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A Journey to the World of Android Wearable

by ridoy

A brief explanation of application development for Android Wear, helpful for every beginner and intermediate android developer.

Never Buy A Garage Door Remote Again: Open Your Door With Your Android Phone (via Bluetooth)

by raddevus

Steps for building a device you can add to your existing garage door, which implements an atmega328, bluetooth (hc-05) and relay module which will allow you to open your garage door from any paired Android device.

Android Programming By An Example: Creating An Airport Schedule Simulator Application

by Arthur V. Ratz

In this article, we will discuss about the advanced Android application development based on the example of creating a responsive Airport schedule simulator application.

Still Don’t Get the Difference of “Overloading and Overriding”?

by Afzaal Ahmad Zeeshan

This post attempts to describe the general difference between overloading and overriding in Object-oriented programming languages.

Latest Articles

Wrapping Java with C++ Objects - JNI OOP

by Yochai Timmer

A way to avoid JNI's reflection oriented programming. Wrapping Java with C++

Windows / Android (C#/Java) Compatible Data Encryption with Compression

by JudyL_MD

Code sample for passing encrypted compressed data between Windows and Android

An In-Depth Tutorial on Lucene and Java

by Han Bo Sun

This is a more in-depth tutorial on integrating Lucene search and index engine in Java applications.

Smallscript - A Smalltalk-Inspired Scripting Language

by Łukasz Bownik

Smallscript is a little scripting language inspired by Smalltalk syntax.

All Articles

Java

Problem to solve with the for structure

U 8 Apr 2024 by Patrice T

Advice: Learn to indent properly your code, it show its structure and it helps reading and understanding. It also helps spotting structures mistakes. Scanner sc = new Scanner(System.in); System.out.println("Ingrese un número"); numero =...

Problem to solve with the for structure

U 8 Apr 2024 by Nayeli Guitarra

Perform this exercise in Java language: Create a program in which you enter integers and calculate: to. the product of all even numbers less than 25 b. The sum of all odd numbers greater than 16 c. The average of all numbers multiples of 4 What...

Problem to solve with the for structure

N 8 Apr 2024 by OriginalGriff

Move the read of the number inside the for loop ... Two other things: 1) Read the question carefully: the first part requires even number, the second odd, but the third needs odd and even. There is no "third state"! 2) Pick an indentation...

How do i...code this

U 8 Apr 2024 by Pritong water

You are given a text file named sentences.txt, which contains a list of sentences separated by newline characters. Each sentence is composed of words separated by spaces. Your task is to read the sentences, reverse each sentence, and then output...

How do i...code this

N 8 Apr 2024 by Pete O'Hanlon

You have all the information you need in the assignment. We don't write the answer to assignments, as this won't benefit you. Take the question, and break it down. Work out what you, as a human, would do in small logical steps. If you get code...

Chats are not appearing on chatwindowactivity in andriod studio java using firebase

U 8 Apr 2024 by VortexV7

The chats/messages are not appearing on my app's chat windows but when I have checked my firebase database it is showing there properly. Here is the code please look into it. ChatWindow.java package com.vortexv.vconnect; import...

App crashing when login in to mainactivity in android studio java

U 6 Apr 2024 by Pete O'Hanlon

Add an empty default constructor to the class.public Users() {} The error told you exactly what the problem was.

App crashing when login in to mainactivity in android studio java

N 6 Apr 2024 by VortexV7

I am using firebase as my database for my app which is an chatting app. And my app is crashing whenever I try to login or sign up to my app main activity the app crashes automatically. MainActivity.java package com.vortexv.vconnect; import...

I really need help fixing my errors

N 4 Apr 2024 by Pete O'Hanlon

To add to the advice given here - you can actually test to see if your scanner has any more input to work with by using the hasNext(); method to determine whether the scanner has anything else to do or not.

I really need help fixing my errors

N 4 Apr 2024 by OriginalGriff

Start by looking at the error message closely - this will help: How to Write Code to Solve a Problem, A Beginner's Guide Part 2: Syntax Errors[^]. It's primarily about compilation errors while your problem is a runtime error, but the information...

I really need help fixing my errors

N 4 Apr 2024 by Graeme_Grant

This should help you identify the issue: How to Fix the No Such Element Exception in Java | Rollbar[^].

I really need help fixing my errors

U 4 Apr 2024 by Cindy Ann

import java.util.Scanner; public class MyCalculator { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); // userInput // i searched online how to restart a program with y/n ...

Basically we have taken an array where

1 Apr 2024 by Pete O'Hanlon

Let’s suppose that we help you with something that looks like homework. Suppose we came up with the solution for you. How do you think that would help you. Any code that we wrote would be our code, not yours, so you would be in a position where...

Basically we have taken an array where

1 Apr 2024 by OriginalGriff

While we are more than willing to help those that are stuck, that doesn't mean that we are here to do it all for you! We can't do all the work, you are either getting paid for this, or it's part of your grades and it wouldn't be at all fair for...

Shortest subarray with or at least K I

31 Mar 2024 by Patrice T

First error, but not the last: currOR ^= nums[left++]; '^' is the xor operator, you want to use '|' the or operator. Your code do not behave the way you expect, or you don't understand why ! There is an almost universal solution: Run your code...

Shortest subarray with or at least K I

30 Mar 2024 by OriginalGriff

Compiling does not mean your code is right! :laugh: Think of the development process as writing an email: compiling successfully means that you wrote the email in the right language - English, rather than German for example - not that the email...

Wrapping Java with C++ Objects - JNI OOP

27 Mar 2024 by Yochai Timmer

A way to avoid JNI's reflection oriented programming. Wrapping Java with C++

I am trying to make a java application run in eclipse with the following criteria below.

21 Mar 2024 by OriginalGriff

This is one of the most common problems we get asked, and it's also the one we are least equipped to answer, but you are most equipped to answer yourself. Let me just explain what the error means: You have tried to use a variable, property, or a...

Can't get springmvc to create table in mysql database

21 Mar 2024 by UT7

I've resolved this issue, start.spring.io created a package for the main class where the SpringApplication.run method is and I created my other packages on the same level as the package where the main class was instead of creating them directly...

I am trying to make a java application run in eclipse with the following criteria below.

21 Mar 2024 by Jordan Schwartz 2024

Using the source code given, update the simple list to your top five chosen destinations. Include the destination title, a short description, and a small image for each. This will help ensure that you have fulfilled the acceptance criteria of the...

Maven JPA integration: processor not found

19 Mar 2024 by Pete O'Hanlon

The beauty of annotation processing is that it doesn't require you to explicitly pick a type in the @SupportedAnnotationTypes. Change that line to @SupportedAnnotationTypes("*") and this should pick up any annotations that you have in the project.

How to copy list and import as it is in postgresql database in fraction of a second

19 Mar 2024 by Pete O'Hanlon

Without knowing where you were sourcing your data, this is an almost impossible question to answer. There are a few things that do occur from looking at this. You are adding a random UUID but that could easily be auto-generated by the database....

How to copy list and import as it is in postgresql database in fraction of a second

19 Mar 2024 by OriginalGriff

Nobody can guarantee you "a fraction of a second" to add a million rows to a DB, PostgreSQL or not - it will depend on far too many factors: the computer(s) that the DB engine is running on, the activity level on the DB, the connection between...

How to copy list and import as it is in postgresql database in fraction of a second

18 Mar 2024 by Office Systems

I'm having an array list which has more than 1 million of records in it, I want to dump it as the way it is in PostgreSQL database using something built in methods like Copy-manger or any method which will be more faster to import this large...

How do I uninstall m2e-wtp-maven integration for WTP from eclisple IDE

18 Mar 2024 by Tyler Bakeman

In Eclipse Marketplace (which you can access through the Help button in Eclipse), it shows your plugins (some of them, not all of them), such as M2E. When I switched M2E, to an alternate in Eclipse, it gave me the option to “change”/“disable”...

Reduce complexity of printaquarium method

18 Mar 2024 by Tyler Bakeman

I hope this message helps you to continue. Before I tackle the moveFishes method, as well as some of the other methods (changeDirection, turnFish, etc), I think we should take a look at how we store all of the fish themselves: Your fish are...

Internal storage video downloder

18 Mar 2024 by Aftab Amjad

Hi, I am trying to download a video from url and save it in the internal app storage which can be viewed in the Downloaded Fragment. The problem is that when i click the download button video starts downloading and in notification bar downloading...

Maven JPA integration: processor not found

15 Mar 2024 by Tyler Bakeman

Personal Project: I am new to Maven and have spent a few weeks troubleshooting pom errors with chatGPT. Tutorials are hard to come by online, because annotation-processing in Java is more complicated than the sources I've found. Issue in summary:...

Java spring file upload using webclient

15 Mar 2024 by joaoandreav

Looks like the file path might be wrong, or the resource handling needs work. Also, ditch .block() and handle things asynchronously. Double-check the file path and make sure it points to the actual file. Verify your resource and check server logs...

How to start other services from one service in microservices using spring boot

14 Mar 2024 by Pete O'Hanlon

Assuming that these are separately deployed services, I wouldn't attempt to start them from a central location. What I do is deploy my services in separate containers (Kubernetes on my part, but you could use Docker), and use orchestration to...

How to start other services from one service in microservices using spring boot

14 Mar 2024 by Office Systems

I'm having different micro-services such as configuration service, service registry, order service, customer service, payment service, front-end service, these services they fetch their configurations from config server and they are all connected...

Windows / Android (C#/Java) Compatible Data Encryption with Compression

13 Mar 2024 by JudyL_MD

Code sample for passing encrypted compressed data between Windows and Android

How can I loop and compare the data present between two arrays in spring boot

10 Mar 2024 by Pete O'Hanlon

As I don't know what Order looks like, I'm going to make some assumptions in this answer. The big assumption I'm going to make is that you have an Integer id value in the class, which I can get using getId();. I'm also going to assume that the...

How can I loop and compare the data present between two arrays in spring boot

10 Mar 2024 by Office Systems

I have two arrays which both have data, what I want to do is to loop through each array and compare the data between the arrays one array is coming from the Post Method and another array has data from the database, so the comparison has to be...

An In-Depth Tutorial on Lucene and Java

8 Mar 2024 by Han Bo Sun

This is a more in-depth tutorial on integrating Lucene search and index engine in Java applications.

Can't get springmvc to create table in mysql database

27 Feb 2024 by UT7

Hello everyone, please I can't get SpringMVC project to create a table in MySql database. My entity class is below. @Entity @Table(name="customer") @Data @NoArgsConstructor public class Customer { @Id @GeneratedValue(strategy =...

How to use hystrix dependency with spring boot version 3.2.2

27 Feb 2024 by Office Systems

I have created a spring boot application of version 3.2.2 which is going to act as a gateway service, the challenge I'm facing at the moment is that whenever I try to add hystrix dependencies for monitoring and for dashboard visualization of up...

What am I missing? I have tried so many ways to solve this.

21 Feb 2024 by Caroldoria Harris

The cost to ship a package is a flat fee of 75 cents plus 25 cents per pound. 1. Declare a constant named CENTS_PER_POUND and initialize with 25. 2. Get the shipping weight from user input storing the weight into shipWeightPounds. 3. Using...

What am I missing? I have tried so many ways to solve this.

20 Feb 2024 by Patrice T

Quote: What am I missing? I have tried so many ways to solve this. Not your problem, but: All these int shipCostCents = 0; final int FLAT_FEE_CENTS = 75; final double CENTS_PER_POUND = 25; are cents. Why are you mixing data...

What am I missing? I have tried so many ways to solve this.

20 Feb 2024 by CPallini

Replace Quote: final double CENTS_PER_POUND = 25; shipWeightPounds = scnr.nextDouble(); with final int CENTS_PER_POUND = 25; shipWeightPounds = scnr.nextInt();

Java spring file upload using webclient

19 Feb 2024 by developer new 2024

Hello, need help in solving an issue in code while uploading a file using webclient in Java as i keep getting errors. The code I tried: The code I tried returns error 'end of file never reached'. I have tried several solutions like converting...

How do I solve an orphaned case error type

16 Feb 2024 by OriginalGriff

We can't answer that based on a single line of code in isolation. Best guess? A spurious (or missing) close curly bracket. Start with the whole error message, and it will tell you where to begin looking. This should help you understand what the...

How do I solve an orphaned case error type

16 Feb 2024 by Munashe Gladson

orphaned case case 4: What I have tried: orphaned case case 4:

Java text editor project to improve my skills

10 Feb 2024 by M-Badger

Google and ChatGPT/Bing Copilot are your friend. Google Java Swing | Create a simple text editor - GeeksforGeeks[^] Build your own text editor in Java | Opensource.com[^] java-text-editor · GitHub Topics · GitHub[^] Bing Copilot Sure, I'd be...

Java text editor project to improve my skills

10 Feb 2024 by OriginalGriff

We can't answer this specifically: we have no idea of your skills, abilities, experience, or the environment in which the app should run - and how and where you start will depend on all those things. So all we can do is give generic advice: How...

Java text editor project to improve my skills

10 Feb 2024 by Samar Khan 2024

I want to create a simple text editor using Java. I would also like to implement some features like auto completion and syntax highlighting. Any help is appreciated. What I have tried: I have not tried anything at all. I need some guidance

How do I actually build projects using java

31 Jan 2024 by Richard MacCutchan

Take a look at Java Tutorials Learning Paths[^] and Welcome to Apache NetBeans[^]. Lots of useful tutorials and ideas, but also guidance on how to put things together.

How do I actually build projects using java

31 Jan 2024 by OriginalGriff

We really can't tell you anything specific - it's a skill, and the only way to build a skill is through practice - you can watch as much of the Tour de France as you like, but it isn't going to teach you to ride a bicycle! :D Pick a subject that...

How do I actually build projects using java

30 Jan 2024 by Srihari Vernekar

Hello there, i am facing a problem of not being able to build any useful projects. I have worked on learning concepts of OOP and also other basic concepts of programming and i have very well understood the concepts, but still lacks behind in...

Implement a function called countcharacters, which counts the number of chara cters in a string.

21 Jan 2024 by Mike-MadBadger

The question tags java/javascript but your question includes a pointer (*str), I am therefore assuming that it is in fact C code. The answer would be different in java/javascript but the principle would be the same. You're not going to get...

Implement a function called countcharacters, which counts the number of chara cters in a string.

21 Jan 2024 by OriginalGriff

While we are more than willing to help those that are stuck, that doesn't mean that we are here to do it all for you! We can't do all the work, you are either getting paid for this, or it's part of your grades and it wouldn't be at all fair for...

Spring cloud config client unable to load configurations from spring cloud config server in spring boot

19 Jan 2024 by Office Systems

I have created Spring cloud config server to include all configurations of spring cloud config clients for my application, the problem is that my spring cloud config clients can not obtain the configurations from the spring cloud config server...

Deployed angular and spring boot projects on azure not working as expected

18 Jan 2024 by Pete O'Hanlon

The problem isn't in your code, rather the problem is with your deployment. You have stated that you deployed your application to Azure, and this brings its own set of expectations. Basically, the CORS request is being blocked by Azure, not by...

How do i...scale weight display

17 Jan 2024 by Bernardo Martinez

Hi I am a Digital weight scale yp200 braunker received from the RS232 port sends. Now I want to get this information in my application I want to display. The source does not anyone do this? C # language using the Serial port What I have tried: ...

Implementing data upload and read microservices project

17 Jan 2024 by Office Systems

I'm new to Micro-services architecture, I'm to develop a project using spring boot that gets data from API and stores that data into PostgreSQL db then computes and gets the sum of the data uploaded and sends that data into another database...

How do i...scale weight display

16 Jan 2024 by CPallini

You can also download the (Spanish) manual of the device, wherein the serial protocol is concisely described.

How do i...scale weight display

16 Jan 2024 by Graeme_Grant

You need to do research via Google Search. To get you started, here is the question I asked it: c# example of reading values from the Digital weight scale yp200 braunker[^] ... there are a few results Here is a helpful answer, but not for that...

Log4j is not working with my selenium automation project

14 Jan 2024 by Member 15226818

I wrote a sample code to work with the log4j library, but I encountered an error as mentioned below. Additionally, a new log4j file isn't being created. Can anyone help me understand why this error is occurring? What I have tried: This is my...

How to show and hide password by click on eye in ASP.NET C#

9 Jan 2024 by Member 16179780

👁 function togglePassword(obj) { ...

SOAP/XML signautre verification failed for strtransform - javax.xml.crypto.marshalexception

3 Jan 2024 by mickohan

Friends, I am able to unmarshall signature block for most of the cases with below code. However its failing to unmarshall for STRTransform case. Can someone guide me? Exception: Exception in thread "main" javax.xml.crypto.MarshalException:...

Smallscript - A Smalltalk-Inspired Scripting Language

3 Jan 2024 by Łukasz Bownik

Smallscript is a little scripting language inspired by Smalltalk syntax.

Spring-cloud-client not able to get configurations from config-server

2 Jan 2024 by Office Systems

I'm trying to create Micro-services architecture using spring boot, the only challenge I'm facing at the moment is how to configure spring cloud client to pull all the configurations from the config server, the config server gets all the...

How do I transfer the user from one jframe to another jframe?

29 Dec 2023 by Andre Oosthuizen

In Java, you can do something similar by using the 'CardLayout' for switching between different panels using Java Swing method. Example code - import javax.swing.*; import java.awt.*; import java.awt.event.ActionEvent; import...

How do I transfer the user from one jframe to another jframe?

28 Dec 2023 by NoName900

i'm coding a little java gui register project for practice. I've built the register Jframe and i want to move to a login Jframe by pressing a button. my question is, i remember in C# asp.net for example if you want to move to another page you...

How do I do GUI in java to add information of users

24 Dec 2023 by Richard MacCutchan

See the Java Tutorials Learning Paths[^]

How do I do GUI in java to add information of users

24 Dec 2023 by OriginalGriff

While we are more than willing to help those that are stuck, that doesn't mean that we are here to do it all for you! We can't do all the work, you are either getting paid for this, or it's part of your grades and it wouldn't be at all fair for...

How do I do GUI in java to add information of users

24 Dec 2023 by Shahdoda

Do a project GUI in java that allows the user to add ,edit,delete information from table .the information is name,phone,email,address,gender, age,relationship and add validation Drag and drop What I have tried: Drag and drop...

A method to handle collisions in a fish tank class, to provide fish from dissapearing

24 Dec 2023 by Gerry Schmitz

With your design, you can't handle "collisions", because you're using "buckets". You can only "avoid" collisions by checking the bucket you "plan" to move to by first checking the bucket to see if it is "empty". You could wind up with a...

A method to handle collisions in a fish tank class, to provide fish from dissapearing

23 Dec 2023 by fs7schmitzii

This is a Fish Tank, where certain variants of fish can "swim" in. They move horizontal and vertikal (the vertikal movement is random). But one aspect is not covered yet. When two fish collide one fish just dissapears and never gets shown again....

Com.jgoodies.looks does not exist

23 Dec 2023 by Vishal Virmani India

packages com.jgoodies.looks does not exist .How to rectify this error in net beans .I am not able correct this even after downloading jgoodies.looks jar file and even after adding it to library .Can u plz correct this error What I have tried: ...

Reduce complexity of printaquarium method

22 Dec 2023 by fs7schmitzii

I built a virtual aquarium. The problem on the one side is, that my moveFishes() method is really complex structured to the point, where I personally don't know how to structure it into different methods, while justifying, the program is still...

How do I make string.indexof() stop at the end string.length() in a for loop in java

17 Dec 2023 by Dave Kreskowiak

This is where running the code under the debugger and stepping through the code line by line and inspecting variables would have helped you solve this faster than you could have typed the question into CodeProject. The problem is not about...

How do I make string.indexof() stop at the end string.length() in a for loop in java

17 Dec 2023 by UT7

Hello everyone, I am using String.indexOf() to find all occurrences of a character in a string using a for loop. The problem is, I taught that if I iterate over the string in a for loop till the end of the length of the string the iteration...

CaptureManager SDK - Capturing, Recording and Streaming Video and Audio from Web-Cams

17 Dec 2023 by Evgeny Pereguda

This article presents my project for capturing of video and audio sources on Windows OS by Microsoft Media Foundation.

Null-Safety in the Practical Type System (PTS)

14 Dec 2023 by ChristianNeumanns

The "absence of a value" is among the most important concepts a type system has to deal with.

What is an instance variable ?

12 Dec 2023 by M Imran Ansari

Instance variables are declared/defined in a class but outside the constructor (s), method(s) and block(s). For memory management, when memory is allocated for an object in a heap, a slot for each of the instance variables is created. Further,...

What is an instance variable ?

11 Dec 2023 by CPallini

See, for instance: Difference between Instance Variable and Class Variable - GeeksforGeeks[^].

What is an instance variable ?

11 Dec 2023 by Member 16128751

Attributes or Properties: Instance variables represent the attributes or properties of an object. For example, if you have a class representing a "Car," instance variables might include attributes like "color," "model," or "year." Scope: The...

What is an instance variable ?

11 Dec 2023 by Member 16161055

Memory Overhead : Each instance of a class with its set of instance variables consumes memory. If there are many instances with large sets of variables, it can lead to increased memory usage What I have tried: An instance variable is a variable...

Running Automation Tests At Scale Using Appium

11 Dec 2023 by Suhagkumar Vamja

The article discusses the challenges faced by businesses in releasing mobile applications quickly and the importance of faster time to market (TTM)

Union Types in the Practical Type System (PTS)

30 Nov 2023 by ChristianNeumanns

Union types (aka sum types, variants, choice types) provide an elegant solution for frequent programming tasks.

How do I regex a string that contains forward slases

27 Nov 2023 by Pam04

getReplacementMap().put("regex...

How do i... [Do my homework]

25 Nov 2023 by Richard MacCutchan

No, we will not do your homework for you. It is your assignment to test your learning, not your ability to cheat.

How do I regex a string that contains forward slases

25 Nov 2023 by Patrice T

Quote: How do I regex a string that contains forward slases The problem is not necessarily where you think it is. Use tools to see what part of RegEx matches what part of string, you may find surprises. Just a few interesting links to help...

How do I regex a string that contains forward slases

24 Nov 2023 by Andre Oosthuizen

You can achieve your goal by simplifying it all - Remove unnecessary angle brackets, simplify the character class for your directory and file name, still included the dot '.' in the character class for your file extension -...

How do I regex a string that contains forward slases

24 Nov 2023 by Pam04

Hello, I have a file hashname path generated in my tests as below. It has '/' for directory path, underscore and hyphens in random positions in file name. I want to replace this entire path using regular expression in my JPO. What I have tried: ...

How do I regex a string that contains forward slases

24 Nov 2023 by Manish Kumar 2021

Can you try this getReplacementMap().put("regex:[^/]+/[a-zA-Z0-9_-]+[_-]+[a-zA-Z0-9_-]+[^.]+\\.[a-zA-Z0-9]+", "");

How do I regex a string that contains forward slases

22 Nov 2023 by M Imran Ansari

Check this solution. Find a string using regex with forward slashes in it[^] Further, you can use this link to generate and test your regular expression. RegExr: Learn, Build, & Test RegEx[^]

Running Automation Tests At Scale Using Playwright

22 Nov 2023 by Suhagkumar Vamja

In this article, we learn about Playwright, how it works, and why it is a good choice for web automation with Java.

How do I uninstall m2e-wtp-maven integration for WTP from eclisple IDE

21 Nov 2023 by UT7

Hello everyone, please I was trying to create a Spring boot project from eclipse IDE and I got this error - 'Import Getting Started Content' has encounter a problem. NoSuchMethodError: 'void ...

How to share the project file here ?

16 Nov 2023 by Dave Kreskowiak

You don't. The site does not allow uploading projects. That would take a lot of disk space and can easily be abused by those who are not trusted. You have to paste the code snippets relevant to the problem, not the entire file(s).

How to share the project file here ?

16 Nov 2023 by Krish The Great

Being a beginner,I am having a lot of problems(errors and exceptions) in my java project. How do I share the project here(the files)? What I have tried: I am a beginner is Java oops programming and not able to figure out few problems in my...

Record Types in the Practical Type System (PTS)

12 Nov 2023 by ChristianNeumanns

This article explains why we need native record types, and how they work in PTS.

Can someone explain to me why line 4 is error?

12 Nov 2023 by Andre Oosthuizen

You have not initialized the 'next' node in your constructor, you can set the 'next' to null. This way, when you create a new 'ListNode', the 'next' field is set to null by default - class ListNode { int data; ListNode next; public...