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Miscellaneous I<br />
use it.<br />
I want to keep my java GUI always on the top of any other desktop application.<br />
Any idea?<br />
I want to keep my java GUI always on the top of any other desktop application. Any<br />
idea?<br />
Answer: Spawn a thread that knows about the parent Window, and every X<br />
milliseconds, executes the toFront () command of that window. Just remember to<br />
execute it using SwingUtilities.invokeLater (), and don't<br />
let your users launch two apps, unless you enjoy screen lockup.<br />
Can a java application be run of a CD without installing anything (i.e. runtime, etc)<br />
on the target computer?<br />
I would like to put my application and hand it out as a demo, but I want to make it<br />
easy to view.<br />
Answer1: by Dale King The JRE was made so that it didn't need to be "installed".<br />
What I did in one case was to simply put the JRE into a jre folder in the same<br />
directory as my application then invoke it from that directory using:<br />
jre\bin\jre.exe -cp MyJar.java MyClass<br />
That was for JDK1.1 and you have to modify it slightly for <strong>Java</strong> 2. But this did not<br />
require any installation of environment variables to be set up. The JRE was smart<br />
enough to know how to get to its system classes relative to where the jre.exe file was<br />
located.<br />
Answer2: you could try a <strong>Java</strong> to native compiler.<br />
I would like to know whether it is possible to test the memory, so as to avoid the<br />
OutOfMemoryError or whether it is possible to increase the amount of memory in the<br />
JRM.<br />
Answer: You can get the total and available memory used by the VM by making two<br />
calls from the Runtime class:<br />
Runtime runtime = Runtime.getRuntime();<br />
long free = runtime.freeMemory(); //the available memory<br />
long total = runtime.totalMemory(); // the total for the JVM<br />
The amount returned be totalMemory() isn't that useful unless you specify how much<br />
memory your program will have from the beginning (if you don't, the JVM will just<br />
keep grabbing more until you run out).<br />
You can set the initial and maximum memory from the command line:<br />
java -Xms64m -Xmx64m name.of.Application<br />
This will start your appplication with 64 megs initial and maximum memory.<br />
--<br />
Corey Wineman<br />
What needs to be done to reduce size of a jar file? What optimization techniques<br />
to use on classes inside the jar file? What tools if any?<br />
Answer: A JAR file is a ZIP archive. You can influence its size by choosing the<br />
degree of compression you want to have. This is usually defined by a value between<br />
0 (no compression) and 9 (maximum compression). Although JAR tool does not list a<br />
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