Tag: arrays

Checking to see if a 2d array is jagged

arrays jagged-arrays java multidimensional-array

I am finishing up a program but having a bit of trouble with one last aspect. In this part of the program, I am testing to see if the array is jagged (same number of rows and columns). I want to use a nested for loop to do this but am having trouble with the logic and structure. For example,

How to convert JSONObjects to JSONArray?

arrays java json

I have a response like this: Here is my code: How do I convert “songs” to a JSONArray? Answer Something like this:

How to trim out an array of integers in Java?

arrays java

Let’s that I have a number N. N will be the size of the array. However, the contents of the array will hold every other number from 1 to positive N. This means that the entire size N array will not be full after that for loop. So after the for loop, I want to trim (or resize) the array

Calculate average of a huge long array

arrays java numbers performance

I’m trying to calculate the average of many (more than 200) long (primitive type) values stored in an array. Usually you add all the numbers and divide it by the number of the values. But this is not possible in this case since there is no primitive datatype in Java capable of holding such a large number, isn’t it? Will

Setting all values in a boolean array to true

arrays boolean java variables

Is there a method in Java for setting all values in a boolean array to true? Obviously I could do this with a for loop, but if I have (for example) a large 3D array, I imagine using a loop would be quite inefficient. Is there any method in Java to set all values in a certain array to true,

How can I shuffle the letters of a word?

arrays java random

What is the easiest way to shuffle the letters of a word which is in an array? I have some words in an array and I choose randomly a word but I also want to shuffle the letters of it. I am not supposed to use that List thing. I’ve come up with something like this but with this code

Java Array of unique randomly generated integers

arrays java

I have a method above which should generate an array of random elements that the user specifies. The randomly generated integers should be between 0 and 10 inclusive. I am able to generate random integers but the problem I have is checking for uniqueness. My attempt to check for uniqueness is in my code above but the array still contains

Java read file and store text in an array

arrays file-io java storing-data

I know how to read a file with Java using Scanner and File IOException, but the only thing I don’t know is how to store the text in the files as an array. Here is a snippet of my code: Here is what my KeyWestTemp.txt file contains: Answer Stored as strings: For floats:

Alternating between even and odd elements in Array with GUI

arrays java jpanel swing user-interface

I’m trying to work with more GUI stuff but I’m having problem with something. I have an array of JLabels. Each of them contain 1 number from 0 to 7. I’m making the numbers “light up” by changing …

Saving byte array using SharedPreferences

android arrays java sharedpreferences

So I have a byte [] array which I have created in my android app. I want to use SharedPreferences from android to store it and retrieve it back again when I start my app. How can I do that ? Answer You could try to save it has a String: Storing the array: Retrieving the array: