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POHow can I avoid calling System.load twice?
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  1. POHow can I avoid calling System.load twice?
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    copied!<p>I have a class that calls a native function to get information about a system from its CMOS. The class has a static initialization block which loads the library containing the native function, and it looks something like this:</p> <pre><code>package lib.sysid; public class SysId { private static native int getSysIdNative(); private static final String SYS_ID_PATH = "libsysid.so"; static { System.load(SYS_ID_PATH); } public static int getSysIdFromCMOS() { int returnValue = getSysIdNative(); } } </code></pre> <p>According to my testing, the method works fine the first time I use it, but if I call the method again at a later time, the static initialization block also runs, causing an UnsatisfiedLinkError:</p> <pre><code>java.lang.UnsatisfiedLinkError: Native Library libsysid.so already loaded in another classloader </code></pre> <p>How can I avoid the static initialization block from executing the <code>System.load()</code> method if it has already been run?</p> <p>Alternatively, is there a way for me to attempt to "unload" the library if it is already loaded before calling the <code>System.load()</code> method again?</p> <p>EDIT: Strangely enough, if I surround the <code>System.load()</code> call with a try-catch block, I still get an UnsatisfiedLinkError, but this time it comes from the actual call to <code>getSysIdNative()</code>. The error I see is the following: </p> <pre><code>lib.sysid.SysId.getSysIdNative()I </code></pre> <p>What the heck is that "I" that shows up? I've tried to attach a debugger to this code to see where the message gets populated, but so far I haven't been successful.</p>
 

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