System Engineer/Software Engineer

Christopher Schene

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CEHj thanks.<br><br>Will my idea of using an abstract class work where I'll extend the GUI class and another class that mimics it, to keep the program flow normal. When program is headless I'll construct a class that mimics some of the GUI program flow without actually creating any GUI classes and when not headless, I'll construct the GUI class.<br><br>I have done runtime binding in C++, C Sharp but never tried it in java. <br><br>I am going to try this approach: using a class with abstract methods where when headed, the commands go to the GUI interface and when headless, they go to the headless version.
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Yes that sounds good. Go for my second suggestion as that will retain cross-platform ops
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It looks like your "isHeadless: suggestion will work well for my code. Almost done.
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This is the code I added. Eclipse seems to like it.<br><strong>public</strong> <strong>void</strong> log(String s) {<br>&nbsp; &nbsp; &nbsp; <strong>if</strong>(GraphicsEnvironment.<em>isHeadless</em>() == <strong>true</strong>) {<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;//do nothing (add log to a file later)<br>&nbsp; &nbsp; &nbsp; } <strong>else</strong> {<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;System.<strong><em>out</em></strong>.println(s);<br>&nbsp; &nbsp; &nbsp; }<br>&nbsp; &nbsp;}<br><br><br>
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It turns out I don't really need the abstract class, but I did use your headless check.<br><br>I'll give credit for that.<br><br>I am going to ask another question about appending to a file (my code doesn't append but creates a new file each time): Easy credit for my file output question coming up.
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:) Too late for the new one - answered ;)
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I am working on a program written in Java that is currently running and interacting graphically with the users and I want to add a "headless" option so that at runtime I will bind either to the class. that handles the GUI and when I am running headless, I will replace that GUI class with a replacement class where the GUI calls are stubbed out.<br><br>The reason I am doing this is that when I tried to run "headless" using crontab. crontab would not run the program emailed me an error message indicating &nbsp;the program required a display.<br><br>I have heard I can do runtime binding &nbsp;in Java using an abstract class, but I am asking for help to do that.
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I am working on a program written in Java that is currently running and interacting graphically with the users and I want to add a "headless" option so that at runtime I will bind either to the class. that handles the GUI and when I am running headless, I will replace that GUI class with a replacement class where the GUI calls are stubbed out.
The reason I am doing this is that when I tried to run "headless" using crontab. crontab would not run the program emailed me an error message indicating  the program required a display.
I have heard I can do runtime binding  in Java using an abstract class, but I am asking for help to do that.

How do I implement runtime class binding in Java

runtime

Java is a platform-independent, object-oriented programming language and run-time environment, designed to have as few implementation dependencies as possible such that developers can write one set of code across all platforms using libraries. Most devices will not run Java natively, and require a run-time component to be installed in order to execute a Java program.