Star Patterns in Java
Aug 30, 2024 pm 04:24 PMIn this document, first, we will see how to use Java programming to work with Star patterns programs. Star patterns are a common Java pattern program widely used to improve logical thinking and flow control knowledge. You need to use two loops or three loops (depending on the programs) to show Star patterns in Java Programming. The first loop is the outer loop, and the second loop is the inner loop that shows rows and columns, respectively.
This document is helpful for those Java programmers who want to know about design patterns to improve their object-oriented design and development abilities.
ADVERTISEMENT Popular Course in this category JAVA MASTERY - Specialization | 78 Course Series | 15 Mock TestsExamples of Star Patterns
Let us discuss some examples to easily understand the concept of patterns in Java.
Example #1
Code:
import java.util.Scanner; public class FirstPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m = 1; m <= myrows; m++) { for (int n = 1; n <= m; n++) { System.out.print("*"); } System.out.println(); } } }
Output:
Example #2
Code:
import java.util.Scanner; public class SecondPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m = 1; m <= myrows; m++) { for (int n = myrows; n > m; n--) { System.out.print("*"); } System.out.println(); } } }
Output:
Example #3
Code:
import java.util.Scanner; public class ThirdPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m = 1; m <= myrows; m++) { for (int n = 1; n < m; n++) { System.out.print(" "); } for (int p=myrows; p>=m; p--) { System.out.print("*"); } System.out.println(); } } }
Output:
Example #4
Code:
import java.util.Scanner; public class FourthPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m = 1; m <= myrows; m++) { for (int n=myrows; n>m; n--) { System.out.print(" "); } for (int p=1; p<=(m * 2) -1; p++) { System.out.print("*"); } System.out.println(); } } }
Output:
Example #5
Code:
import java.util.Scanner; public class FifthPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m=myrows; m>=1; m--) { for (int n=1; n<=(m * 2) -1; n++) { System.out.print("*"); } System.out.println(); for (int p=myrows; p>=m; p--) { System.out.print(" "); } } } }
Output:
Example #6
Code:
import java.util.Scanner; public class SixthPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m=1; m<=myrows; m++) { for (int n=myrows; n>m; n--) { System.out.print(" "); } for (int p=1; p<=(m * 2) -1; p++) { System.out.print("*"); } System.out.println(); } for (int m=myrows-1; m>=1; m--) { for (int n=myrows-1; n>=m; n--) { System.out.print(" "); } for (int p=1; p<=(m * 2) -1; p++) { System.out.print("*"); } System.out.println(); } } }
Output:
Example #7
Code:
import java.util.Scanner; public class SeventhPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m = 1; m <= myrows; m++) { for (int n=1; n<=m; n++) { if( n == 1 || n == m || m == myrows) System.out.print("*"); else System.out.print(" "); } System.out.println(); } } }
Output:
Example #8
Code:
import java.util.Scanner; public class EighthPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m = myrows; m >= 1; m--) { for (int n = m; n >= 1; n--) { System.out.print("*"); } System.out.println(); } for (int m = 2; m <= myrows; m++) { for (int n = m; n >= 1; n--) { System.out.print("*"); } System.out.println(); } } }
Output:
Example #9
Code:
import java.util.Scanner; public class NinthPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m = 1; m <= myrows; m++) { for (int n = myrows-1; n>=m; n--) { System.out.print(" "); } for (int p = 1; p <= myrows; p++) { System.out.print("*"); } System.out.println(); } } }
Output:
Example #10
Code:
import java.util.Scanner; public class TenthPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m = 1; m <= myrows; m++) { for (int n = 1; n < m; n++) { System.out.print(" "); } for (int p = m; p <= myrows; p++) { System.out.print("* "); } System.out.println(); } for (int m = myrows-1; m >= 1; m--) { for (int n = 1; n < m; n++) { System.out.print(" "); } for (int p = m; p <= myrows; p++) { System.out.print("* "); } System.out.println(); } } }
Output:
Example #11
Code:
import java.util.Scanner; public class ElevenPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m=myrows; m>=1; m--) { for (int n=1; n <=(m * 2) -1; n++) { if( n == 1 || n == (m * 2) -1 || m == myrows) System.out.print("*"); else System.out.print(" "); } System.out.println(); for (int p = myrows; p >= m; p--) { System.out.print(" "); } } } }
Output:
Example #12
Code:
import java.util.Scanner; public class TwelthPattern { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("Please provide number of rows to print... "); int myrows = scanner.nextInt(); System.out.println("\nThe star pattern is... "); for (int m = 1; m <= myrows; m++) { for (int n = 1; n <= myrows; n++) { System.out.print("*"); } System.out.println(); } } }
Output:
Conclusion
So far, we have discussed different types of patterns in the Java programming language. These patterns are the best practices used by experienced object-oriented software designers. Users can be able to use these design patterns for the discussion of object-oriented software design. With the help of these patterns, inexperienced developers could learn software design quickly and faster.
The above is the detailed content of Star Patterns in Java. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undress AI Tool
Undress images for free

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics

The rational use of semantic tags in HTML can improve page structure clarity, accessibility and SEO effects. 1. Used for independent content blocks, such as blog posts or comments, it must be self-contained; 2. Used for classification related content, usually including titles, and is suitable for different modules of the page; 3. Used for auxiliary information related to the main content but not core, such as sidebar recommendations or author profiles. In actual development, labels should be combined and other, avoid excessive nesting, keep the structure simple, and verify the rationality of the structure through developer tools.

When you encounter the prompt "This operation requires escalation of permissions", it means that you need administrator permissions to continue. Solutions include: 1. Right-click the "Run as Administrator" program or set the shortcut to always run as an administrator; 2. Check whether the current account is an administrator account, if not, switch or request administrator assistance; 3. Use administrator permissions to open a command prompt or PowerShell to execute relevant commands; 4. Bypass the restrictions by obtaining file ownership or modifying the registry when necessary, but such operations need to be cautious and fully understand the risks. Confirm permission identity and try the above methods usually solve the problem.

There are three main differences between Callable and Runnable in Java. First, the callable method can return the result, suitable for tasks that need to return values, such as Callable; while the run() method of Runnable has no return value, suitable for tasks that do not need to return, such as logging. Second, Callable allows to throw checked exceptions to facilitate error transmission; while Runnable must handle exceptions internally. Third, Runnable can be directly passed to Thread or ExecutorService, while Callable can only be submitted to ExecutorService and returns the Future object to

Javaprovidesmultiplesynchronizationtoolsforthreadsafety.1.synchronizedblocksensuremutualexclusionbylockingmethodsorspecificcodesections.2.ReentrantLockoffersadvancedcontrol,includingtryLockandfairnesspolicies.3.Conditionvariablesallowthreadstowaitfor

Java's class loading mechanism is implemented through ClassLoader, and its core workflow is divided into three stages: loading, linking and initialization. During the loading phase, ClassLoader dynamically reads the bytecode of the class and creates Class objects; links include verifying the correctness of the class, allocating memory to static variables, and parsing symbol references; initialization performs static code blocks and static variable assignments. Class loading adopts the parent delegation model, and prioritizes the parent class loader to find classes, and try Bootstrap, Extension, and ApplicationClassLoader in turn to ensure that the core class library is safe and avoids duplicate loading. Developers can customize ClassLoader, such as URLClassL

The key to Java exception handling is to distinguish between checked and unchecked exceptions and use try-catch, finally and logging reasonably. 1. Checked exceptions such as IOException need to be forced to handle, which is suitable for expected external problems; 2. Unchecked exceptions such as NullPointerException are usually caused by program logic errors and are runtime errors; 3. When catching exceptions, they should be specific and clear to avoid general capture of Exception; 4. It is recommended to use try-with-resources to automatically close resources to reduce manual cleaning of code; 5. In exception handling, detailed information should be recorded in combination with log frameworks to facilitate later

Java supports asynchronous programming including the use of CompletableFuture, responsive streams (such as ProjectReactor), and virtual threads in Java19. 1.CompletableFuture improves code readability and maintenance through chain calls, and supports task orchestration and exception handling; 2. ProjectReactor provides Mono and Flux types to implement responsive programming, with backpressure mechanism and rich operators; 3. Virtual threads reduce concurrency costs, are suitable for I/O-intensive tasks, and are lighter and easier to expand than traditional platform threads. Each method has applicable scenarios, and appropriate tools should be selected according to your needs and mixed models should be avoided to maintain simplicity

Static keywords are used in Java to create variables and methods that belong to the class itself, rather than instances of the class. 1. Static variables are shared by instances of all classes and are suitable for storing data shared by all objects, such as schoolName in the Student class. 2. Static methods belong to classes and do not depend on objects. They are often used in tool functions, such as Math.sqrt(), and can only access other static members. 3. Static code blocks are used to perform initialization operations when class loading, such as loading libraries or setting logs. 4. Static inner classes can be instantiated independently of the external class, but non-static members of the external class cannot be accessed. Rational use of static can effectively manage class-level resources and behaviors.
