Why “non-static variable cannot be referenced from a static context” produced for one program but not another? [duplicate] solved Why “non-static variable cannot be referenced from a static context” produced for one program but not another? [duplicate]
Introduction When programming in Java, it is important to understand the concept of static and non-static variables. This is because the compiler will throw an error if a non-static variable is referenced from a static context. This error can be confusing, as it may appear in one program but not another. In this article, we … Read more
Once compiled, kotlin bytecode is identical to java bytecode. Any application that uses compiled programs/addons for the JVM will work with java, kotlin, and any other JVM language. solved Code addon with kotlin and convert the code to java
Introduction When writing code in an object-oriented language, it is important to understand the concept of access modifiers. Access modifiers are used to control the visibility of class members, such as methods, variables, and constructors. One of the access modifiers is the protected modifier, which allows a class to access its own members, but not … Read more
You are creating local variables of button1, button2 etc inside the onCreate method. This way, the generateQuestion method is unaware of these variables and uses the class variables with the same name (not included in your code, but I imagine you have somewhere declared them probably on top of your activity class) which are not … Read more
Declare the ed_text and mViewPager in your onCreate like this final EditText ed_text =(EditText)findViewById(R.id.editText1); final ExtendedViewPager mViewPager = (ExtendedViewPager) findViewById(R.id.view_pager); and now you can access the ed_text value in the bt_Goto click listener like this bt_Goto.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { if(ed_text.getText().toString().length() > 0){ mViewPager.setCurrentItem(Integer.parseInt( ed_text.getText().toString())); } } }); 1 solved Get … Read more
I recommend just making a list of doubles. I don’t know if what you want to do is possible in Java. Like so: List<Double> dubs = new ArrayList<>(); while (in.hasNextLine) { dubs.add((double) in.next()); } 1 solved Is there a way to generate ints using i?
As @AndyTurner said in a comment: fields[1] is a String, not a HashSet<String>. You can build the latter using new HashSet<>(Arrays.asList(fields[1])). But there are other issues with this snippet too. It would be better to rewrite like this, pay close attention to every little detail that I changed: private Map<String, Set<String>> userBusiness = new HashMap<>(); … Read more
What you are trying to do does not make much sense. You cannot change something that is a type String to a class object. Either you need to change what is being passed to the constructor or you need to change the type of the instance variables to String. Personally I would change the Node … Read more
Say you have two people Max and Simon. You could do something like below where you first find the amount owed by Max using your logic. And then to find the amount owed by Simon you just use totalCost – amountMaxOwes: import java.util.Scanner; class Trip { public static void main(String[] args) { Scanner scanner = … Read more
You’re not instantiating a Number. You’re instantiating a Number[]. These are two completely different objects. You can generally expect to be able to instantiate an array of any type, even types that you can’t directly instantiate yourself. You can populate these arrays through type inheritance and the is-a relationship. For example, with the above, you … Read more
Introduction If you are looking for help with printing a string in a maximum of three lines and with a width parameter, then you have come to the right place. In this introduction, we will discuss the basics of printing a string in a maximum of three lines and with a width parameter. We will … Read more
package com.TnationChallange; import java.util.ArrayList; import java.util.List; public class Main { public static void main(String[] args) { for (String part : getParts(“limited screen space to display information”, 7, 3)) { System.out.println(part); } } private static List<String> getParts(String string, int partitionSize, int maxLine) { List<String> parts = new ArrayList<String>(); int len = string.length(); for (int i = … Read more
I have some trouble understanding your English, so I might have misinterpreted some of your questions. What do you call this object in Java and why do you use? I don’t know which “object” you are referring to. … yet still don’t know why is this possible and what this is called. It is just … Read more
In my opinion, you forget to press “Enter” after entering input. A scanner can read the input if only you press the “Enter” key. Your solution seems correct to me. I was able to properly run it on my PC. You can find a similar question here: How to use Scanner to accept only valid … Read more