In Eclipse, how can I find all usages of a function in a Java app? What is the shortcut for that? I tried with Ctrl+H to search by method, but it return me all methods with the same name. Answer You can find a menu entry in the context menu, when right clicking on the function. You can also press
Using contains on an ArrayList with integer arrays
I have an ArrayList<int[]>, and I add an array to it. Suppose I want to know if j contains an array that has {1,2} in it without using w, since I will be calling it from another class. So, I create a new array with {1,2} in it… …but this would return false even though w was added to the
Java convert Arraylist to float[]
How I can do that? I have an arraylist, with float elements. (Arraylist <Float>) it is not working. cannot cast from Object[] to float[] Answer Loop over it yourself. The nullcheck is mandatory to avoid NullPointerException because a Float (an object) can be null while a float (a primitive) cannot be nu…
Java: can you cast Class into a specific interface?
I’ve got a project I am working on and in this project I would like to include the ability for developers to include their own plugins without having to change the whole code. This is what I have …
How to read PDF files using Java? [closed]
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httpURLConnection: how long can a post argument be?
I’m currently using something like this: With this I manage to pass some data to my server. What I’m wondering now is how much can be sent this way? I want to be able to send some xml files (100-200 lines long) and would like to know if I can do this? Jason Answer The post body (it’s not usu…
Finding Number of Cores in Java
How can I find the number of cores available to my application from within Java code?
The difference between n++ VS ++n in Java
My Java teacher said it was better to use ++n instead of n++, I am not seeing the logic behind this. Does anyone know? Answer ++n increments the value and returns the new one. n++ increments the value and returns the old one. Thus, n++ requires extra storage, as it has to keep track of the old value so it
Why doesn’t java.io.File have a close method?
While java.io.RandomAccessFile does have a close() method java.io.File doesn’t. Why is that? Is the file closed automatically on finalization or something?
Can I change my Windows desktop wallpaper programmatically in Java/Groovy?
Is there a way I can use Java (or Groovy) to change my desktop wallpaper in Windows XP? I have a program that creates a new image every day (or whenever) and I would like a way to automatically update my desktop. I’ve seem some questions on this site about C++ or .NET, but I did not see anything specifi…