Consider a table with a stack of plates. After the first one is placed on the table, the next one is placed on top of it; the third one is placed on top of the second, and so on, until the desired number is reached. To take the dishes off the table one by one, start with the last one placed on top; then move on to the last-but-one; then the one next to the top; and so on.
StringBuilder is a Java class that allows you to generate a mutable, or changeable, sequence of characters. The StringBuilder class, like StringBuffer, is an alternative to the Java Strings class, which provides an immutable sequence of characters. However, there is a critical distinction between StringBuffer and StringBuilder: the latter is non-synchronized.
The Scanner is a class in java.util package. This class is responsible for reading data from a string, the keyboard, a file, or a network socket. This article focuses solely on reading the keyboard input and displaying the output in a terminal window. Reading data from a file or a network channel is done similarly.
With the help of examples, you will learn how to utilize the switch statement in Java to regulate the flow of your program’s execution. The switch statement lets us choose several different ways to run a code block. The switch statement in Java has the following syntax:
The Math.random() method is one of Java’s most commonly used methods for generating a random numeric number. The java.lang class is a built-in class in Java.Math with several mathematical procedures, one of which is Math.random(). Because the Math.random() method is a static method, it can be invoked/called without first constructing a math class instance—the java.lang.Math class offers several methods for performing basic numeric operations such as the exponential, logarithm, square root, and trigonometric functions.
Changing the date format of a given Date or String is a typical Java programming task. For example, suppose you have “2022-05-22 12:00:00” and want to convert it to “2022-05-22,” or convert from dd-MM-YY to MM-dd-YY, or any other format you like, as long as it is a valid date format as defined by Java. How will you accomplish this? It’s not that difficult, after all. It’s a simple two-step procedure.
In Java, getting the current timestamp is simple. We’ll learn how to acquire the timestamp using the Date and Timestamp classes in this lesson. This article provides some Java examples for obtaining the current date, time, or timestamp. In addition, Java 8 has been included.
Besides the AbstractMap Class, Java’s TreeMap discreetly implements the Map interface and NavigableMap. Depending on which constructor is used, the map is sorted either by the natural ordering of its keys or by a Comparator specified at map creation time.
In Java, encapsulation combines data (variables) and code that acts on the data (methods) into a single unit. Encapsulation means that a class’s variables are concealed from other classes and can only be accessed through its current class’s methods. Consequently, it’s also known as data concealment.
The Set interface has its implementation handled by the HashSet class, supported by a hash table that is a HashMap instance. The iteration order of the Set is not guaranteed, which means that the class does not guarantee the same order of elements across time.
The Java ternary operator allows you to build a single-line if statement. True or false can be the result of a ternary operator. Whether the statement evaluates to true or false, it returns a certain result.
Since Java 1.2, HashMap