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package com.sun.tracing;


The Probe interface represents a tracepoint. A Probe instance is obtained by calling the Provider.getProbe() method of a provider instance created by ProviderFactory.createProvider(). A 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 Provider) instance is created. 


Since:1.7
/**
 * 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.
 * <p>
 * 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.
 * <p>
 * Users do not need to implement this interface: instances are
 * created automatically by the system when a {@code Provider)} instance is
 * created.
 * <p>
 * @since 1.7
 */

public interface Probe {
    
Checks whether there is an active trace of this probe.

Returns:true if an active trace is detected.
/**
     * 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.

Params:
  • args – the parameters to pass to the method.
Throws:
/**
     * 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);
}