Online Core Java Training1

1. Online Core Java Training INTRODUCTION: CORE JAVA TRAINING was developed by James Gosling at Sun Microsystems Inc in the year 1995, later acquired by Oracle Corporation. It is a simple programming language. Java makes writing, compiling, and debugging programming easy. It helps to create reusable code and modular programs. Java is a class-based, object-oriented programming language and is designed to have as few implementation dependencies as possible. A general-purpose programming language made for developers to write once run anywhere that is compiled Java code can run on all platforms that support Java. Java applications are compiled to byte code that can run on any Java Virtual Machine. The syntax of Java is similar to c/c++. OVERVIEW: Java programming language was originally developed by Sun Microsystems which was initiated by James Gosling and released in 1995 as core component of Sun Microsystems' Java platform (Java 1.0 [J2SE]). The latest release of the Java Standard Edition is Java SE 8. With the advancement of Java and its widespread popularity, multiple configurations were built to suit various types of platforms. For example: J2EE for Enterprise Applications, J2ME for Mobile Applications. The new J2 versions were renamed as Java SE, Java EE, and Java ME respectively. Java is guaranteed to be Write Once, Run Anywhere. CORE JAVA TERMINOLOGY: 1. Java Virtual Machine(JVM): This is generally referred to as JVM. There are three execution phases of a program. They are written, compile and run the program. Writing a program is done by a java programmer like you and me. The compilation is done by the JAVAC compiler which is a primary Java compiler included in the Java development kit (JDK). It takes the Java program as input and generates bytecode as output. In the Runningphase of a program, JVM executes the bytecode generated by the compiler. Now, we understood that the function of Java Virtual Machine is to execute the bytecode produced by the compiler. Every Operating System has a different JVM but the output they produce after the

2. execution of bytecode is the same across all the operating systems. This is why Java is known as a platform-independent language. 2. Bytecode in the Development process: As discussed, the Javac compiler of JDK compiles the java source code into bytecode so that it can be executed by JVM. It is saved as .class file by the compiler. To view the bytecode, a disassembler like javap can be used. 3. Java Development Kit(JDK): While we were using the term JDK when we learn about bytecode and JVM. So, as the name suggests, it is a complete Java development kit that includes everything including compiler, Java Runtime Environment (JRE), java debuggers, java docs, etc. For the program to execute in java, we need to install JDK on our computer in order to create, compile and run the java program. OBJECTIVES: 1. Why Java is platform independent? Java is called platform independent because of its byte codes which can run on any system irrespectiveof its underlying operating system. 2. Why Java is not 100% Object-oriented? Java is not 100% Object-oriented because it makes use of eight primitive data types such as boolean, byte, char, int, float, double, long, short which are not objects. 3. What are wrapper classes in Java? Wrapper classes convert the Java primitives into the reference types (objects). Every primitive data type has a class dedicated to it. These are known as wrapper classes because they “wrap” the primitive data type into an object of that class. Refer to the below image which

3. displays different primitive type, wrapper class and constructor argument. KEY FEATURES: -Flexible Timings | Certified & Industry Experts Trainers - Customize Course | Multiple Training Delivery Models -24/7 Support | Hands-On Experience -Real-time Use Cases | Q&A with Trainers -Small Batches (1to5) | Flexible Payments Contact info: USA: +1 (818) 665 7216 INDIA: +91 9711699759 Email: sales@hkrtrainings.com