com.sun.tracing.Probe Maven / Gradle / Ivy
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package com.sun.tracing;
/**
* The {@code Probe} interface represents a tracepoint.
*
* A {@code Probe} instance is obtained by calling the
* {@code Provider.getProbe()} method of a provider instance created by
* {@code ProviderFactory.createProvider()}. A {@code Probe} can be used to
* trigger a probe manually (provided the correct arguments are passed to
* it), or to check a probe to see if anything is currently tracing it.
*
* A tracing check can be used to avoid lengthy work that might be
* needed to set up the probe's arguments. However, checking
* whether the probe is enabled generally takes the same amount of time
* as actually triggering the probe. So, you should only check a probe's status
* without triggering it if setting up the arguments is very expensive.
*
* Users do not need to implement this interface: instances are
* created automatically by the system when a {@code Provider)} instance is
* created.
*
* @since 1.7
*/
public interface Probe {
/**
* Checks whether there is an active trace of this probe.
*
* @return true if an active trace is detected.
*/
boolean isEnabled();
/**
* Determines whether a tracepoint is enabled.
*
* Typically, users do not need to use this method. It is called
* automatically when a Provider's instance method is called. Calls to
* this method expect the arguments to match the declared parameters for
* the method associated with the probe.
*
* @param args the parameters to pass to the method.
* @throws IllegalArgumentException if the provided parameters do not
* match the method declaration for this probe.
*/
void trigger(Object ... args);
}