https://openjdk.java.net/ 
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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 */

package jdk.internal.event;


Base class for events, to be subclassed in order to define events and their
fields.

/**
 * Base class for events, to be subclassed in order to define events and their
 * fields.
 */
public abstract class Event {
    
Sole constructor, for invocation by subclass constructors, typically
implicit.

/**
     * Sole constructor, for invocation by subclass constructors, typically
     * implicit.
     */
    protected Event() {
    }

    
Starts the timing of this event.

/**
     * Starts the timing of this event.
     */
    public void begin() {
    }

    
Ends the timing of this event. The end method must be invoked after the begin method. 
/**
     * Ends the timing of this event.
     *
     * The {@code end} method must be invoked after the {@code begin} method.
     */
    public void end() {
    }

    
Writes the field values, time stamp, and event duration.

 If the event starts with an invocation of the begin method, but does not end with an explicit invocation of the end method, then the event ends when the commit method is invoked. 
/**
     * Writes the field values, time stamp, and event duration.
     * <p>
     * If the event starts with an invocation of the {@code begin} method, but does
     * not end with an explicit invocation of the {@code end} method, then the event
     * ends when the {@code commit} method is invoked.
     */
    public void commit() {
    }

    
Returns true if the event is enabled, false otherwise 
Returns:true if event is enabled, false otherwise
/**
     * Returns {@code true} if the event is enabled, {@code false} otherwise
     *
     * @return {@code true} if event is enabled, {@code false} otherwise
     */
    public boolean isEnabled() {
        return false;
    }

    
Returns true if the event is enabled and if the duration is within the threshold for the event, false otherwise. 
Returns:true if the event can be written, false otherwise
/**
     * Returns {@code true} if the event is enabled and if the duration is within
     * the threshold for the event, {@code false} otherwise.
     *
     * @return {@code true} if the event can be written, {@code false} otherwise
     */
    public boolean shouldCommit() {
        return false;
    }

    
Sets a field value.

Params:
  • index – the index of the field to set
  • value – value to set, can be null
Throws:
/**
     * Sets a field value.
     *
     * @param index the index of the field to set
     * @param value value to set, can be {@code null}
     * @throws UnsupportedOperationException if functionality is not supported
     * @throws IndexOutOfBoundsException if {@code index} is less than {@code 0} or
     *         greater than or equal to the number of fields specified for the event
     */
    public void set(int index, Object value) {
    }
}