StringIndexOutOfBoundsException String index out of range: 0
The problem occurs when line is empty (e.g. “”). Then it doesn’t have a character at index 0, hence your error. To fix, you can check the length of line before you use charAt:
Java
ReferenceError: “alert” is not defined
alert is not part of JavaScript, it’s part of the window object provided by web browsers. So it doesn’t exist in the context you’re trying to use it in. (This is also true of setInterval, setTimeout, and other timer-related stuff, FYI.) If you just want to do simple console output, Rhino provides a print function to your script, so you could replace alert with print. … Read more
Implementing an actionlistener to a JTextField
From what you’ve provided, it looks like you’ve imported or implemented a class other than java.awt.event.ActionListener named, ActionListener (class name conflict). Try qualifying the parameter as java.awt.event.ActionListener:
Java Copy Constructor ArrayLists
Note: Cloning the lists, isn’t the same as cloning the elements in the list. None of these approaches work the way you want them to: The approaches above will fill people such that it contains the same elements as other.people. However, you don’t want it to contain the same elements. You want to fill it with clones of … Read more
The import javafx cannot be resolved
According to the packages list in Ubuntu Vivid there is a package named openjfx. This should be a candidate for what you’re looking for: JavaFX/OpenJFX 8 – Rich client application platform for Java You can install it via: It provides the following JAR files to the OpenJDK installation on Ubuntu systems: Hope this helps.
Why doesn’t RecyclerView have onItemClickListener()?
tl;dr 2016 Use RxJava and a PublishSubject to expose an Observable for the clicks. Original Post: Since the introduction of ListView, onItemClickListener has been problematic. The moment you have a click listener for any of the internal elements the callback would not be triggered but it wasn’t notified or well documented (if at all) so … Read more
Java read file and store text in an array
Stored as strings: For floats:
How to return a boolean method in java?
You’re allowed to have more than one return statement, so it’s legal to write It’s also unnecessary to compare boolean values to true or false, so you can write Edit: Sometimes you can’t return early because there’s more work to be done. In that case you can declare a boolean variable and set it appropriately … Read more
How to make a countdown timer in Java
Try this.
Java Array Sort descending?
You could use this to sort all kind of Objects Arrays.sort() cannot be used directly to sort primitive arrays in descending order. If you try to call the Arrays.sort() method by passing reverse Comparator defined by Collections.reverseOrder() , it will throw the error no suitable method found for sort(int[],comparator) That will work fine with ‘Array of Objects’ such as Integer … Read more