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package org.eclipse.jetty.util.preventers;

import java.lang.reflect.Method;

GCThreadLeakPreventer
Prevents a call to sun.misc.GC.requestLatency pinning a webapp classloader
by calling it with a non-webapp classloader. The problem appears to be that
when this method is called, a daemon thread is created which takes the
context classloader. A known caller of this method is the RMI impl. See
http://stackoverflow.com/questions/6626680/does-java-garbage-collection-log-entry-full-gc-system-mean-some-class-called
This preventer will start the thread with the longest possible interval, although
subsequent calls can vary that. Recommend to only use this class if you're doing
RMI.
Inspired by Tomcat JreMemoryLeakPrevention.
/**
 * GCThreadLeakPreventer
 *
 * Prevents a call to sun.misc.GC.requestLatency pinning a webapp classloader
 * by calling it with a non-webapp classloader. The problem appears to be that
 * when this method is called, a daemon thread is created which takes the
 * context classloader. A known caller of this method is the RMI impl. See
 * http://stackoverflow.com/questions/6626680/does-java-garbage-collection-log-entry-full-gc-system-mean-some-class-called
 *
 * This preventer will start the thread with the longest possible interval, although
 * subsequent calls can vary that. Recommend to only use this class if you're doing
 * RMI.
 *
 * Inspired by Tomcat JreMemoryLeakPrevention.
 */
public class GCThreadLeakPreventer extends AbstractLeakPreventer
{

    
See Also:
prevent.prevent(ClassLoader)/**
     * @see org.eclipse.jetty.util.preventers.AbstractLeakPreventer#prevent(java.lang.ClassLoader)
     */
    @Override
    public void prevent(ClassLoader loader)
    {
        try
        {
            Class<?> clazz = Class.forName("sun.misc.GC");
            Method requestLatency = clazz.getMethod("requestLatency", new Class[]{long.class});
            requestLatency.invoke(null, (Long)(Long.MAX_VALUE - 1));
        }
        catch (ClassNotFoundException e)
        {
            LOG.ignore(e);
        }
        catch (Exception e)
        {
            LOG.warn(e);
        }
    }
}