/*
* Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* 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.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package sun.management;
import java.lang.management.MemoryUsage;
import java.util.Iterator;
import java.util.Map;
import java.util.HashMap;
/**
* An abstract sensor.
*
* <p>
* A <tt>AbstractSensor</tt> object consists of two attributes:
* <ul>
* <li><tt>on</tt> is a boolean flag indicating if a sensor is
* triggered. This flag will be set or cleared by the
* component that owns the sensor.</li>
* <li><tt>count</tt> is the total number of times that a sensor
* has been triggered.</li>
* </ul>
*
* @author Mandy Chung
* @since 1.5
*/
public abstract class Sensor {
private Object lock;
private String name;
private long count;
private boolean on;
/**
* Constructs a <tt>Sensor</tt> object.
*
* @param name The name of this sensor.
*/
public Sensor(String name) {
this.name = name;
this.count = 0;
this.on = false;
this.lock = new Object();
}
/**
* Returns the name of this sensor.
*
* @return the name of this sensor.
*/
public String getName() {
return name;
}
/**
* Returns the total number of times that this sensor has been triggered.
*
* @return the total number of times that this sensor has been triggered.
*/
public long getCount() {
synchronized (lock) {
return count;
}
}
/**
* Tests if this sensor is currently on.
*
* @return <tt>true</tt> if the sensor is currently on;
* <tt>false</tt> otherwise.
*
*/
public boolean isOn() {
synchronized (lock) {
return on;
}
}
/**
* Triggers this sensor. This method first sets this sensor on
* and increments its sensor count.
*/
public void trigger() {
synchronized (lock) {
on = true;
count++;
}
triggerAction();
}
/**
* Triggers this sensor. This method sets this sensor on
* and increments the count with the input <tt>increment</tt>.
*/
public void trigger(int increment) {
synchronized (lock) {
on = true;
count += increment;
// Do something here...
}
triggerAction();
}
/**
* Triggers this sensor piggybacking a memory usage object.
* This method sets this sensor on
* and increments the count with the input <tt>increment</tt>.
*/
public void trigger(int increment, MemoryUsage usage) {
synchronized (lock) {
on = true;
count += increment;
// Do something here...
}
triggerAction(usage);
}
/**
* Clears this sensor.
*/
public void clear() {
synchronized (lock) {
on = false;
}
clearAction();
}
/**
* Clears this sensor
* and increments the count with the input <tt>increment</tt>.
*/
public void clear(int increment) {
synchronized (lock) {
on = false;
count += increment;
}
clearAction();
}
public String toString() {
return "Sensor - " + getName() +
(isOn() ? " on " : " off ") +
" count = " + getCount();
}
abstract void triggerAction();
abstract void triggerAction(MemoryUsage u);
abstract void clearAction();
}