Classes

DateTimeOffSet values are often converted to strings for display or some other purpose. But these representations often fail when they are used to convert them back to valid date/time values.

Calendar c = Calendar.getInstance(); c.set(2017, Calendar.OCTOBER, 29);  This code behave as a Gregorian calendar, but if the returned Calendar subclass is a Islamic, Julian, Buddistic or Hebrew calendar, then the month called October or the year 2017, doesn’t exist. Calendar.getInstance() uses the current default locale to select an appropiate implementation. The utility of Calendar.getInstance() is very limited  and it should be avoided because it’s results is not properly defined. Calendar c = new GregorianCalendar (timeZone); c.set(2017, Calendar.OCTOBER, 29); 

We can use the Random class available in the java.util package to generate random numbers. The code sample below demonstrates generation of a random number with an upper limit. Listing

StringBuffer is a class that facilitates string operations and also helps reduce memory usage. A method defined on StringBuffer named setLength(int newLength) also serves as a shortcut to clear the

The String class facilitates finding the unicode of characters in a String using the codePointAt method. Listing 1. Finding Unicode Characters public class StringCodePoint{ public static void main(String args[]) {

Using underscores in numerals is allowed in Java. This is for better readability and representation. The example below illustrates the same value being written in two different forms and results

Optional makes it easier in cases where the result is not really needed. This example can be fine-tuned as needed to explore all of the methods supported. import java.util.Optional;public class

String.join is an easy-to-use utility method in String class. public class StringJoin{ public static void main(String args[]){ //The first argument (refered as joinString) is used to join the subsequent argument(s)

The code in String.cpp can be used to do basic operations based on character array. It can also be used to see some of the extra flavors of Object Oriented