What is overloading?

Overloading enables a user to use the same name for different subprograms within a PL/SQL block, subprogram, or package. Overloading subprograms requires the formal parameters of the subprograms to differ in number, order, or datatype family. Oracle server determines the subprogram to be called......[read more]

What is the default value of the elements of an array?

As soon as an array is created using a new operator, its elements are automatically initialized to their default values. This automatic initialization of the elements depends on the data type of the array. The table given below shows the initial value of the elements of an array: Element......[read more]

What is the hashCode() method?

The hashCode() method is defined in the java.lang.Object class. It returns the hash code of the invoking object. The hash code value returned by this method is a number of type int. The signature of the hashCode() method is given below: public int hashCode() Note: Objects that are equal......[read more]

What is the booleanValue() method?

The booleanValue() method is defined only in the java.lang.Boolean class and no other wrapper class. This method is used to convert the value wrapped by the Boolean object into a primitive type boolean. The method has the following signature: public boolean booleanValue() This method......[read more]

What is the parseInt() method?

The parseInt() method is a static method of the Integer class. Two versions of the parseInt() method are defined in the Integer class. Their signatures are given below: public static int parseInt(String str) throws NumberFormatException public static int parseInt(String str, int base)......[read more]

What is the replace() method?

The replace() method is a method of the String class. This method takes two character arguments. It creates a new string after replacing all the occurrences of a particular character in the string with another character. The string that invokes this method remains unchanged. The general form of......[read more]

What is the charAt() method?

The charAt() method is used to obtain a character from a string at the specified index. The general format of the method is given below: public char charAt(int location) Note: The first character in a string is at index 0 and the last character is at index length() -1....[read more]

What are keywords?

Every computer language uses some reserved words known as keywords. They are an essential part of the language. In Java, keywords are defined in lower case and cannot be used as identifiers. The table given below shows the list of keywords used in the Java language: abstract assert......[read more]

What is the random() method?

The random() method is a static method of the java.lang.Math class. It takes no argument and returns a randomly generated number of type double. A number generated by the random() method is either greater than or equal to 0.0 and less than 1.0. In other words, this can be written as follows:......[read more]

What is the Boolean class?

The Boolean class is a wrapper class that is used to wrap true or false type primitive values in a Boolean object. This class defines two constructors with the following signatures: public Boolean(boolean bool_value) public Boolean(String str) The first form of the constructor......[read more]