I’m trying to create a .jar file using the mac terminal but am having bit of trouble. I followed the steps here but was unsuccessful. I got this error message: So how exactly do you go about doing it? My java program is called Main.java and I have compiled it into a .class file. Now what do I do? Thanks
for-loop very slow on Android device
I just ran into an issue while trying to write an bitmap-manipulating algo for an android device. I have a 1680×128 pixel Bitmap and need to apply a filter on it. But this very simple code-piece actually took almost 15-20 seconds to run on my Android device (xperia ray with a 1Ghz processor). So I tried …
How to increase the slow scroll speed on a JScrollPane?
I am adding a JPanel in a JScrollPane in my project. All is working fine, but there is one problem about mouse scroll using the mouse-Wheel in JPanel. It’s speed is very slow on scrolling. How to make it faster? My code is : Answer You can set your scrolling speed with this line of code Here is details.
How to connect in java as SYS to Oracle?
I receive this error: How to fix? (I need to be SYS). Thanks. Answer try this :
Call and receive output from Python script in Java?
What’s the easiest way to execute a Python script from Java, and receive the output of that script? I’ve looked for different libraries like Jepp or Jython, but most appear out of date. Another problem with the libraries is that I need to be able to easily include a library with the source code (t…
Passing annotation properties to meta-annotations
Say I have an annotation with a property: and I want to create a compound annotation with several meta-annotations, including the one that takes a property Is there a way that I can pass properties to the compound annotation to one of the meta annotations? Eg, something like this: that is equivalent to, but m…
Heap allocation and suitable hardware
For a C# .net 3.5 application which unavoidably creates a lot of data on the heap, in terms of hardware what would I be looking for in terms of memory? Would it just be the largest socket bus width? Or the “bandwidth” of the memory sticks? Or the actual frequency they run at? We have concluded the…
LinkedList: java.lang.OutOfMemoryError: Java heap space
I’m trying to make a graph implementation for an assignment, which has Graph(GraphImp) objects and Node(NodeImp) objects. Node objects contain a reference to their Graph, x & y co-ordinates and a name. The Graph object contains a linked list of its Nodes. The problem occurs when I try to add a Node …
When a subclass is instantiated, is only one object created?
Since many constructors also call the superclass constructor, it seems like one could think that both the subclass and the superclass are instantiated when a subclass is instantiated; i.e. more than one object is created. Is still just one object created? Thank you Answer Just one object, even if the super…
Radio Button value retrieval using servlets
I’m quite new to the process of web development, so I apoligise if this seems a really silly question. Basically, I’m creating a servlet whereby a user will answer ‘yes’ or ‘no’ to three 3 questions, and then submit the form. What I wish to do is to retrieve the value of ea…