While writing an interface/class names you need to keep the following points in mind. First letter of the interface/class name should be capital and remaining letters should be small (mixed case). interface Sample Likewise, first letter of each word in the name should be capital an remaining letters should be small. interface MYInterface Keeping interface names simple and descriptive is suggestable. Better not to use acronyms while writing interface/class names. Example Live Demo interface MyInterface { void sample(); void demo(); } ... Read More

Declaring a constructor is in Java is similar to methods. While naming the constructor of a class in Java you need to keep the following points in mind. The name of the constructor should be the same (same case) as the class name (along with the access specifier). A constructor should not have any return type. Constructor cannot be static, final, abstract and, synchronized. Example Following Java program is an example of a constructor. Live Demo public class Sample { Sample() { System.out.println("This is an example of ... Read More

Main method is the entry point of the execution in Java. When we execute a class JVM searches for the main method and execute the contents of it line by line. If you observe the following example you can compile a this program but if you try to execute it you will get an error saying “Main method not found”. Example abstract class SuperTest { public abstract void sample(); public abstract void demo(); } public class Example extends SuperTest{ public void sample(){ System.out.println("sample method ... Read More

You can return only one value in Java. If needed you can return multiple values using array or an object. Example In the example given below the calculate() method accepts two integer variables performs the addition subtraction, multiplication and, division operations on them stores the results in an array and returns the array. public class ReturningMultipleValues { static int[] calculate(int a, int b){ int[] result = new int[4]; result[0] = a + b; result[1] = a - b; ... Read More

Yes, we can write a method using variable arguments once you use variable arguments as a parameter method while calling you can pass as many numbers of arguments to this method (variable number of arguments) or, you can simply call this method without passing any arguments.ExampleLive Demopublic class Sample{    void demoMethod(String... args) {       for (String arg : args) {          System.out.println(arg);       }    }    public static void main(String args[] ){       new Sample().demoMethod("ram", "rahim", "robert");       new Sample().demoMethod("krishna", "kasyap");       new Sample().demoMethod();    } }Outputram rahim robert krishna kasyap

If a function is inline, the compiler places a copy of the code of that function at each point where the function is called at compile time. Any change to an inline function could require all clients of the function to be recompiled because compiler would need to replace all the code once again otherwise it will continue with old functionality. No, Java does not provide inline functions it is typically done by the JVM at execution time.

Following are the notable differences between non-static methods and abstract methods.Non-static (normal) methodsAbstract methodsThese methods contain a body.Abstract methods don’t have body these are ended with a semicolonYou can use normal method directly.You cannot use abstract methods directly, to use them you need to inherit them and provide body to these methods and use them.Example:public void display() {    System.out.println("Hi"); }Example:public void display();

For this purpose, we create an object of HashMap class which is defined in java.util packageMap map = new HashMap();This hashmap object associates each digit with its corresponding word representationmap.put("0", "zero");Initialize an empty string object.String newstr="";Next, run a for loop over the length of given string and extract each character by substring() method of String class.Check if the character exists as a key in map object by containsKey() method. If it does, using it as key, obtain its value component in map and appenf\d to the new string. If not append the character itself to the new string. The complete code ... Read More

While choosing an identifier to declare a variable in Java you need to keep the following points in mind. The name of the variable should begin with either alphabet or, an underscore (_) or, a dollar ($) sign. The identifiers used for variables must not be keywords. No spaces or special characters are allowed in the variable names of Java. Variable names may contain 0 to 9 numbers (if not at the beginning). Variable names are case sensitive i.e. MY_NUM is different from my_num. If you use two words in a identifier then the you should follow camel case ... Read More

While writing a method name we should follow the camel case i.e. first letter of the first word should be small and the first letters of the remaining (later) words should be capital. Example public class Test { public void sampleMethod() { System.out.println("This is sample method"); } public void demoMethod() { System.out.println("This is demo method"); } public static void main(String args[]) { Test obj = new Test(); obj.sample(); obj.demo(); } } Output This is sample method This is demo method