Java Virtual Machine (JVM)

All language compliers translate source code into machine code for a specific computer. Java complier also do the same things but Java compiler produce an intermediate code known as bytecode. This machine is called as Java Virtual Machine(JVM) and it is exists only inside the computer memory with java. It is simulated computer within computer and does all major functions of real computer.

The virtual machine code is not machine specific. The machine specific code is generated by the Java Interpreter by acting as an intermediary between the virtual machine and the real machine. The interpreter is different for different machine.

The java object framework acts as the intermediary between the user program and virtual machine which turns act as the intermediary between operatinf system and the java object framework.

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Decision Making and Branching Statements / Control Statements

Introduction Java is a set of statements which executed sequentially in the order in which they appear. This will happen when option or repetitions of certains are not necessary. However, We have a number of situation, where we may have to change the order of execution of statement on bases of certain conditions. This involves a kind of dicision making to see the particular condition occured or not and the direction of execution will execute according to it. When program braks the sequential flow and jump on the another part of code then it's called branching . When branching is on particular condition then it's called conditional branching . If branches executes without any particular conditions then it's call unconditional branching . Java supports such decision making capabilities and supports following statements known as Control statement or Decision making statement . if statements switch statement ...

Static and this keyword

Static Keyword: Most of the time static keyword in java use for memory management. We can use static keyword with variables, methods and also with block (Static block) . 1. Static with variables: If we declare static keyword with variables then it's called static variables . Static variables are use to access or refer common properties of all objects. The static varibels gets memory only once at the time of loading class loading. It makes program more efficient i.e., It saves memory. For example, static int length=100; 2. Static with method: If we use static keyword with method then it's called static method . The static method is belong to class rather than object of class. Static method can invoke or call without creating instance or object of class. For example, static void print(){ System.out.println("Welcome in Java"); } Examples of static variable, method an...

Jump Statements in java

Introductions Loopes perform a set of operations repeatedly until the control variable fails to satisfy the test condition. But in some times we need to skip some of the part of loop then we use the jump statements . For breaking the loop we use continue and break statement . Continue Statement: When the continue statement called, it will break or stop the current itteration of loop on sameline and start the new iteration. Format of this statement is below: continue; Brak Statement: After call this statement in the body of loop, it will sop or break the loop on current loop on same line and control goes to the next line after that loop. Format is below: break; We mostly use this statement in while, do, and for loop concept.

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