax of While Loop 

In Java, you can use the while loop if the number of iteration is not fixed.

while (i <= 5)
{
        loop statements….
i++;
}


Syntax of For Loop

In Java, you can use the For loop if the number of iteration is fixed.

for (int i = 1; i <= 5; i++)
{
Statement(s)
}


Syntax of Do While Loop

In Java, you can use a do while loop if the number of iteration is not fixed, and you must execute the loop at least once.

Do
{
Statements…
}
While(condition);


Working With Inheritance

This is the most significant mechanism in Java by which one class is allowed to inherit the features of another class.  

class Teacher {
 void Teacher_Details() {
  System.out.println("Teacher Details...");
 }
}

class Student extends Teacher {
 void Student_Details() {
  System.out.println("Student Detail...");
 }
}


Working With Methods and Encapsulation

This is how we achieve encapsulation in Java when we wrap code and data in a single unit. 

// Java program to demonstrate encapsulation 
public class Encapsulate 
{ 
    // private variables declared  
    // these can only be accessed by  
    // public methods of class 
    private String yourName; 
    private int yourRoll; 


    // get method for name to access  
    // private variable yourName 
    public String getName()  
    { 
      return yourName; 
    } 

    // get method for roll to access  
    // private variable yourRoll 
    public int getRoll()  
    { 
       return yourRoll; 
    } 


    // set method for name to access  
    // private variable yourName 
    public void setName(String newName) 
    { 
      yourName = newName; 
    } 

    // set method for roll to access  
    // private variable yourRoll 
    public void setRoll( int newRoll)  
    { 
      yourRoll = newRoll; 
    } 
program to access variables of the class Encapsulate

public class TestEncapsulation 
{     
    public static void main (String[] args)  
    { 
        Encapsulate obj = new Encapsulate(); 

        // setting values of the variables  
        obj.setName("Oscar"); 
       obj.setRoll(51); 

        // Displaying values of the variables 
        System.out.println("Your's name: " + obj.getName()); 
        System.out.println("your's roll: " + obj.getRoll()); 

        // Direct access of yourRoll is not possible 
        // due to encapsulation 
        // System.out.println("Geek's roll: " + obj.geekName);         
    } 
} 
Output:
Your’s name: Oscar
Your’s roll: 62


Oracle Certified Professional (OCP)

This certification takes the OCA to the next level and covers advanced topics as well. These may include JDBC, generics, threads, and file I/O. You need to have some sort of training to be able to pass this certification. It is designed for those who already have prior Java programming experience.

You need to cover the following topics and have full knowledge of:

Image title

 What Is the Java Certification Test Like?

The test consists of simple and multiple choice questions with varying levels of difficulty. Most of the questions have coding snippets that you need to answer questions about. You may have questions about code examples asking if it will successfully compile or not. You may have to point out other mistakes in the code.

The simple questions have radio buttons and you just have to choose one answer. On the other hand, multiple choice questions have checkboxes and you can select multiple answers. The test is taken on a computer and no other material is allowed to be accessed except for a scrap paper and pen. Each question only has two minutes.

In the professional exam, some questions can be more difficult and require more time. For example, does the following class effectively prevent other classes to modify its data?

public class GetterSetter {
          Private List<String> data;
    public List<String>  getData() {
      return data;
}
    public void setData(List<String> data) {
     this.data =  data;
       }
}


There may be one snippet of code within a question or multiple as part of the answers. The code will be more advanced in the professional certification exams as it covers more advanced topics.

Benefits of Java Certification

There are many benefits to getting certified in a programming language, especially Java because it is used in so many applications. Here are some benefits of getting certified in Java:

Improved Skills

In preparation for the test, and in the test itself, you will end up improving and polishing your programming skills. But not just programming; you will also work on your problem-solving and analysis skills. Some questions are more theoretical, so you will be required to study all of the concepts. In short, this exam would cover all the aspects of the language.

When you take this exam, you will be fully versed in all those aspects provided you have studied for it. In fact, you may even learn things you have not covered before in class.

Better Job Opportunities

Of course, the biggest benefit of getting certified in any language or skill is getting a better job opportunity. Even though many companies do not necessarily require potential candidates to be certified, they prefer employees to be certified. The certification is proof of their knowledge and training in the said language.

Recognition of Your Abilities

It is good to get certified as it serves as a stamp of your ability to be a developer in a certain language. And of all the languages, being great at Java is an achievement in its own right. The Oracle Java Certification is considered one of the most recognized certifications globally. So not only will your talent and skills be recognized in your organization but all over the world.

Teach Java

With a certificate in your hand, you can also become a Java instructor. Depending on the teaching level, you can make some good money. The best part is that you will be giving all the knowledge to young programmers. Having an Oracle Java Certificate will improve your chances at being hired as an instructor at a higher education institute.

Conclusion

If you have been studying and using the Java language for some time now, you may want to get certified in the language. Surely, it is an investment in your career and will allow you to tap into better opportunities. Even if you are already working as a Java developer, you can get certified to further climb the ladder.

For beginners, the first test is more suitable. However, for those who are experienced in Java development and have covered almost all topics, professional certification is better — anyone can apply for these tests. There is a lot of material online that can help you prepare for the test.

Topics:
java (programming lang... ,java ,java basics

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