| /* |
| * Copyright (c) 1999, 2017, 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 |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package javax.management.monitor; |
| |
| import static com.sun.jmx.defaults.JmxProperties.MONITOR_LOGGER; |
| import java.lang.System.Logger.Level; |
| import javax.management.ObjectName; |
| import javax.management.MBeanNotificationInfo; |
| import static javax.management.monitor.Monitor.NumericalType.*; |
| import static javax.management.monitor.MonitorNotification.*; |
| |
| /** |
| * Defines a monitor MBean designed to observe the values of a counter |
| * attribute. |
| * |
| * <P> A counter monitor sends a {@link |
| * MonitorNotification#THRESHOLD_VALUE_EXCEEDED threshold |
| * notification} when the value of the counter reaches or exceeds a |
| * threshold known as the comparison level. The notify flag must be |
| * set to <CODE>true</CODE>. |
| * |
| * <P> In addition, an offset mechanism enables particular counting |
| * intervals to be detected. If the offset value is not zero, |
| * whenever the threshold is triggered by the counter value reaching a |
| * comparison level, that comparison level is incremented by the |
| * offset value. This is regarded as taking place instantaneously, |
| * that is, before the count is incremented. Thus, for each level, |
| * the threshold triggers an event notification every time the count |
| * increases by an interval equal to the offset value. |
| * |
| * <P> If the counter can wrap around its maximum value, the modulus |
| * needs to be specified. The modulus is the value at which the |
| * counter is reset to zero. |
| * |
| * <P> If the counter difference mode is used, the value of the |
| * derived gauge is calculated as the difference between the observed |
| * counter values for two successive observations. If this difference |
| * is negative, the value of the derived gauge is incremented by the |
| * value of the modulus. The derived gauge value (V[t]) is calculated |
| * using the following method: |
| * |
| * <UL> |
| * <LI>if (counter[t] - counter[t-GP]) is positive then |
| * V[t] = counter[t] - counter[t-GP] |
| * <LI>if (counter[t] - counter[t-GP]) is negative then |
| * V[t] = counter[t] - counter[t-GP] + MODULUS |
| * </UL> |
| * |
| * This implementation of the counter monitor requires the observed |
| * attribute to be of the type integer (<CODE>Byte</CODE>, |
| * <CODE>Integer</CODE>, <CODE>Short</CODE>, <CODE>Long</CODE>). |
| * |
| * |
| * @since 1.5 |
| */ |
| public class CounterMonitor extends Monitor implements CounterMonitorMBean { |
| |
| /* |
| * ------------------------------------------ |
| * PACKAGE CLASSES |
| * ------------------------------------------ |
| */ |
| |
| static class CounterMonitorObservedObject extends ObservedObject { |
| |
| public CounterMonitorObservedObject(ObjectName observedObject) { |
| super(observedObject); |
| } |
| |
| public final synchronized Number getThreshold() { |
| return threshold; |
| } |
| public final synchronized void setThreshold(Number threshold) { |
| this.threshold = threshold; |
| } |
| public final synchronized Number getPreviousScanCounter() { |
| return previousScanCounter; |
| } |
| public final synchronized void setPreviousScanCounter( |
| Number previousScanCounter) { |
| this.previousScanCounter = previousScanCounter; |
| } |
| public final synchronized boolean getModulusExceeded() { |
| return modulusExceeded; |
| } |
| public final synchronized void setModulusExceeded( |
| boolean modulusExceeded) { |
| this.modulusExceeded = modulusExceeded; |
| } |
| public final synchronized Number getDerivedGaugeExceeded() { |
| return derivedGaugeExceeded; |
| } |
| public final synchronized void setDerivedGaugeExceeded( |
| Number derivedGaugeExceeded) { |
| this.derivedGaugeExceeded = derivedGaugeExceeded; |
| } |
| public final synchronized boolean getDerivedGaugeValid() { |
| return derivedGaugeValid; |
| } |
| public final synchronized void setDerivedGaugeValid( |
| boolean derivedGaugeValid) { |
| this.derivedGaugeValid = derivedGaugeValid; |
| } |
| public final synchronized boolean getEventAlreadyNotified() { |
| return eventAlreadyNotified; |
| } |
| public final synchronized void setEventAlreadyNotified( |
| boolean eventAlreadyNotified) { |
| this.eventAlreadyNotified = eventAlreadyNotified; |
| } |
| public final synchronized NumericalType getType() { |
| return type; |
| } |
| public final synchronized void setType(NumericalType type) { |
| this.type = type; |
| } |
| |
| private Number threshold; |
| private Number previousScanCounter; |
| private boolean modulusExceeded; |
| private Number derivedGaugeExceeded; |
| private boolean derivedGaugeValid; |
| private boolean eventAlreadyNotified; |
| private NumericalType type; |
| } |
| |
| /* |
| * ------------------------------------------ |
| * PRIVATE VARIABLES |
| * ------------------------------------------ |
| */ |
| |
| /** |
| * Counter modulus. |
| * <BR>The default value is a null Integer object. |
| */ |
| private Number modulus = INTEGER_ZERO; |
| |
| /** |
| * Counter offset. |
| * <BR>The default value is a null Integer object. |
| */ |
| private Number offset = INTEGER_ZERO; |
| |
| /** |
| * Flag indicating if the counter monitor notifies when exceeding |
| * the threshold. The default value is set to |
| * <CODE>false</CODE>. |
| */ |
| private boolean notify = false; |
| |
| /** |
| * Flag indicating if the counter difference mode is used. If the |
| * counter difference mode is used, the derived gauge is the |
| * difference between two consecutive observed values. Otherwise, |
| * the derived gauge is directly the value of the observed |
| * attribute. The default value is set to <CODE>false</CODE>. |
| */ |
| private boolean differenceMode = false; |
| |
| /** |
| * Initial counter threshold. This value is used to initialize |
| * the threshold when a new object is added to the list and reset |
| * the threshold to its initial value each time the counter |
| * resets. |
| */ |
| private Number initThreshold = INTEGER_ZERO; |
| |
| private static final String[] types = { |
| RUNTIME_ERROR, |
| OBSERVED_OBJECT_ERROR, |
| OBSERVED_ATTRIBUTE_ERROR, |
| OBSERVED_ATTRIBUTE_TYPE_ERROR, |
| THRESHOLD_ERROR, |
| THRESHOLD_VALUE_EXCEEDED |
| }; |
| |
| private static final MBeanNotificationInfo[] notifsInfo = { |
| new MBeanNotificationInfo( |
| types, |
| "javax.management.monitor.MonitorNotification", |
| "Notifications sent by the CounterMonitor MBean") |
| }; |
| |
| /* |
| * ------------------------------------------ |
| * CONSTRUCTORS |
| * ------------------------------------------ |
| */ |
| |
| /** |
| * Default constructor. |
| */ |
| public CounterMonitor() { |
| } |
| |
| /* |
| * ------------------------------------------ |
| * PUBLIC METHODS |
| * ------------------------------------------ |
| */ |
| |
| /** |
| * Starts the counter monitor. |
| */ |
| public synchronized void start() { |
| if (isActive()) { |
| MONITOR_LOGGER.log(Level.TRACE, "the monitor is already active"); |
| return; |
| } |
| // Reset values. |
| // |
| for (ObservedObject o : observedObjects) { |
| final CounterMonitorObservedObject cmo = |
| (CounterMonitorObservedObject) o; |
| cmo.setThreshold(initThreshold); |
| cmo.setModulusExceeded(false); |
| cmo.setEventAlreadyNotified(false); |
| cmo.setPreviousScanCounter(null); |
| } |
| doStart(); |
| } |
| |
| /** |
| * Stops the counter monitor. |
| */ |
| public synchronized void stop() { |
| doStop(); |
| } |
| |
| // GETTERS AND SETTERS |
| //-------------------- |
| |
| /** |
| * Gets the derived gauge of the specified object, if this object is |
| * contained in the set of observed MBeans, or <code>null</code> otherwise. |
| * |
| * @param object the name of the object whose derived gauge is to |
| * be returned. |
| * |
| * @return The derived gauge of the specified object. |
| * |
| */ |
| @Override |
| public synchronized Number getDerivedGauge(ObjectName object) { |
| return (Number) super.getDerivedGauge(object); |
| } |
| |
| /** |
| * Gets the derived gauge timestamp of the specified object, if |
| * this object is contained in the set of observed MBeans, or |
| * <code>0</code> otherwise. |
| * |
| * @param object the name of the object whose derived gauge |
| * timestamp is to be returned. |
| * |
| * @return The derived gauge timestamp of the specified object. |
| * |
| */ |
| @Override |
| public synchronized long getDerivedGaugeTimeStamp(ObjectName object) { |
| return super.getDerivedGaugeTimeStamp(object); |
| } |
| |
| /** |
| * Gets the current threshold value of the specified object, if |
| * this object is contained in the set of observed MBeans, or |
| * <code>null</code> otherwise. |
| * |
| * @param object the name of the object whose threshold is to be |
| * returned. |
| * |
| * @return The threshold value of the specified object. |
| * |
| */ |
| public synchronized Number getThreshold(ObjectName object) { |
| final CounterMonitorObservedObject o = |
| (CounterMonitorObservedObject) getObservedObject(object); |
| if (o == null) |
| return null; |
| |
| // If the counter that is monitored rolls over when it reaches a |
| // maximum value, then the modulus value needs to be set to that |
| // maximum value. The threshold will then also roll over whenever |
| // it strictly exceeds the modulus value. When the threshold rolls |
| // over, it is reset to the value that was specified through the |
| // latest call to the monitor's setInitThreshold method, before |
| // any offsets were applied. |
| // |
| if (offset.longValue() > 0L && |
| modulus.longValue() > 0L && |
| o.getThreshold().longValue() > modulus.longValue()) { |
| return initThreshold; |
| } else { |
| return o.getThreshold(); |
| } |
| } |
| |
| /** |
| * Gets the initial threshold value common to all observed objects. |
| * |
| * @return The initial threshold. |
| * |
| * @see #setInitThreshold |
| * |
| */ |
| public synchronized Number getInitThreshold() { |
| return initThreshold; |
| } |
| |
| /** |
| * Sets the initial threshold value common to all observed objects. |
| * |
| * <BR>The current threshold of every object in the set of |
| * observed MBeans is updated consequently. |
| * |
| * @param value The initial threshold value. |
| * |
| * @exception IllegalArgumentException The specified |
| * threshold is null or the threshold value is less than zero. |
| * |
| * @see #getInitThreshold |
| * |
| */ |
| public synchronized void setInitThreshold(Number value) |
| throws IllegalArgumentException { |
| |
| if (value == null) { |
| throw new IllegalArgumentException("Null threshold"); |
| } |
| if (value.longValue() < 0L) { |
| throw new IllegalArgumentException("Negative threshold"); |
| } |
| |
| if (initThreshold.equals(value)) |
| return; |
| initThreshold = value; |
| |
| // Reset values. |
| // |
| int index = 0; |
| for (ObservedObject o : observedObjects) { |
| resetAlreadyNotified(o, index++, THRESHOLD_ERROR_NOTIFIED); |
| final CounterMonitorObservedObject cmo = |
| (CounterMonitorObservedObject) o; |
| cmo.setThreshold(value); |
| cmo.setModulusExceeded(false); |
| cmo.setEventAlreadyNotified(false); |
| } |
| } |
| |
| /** |
| * Returns the derived gauge of the first object in the set of |
| * observed MBeans. |
| * |
| * @return The derived gauge. |
| * |
| * @deprecated As of JMX 1.2, replaced by |
| * {@link #getDerivedGauge(ObjectName)} |
| */ |
| @Deprecated |
| public synchronized Number getDerivedGauge() { |
| if (observedObjects.isEmpty()) { |
| return null; |
| } else { |
| return (Number) observedObjects.get(0).getDerivedGauge(); |
| } |
| } |
| |
| /** |
| * Gets the derived gauge timestamp of the first object in the set |
| * of observed MBeans. |
| * |
| * @return The derived gauge timestamp. |
| * |
| * @deprecated As of JMX 1.2, replaced by |
| * {@link #getDerivedGaugeTimeStamp(ObjectName)} |
| */ |
| @Deprecated |
| public synchronized long getDerivedGaugeTimeStamp() { |
| if (observedObjects.isEmpty()) { |
| return 0; |
| } else { |
| return observedObjects.get(0).getDerivedGaugeTimeStamp(); |
| } |
| } |
| |
| /** |
| * Gets the threshold value of the first object in the set of |
| * observed MBeans. |
| * |
| * @return The threshold value. |
| * |
| * @see #setThreshold |
| * |
| * @deprecated As of JMX 1.2, replaced by {@link #getThreshold(ObjectName)} |
| */ |
| @Deprecated |
| public synchronized Number getThreshold() { |
| return getThreshold(getObservedObject()); |
| } |
| |
| /** |
| * Sets the initial threshold value. |
| * |
| * @param value The initial threshold value. |
| * |
| * @exception IllegalArgumentException The specified threshold is |
| * null or the threshold value is less than zero. |
| * |
| * @see #getThreshold() |
| * |
| * @deprecated As of JMX 1.2, replaced by {@link #setInitThreshold} |
| */ |
| @Deprecated |
| public synchronized void setThreshold(Number value) |
| throws IllegalArgumentException { |
| setInitThreshold(value); |
| } |
| |
| /** |
| * Gets the offset value common to all observed MBeans. |
| * |
| * @return The offset value. |
| * |
| * @see #setOffset |
| */ |
| public synchronized Number getOffset() { |
| return offset; |
| } |
| |
| /** |
| * Sets the offset value common to all observed MBeans. |
| * |
| * @param value The offset value. |
| * |
| * @exception IllegalArgumentException The specified |
| * offset is null or the offset value is less than zero. |
| * |
| * @see #getOffset |
| */ |
| public synchronized void setOffset(Number value) |
| throws IllegalArgumentException { |
| |
| if (value == null) { |
| throw new IllegalArgumentException("Null offset"); |
| } |
| if (value.longValue() < 0L) { |
| throw new IllegalArgumentException("Negative offset"); |
| } |
| |
| if (offset.equals(value)) |
| return; |
| offset = value; |
| |
| int index = 0; |
| for (ObservedObject o : observedObjects) { |
| resetAlreadyNotified(o, index++, THRESHOLD_ERROR_NOTIFIED); |
| } |
| } |
| |
| /** |
| * Gets the modulus value common to all observed MBeans. |
| * |
| * @see #setModulus |
| * |
| * @return The modulus value. |
| */ |
| public synchronized Number getModulus() { |
| return modulus; |
| } |
| |
| /** |
| * Sets the modulus value common to all observed MBeans. |
| * |
| * @param value The modulus value. |
| * |
| * @exception IllegalArgumentException The specified |
| * modulus is null or the modulus value is less than zero. |
| * |
| * @see #getModulus |
| */ |
| public synchronized void setModulus(Number value) |
| throws IllegalArgumentException { |
| |
| if (value == null) { |
| throw new IllegalArgumentException("Null modulus"); |
| } |
| if (value.longValue() < 0L) { |
| throw new IllegalArgumentException("Negative modulus"); |
| } |
| |
| if (modulus.equals(value)) |
| return; |
| modulus = value; |
| |
| // Reset values. |
| // |
| int index = 0; |
| for (ObservedObject o : observedObjects) { |
| resetAlreadyNotified(o, index++, THRESHOLD_ERROR_NOTIFIED); |
| final CounterMonitorObservedObject cmo = |
| (CounterMonitorObservedObject) o; |
| cmo.setModulusExceeded(false); |
| } |
| } |
| |
| /** |
| * Gets the notification's on/off switch value common to all |
| * observed MBeans. |
| * |
| * @return <CODE>true</CODE> if the counter monitor notifies when |
| * exceeding the threshold, <CODE>false</CODE> otherwise. |
| * |
| * @see #setNotify |
| */ |
| public synchronized boolean getNotify() { |
| return notify; |
| } |
| |
| /** |
| * Sets the notification's on/off switch value common to all |
| * observed MBeans. |
| * |
| * @param value The notification's on/off switch value. |
| * |
| * @see #getNotify |
| */ |
| public synchronized void setNotify(boolean value) { |
| if (notify == value) |
| return; |
| notify = value; |
| } |
| |
| /** |
| * Gets the difference mode flag value common to all observed MBeans. |
| * |
| * @return <CODE>true</CODE> if the difference mode is used, |
| * <CODE>false</CODE> otherwise. |
| * |
| * @see #setDifferenceMode |
| */ |
| public synchronized boolean getDifferenceMode() { |
| return differenceMode; |
| } |
| |
| /** |
| * Sets the difference mode flag value common to all observed MBeans. |
| * |
| * @param value The difference mode flag value. |
| * |
| * @see #getDifferenceMode |
| */ |
| public synchronized void setDifferenceMode(boolean value) { |
| if (differenceMode == value) |
| return; |
| differenceMode = value; |
| |
| // Reset values. |
| // |
| for (ObservedObject o : observedObjects) { |
| final CounterMonitorObservedObject cmo = |
| (CounterMonitorObservedObject) o; |
| cmo.setThreshold(initThreshold); |
| cmo.setModulusExceeded(false); |
| cmo.setEventAlreadyNotified(false); |
| cmo.setPreviousScanCounter(null); |
| } |
| } |
| |
| /** |
| * Returns a <CODE>NotificationInfo</CODE> object containing the |
| * name of the Java class of the notification and the notification |
| * types sent by the counter monitor. |
| */ |
| @Override |
| public MBeanNotificationInfo[] getNotificationInfo() { |
| return notifsInfo.clone(); |
| } |
| |
| /* |
| * ------------------------------------------ |
| * PRIVATE METHODS |
| * ------------------------------------------ |
| */ |
| |
| /** |
| * Updates the derived gauge attribute of the observed object. |
| * |
| * @param scanCounter The value of the observed attribute. |
| * @param o The observed object. |
| * @return <CODE>true</CODE> if the derived gauge value is valid, |
| * <CODE>false</CODE> otherwise. The derived gauge value is |
| * invalid when the differenceMode flag is set to |
| * <CODE>true</CODE> and it is the first notification (so we |
| * haven't 2 consecutive values to update the derived gauge). |
| */ |
| private synchronized boolean updateDerivedGauge( |
| Object scanCounter, CounterMonitorObservedObject o) { |
| |
| boolean is_derived_gauge_valid; |
| |
| // The counter difference mode is used. |
| // |
| if (differenceMode) { |
| |
| // The previous scan counter has been initialized. |
| // |
| if (o.getPreviousScanCounter() != null) { |
| setDerivedGaugeWithDifference((Number)scanCounter, null, o); |
| |
| // If derived gauge is negative it means that the |
| // counter has wrapped around and the value of the |
| // threshold needs to be reset to its initial value. |
| // |
| if (((Number)o.getDerivedGauge()).longValue() < 0L) { |
| if (modulus.longValue() > 0L) { |
| setDerivedGaugeWithDifference((Number)scanCounter, |
| modulus, o); |
| } |
| o.setThreshold(initThreshold); |
| o.setEventAlreadyNotified(false); |
| } |
| is_derived_gauge_valid = true; |
| } |
| // The previous scan counter has not been initialized. |
| // We cannot update the derived gauge... |
| // |
| else { |
| is_derived_gauge_valid = false; |
| } |
| o.setPreviousScanCounter((Number)scanCounter); |
| } |
| // The counter difference mode is not used. |
| // |
| else { |
| o.setDerivedGauge((Number)scanCounter); |
| is_derived_gauge_valid = true; |
| } |
| return is_derived_gauge_valid; |
| } |
| |
| /** |
| * Updates the notification attribute of the observed object |
| * and notifies the listeners only once if the notify flag |
| * is set to <CODE>true</CODE>. |
| * @param o The observed object. |
| */ |
| private synchronized MonitorNotification updateNotifications( |
| CounterMonitorObservedObject o) { |
| |
| MonitorNotification n = null; |
| |
| // Send notification if notify is true. |
| // |
| if (!o.getEventAlreadyNotified()) { |
| if (((Number)o.getDerivedGauge()).longValue() >= |
| o.getThreshold().longValue()) { |
| if (notify) { |
| n = new MonitorNotification(THRESHOLD_VALUE_EXCEEDED, |
| this, |
| 0, |
| 0, |
| "", |
| null, |
| null, |
| null, |
| o.getThreshold()); |
| } |
| if (!differenceMode) { |
| o.setEventAlreadyNotified(true); |
| } |
| } |
| } else { |
| if (MONITOR_LOGGER.isLoggable(Level.TRACE)) { |
| final StringBuilder strb = new StringBuilder() |
| .append("The notification:") |
| .append("\n\tNotification observed object = ") |
| .append(o.getObservedObject()) |
| .append("\n\tNotification observed attribute = ") |
| .append(getObservedAttribute()) |
| .append("\n\tNotification threshold level = ") |
| .append(o.getThreshold()) |
| .append("\n\tNotification derived gauge = ") |
| .append(o.getDerivedGauge()) |
| .append("\nhas already been sent"); |
| MONITOR_LOGGER.log(Level.TRACE, strb::toString); |
| } |
| } |
| |
| return n; |
| } |
| |
| /** |
| * Updates the threshold attribute of the observed object. |
| * @param o The observed object. |
| */ |
| private synchronized void updateThreshold(CounterMonitorObservedObject o) { |
| |
| // Calculate the new threshold value if the threshold has been |
| // exceeded and if the offset value is greater than zero. |
| // |
| if (((Number)o.getDerivedGauge()).longValue() >= |
| o.getThreshold().longValue()) { |
| |
| if (offset.longValue() > 0L) { |
| |
| // Increment the threshold until its value is greater |
| // than the one for the current derived gauge. |
| // |
| long threshold_value = o.getThreshold().longValue(); |
| while (((Number)o.getDerivedGauge()).longValue() >= |
| threshold_value) { |
| threshold_value += offset.longValue(); |
| } |
| |
| // Set threshold attribute. |
| // |
| switch (o.getType()) { |
| case INTEGER: |
| o.setThreshold(Integer.valueOf((int)threshold_value)); |
| break; |
| case BYTE: |
| o.setThreshold(Byte.valueOf((byte)threshold_value)); |
| break; |
| case SHORT: |
| o.setThreshold(Short.valueOf((short)threshold_value)); |
| break; |
| case LONG: |
| o.setThreshold(Long.valueOf(threshold_value)); |
| break; |
| default: |
| // Should never occur... |
| MONITOR_LOGGER.log(Level.TRACE, |
| "the threshold type is invalid"); |
| break; |
| } |
| |
| // If the counter can wrap around when it reaches |
| // its maximum and we are not dealing with counter |
| // differences then we need to reset the threshold |
| // to its initial value too. |
| // |
| if (!differenceMode) { |
| if (modulus.longValue() > 0L) { |
| if (o.getThreshold().longValue() > |
| modulus.longValue()) { |
| o.setModulusExceeded(true); |
| o.setDerivedGaugeExceeded( |
| (Number) o.getDerivedGauge()); |
| } |
| } |
| } |
| |
| // Threshold value has been modified so we can notify again. |
| // |
| o.setEventAlreadyNotified(false); |
| } else { |
| o.setModulusExceeded(true); |
| o.setDerivedGaugeExceeded((Number) o.getDerivedGauge()); |
| } |
| } |
| } |
| |
| /** |
| * Sets the derived gauge of the specified observed object when the |
| * differenceMode flag is set to <CODE>true</CODE>. Integer types |
| * only are allowed. |
| * |
| * @param scanCounter The value of the observed attribute. |
| * @param mod The counter modulus value. |
| * @param o The observed object. |
| */ |
| private synchronized void setDerivedGaugeWithDifference( |
| Number scanCounter, Number mod, CounterMonitorObservedObject o) { |
| /* We do the arithmetic using longs here even though the |
| result may end up in a smaller type. Since |
| l == (byte)l (mod 256) for any long l, |
| (byte) ((byte)l1 + (byte)l2) == (byte) (l1 + l2), |
| and likewise for subtraction. So it's the same as if |
| we had done the arithmetic in the smaller type.*/ |
| |
| long derived = |
| scanCounter.longValue() - o.getPreviousScanCounter().longValue(); |
| if (mod != null) |
| derived += modulus.longValue(); |
| |
| switch (o.getType()) { |
| case INTEGER: o.setDerivedGauge(Integer.valueOf((int) derived)); break; |
| case BYTE: o.setDerivedGauge(Byte.valueOf((byte) derived)); break; |
| case SHORT: o.setDerivedGauge(Short.valueOf((short) derived)); break; |
| case LONG: o.setDerivedGauge(Long.valueOf(derived)); break; |
| default: |
| // Should never occur... |
| MONITOR_LOGGER.log(Level.TRACE, |
| "the threshold type is invalid"); |
| break; |
| } |
| } |
| |
| /* |
| * ------------------------------------------ |
| * PACKAGE METHODS |
| * ------------------------------------------ |
| */ |
| |
| /** |
| * Factory method for ObservedObject creation. |
| * |
| * @since 1.6 |
| */ |
| @Override |
| ObservedObject createObservedObject(ObjectName object) { |
| final CounterMonitorObservedObject cmo = |
| new CounterMonitorObservedObject(object); |
| cmo.setThreshold(initThreshold); |
| cmo.setModulusExceeded(false); |
| cmo.setEventAlreadyNotified(false); |
| cmo.setPreviousScanCounter(null); |
| return cmo; |
| } |
| |
| /** |
| * This method globally sets the derived gauge type for the given |
| * "object" and "attribute" after checking that the type of the |
| * supplied observed attribute value is one of the value types |
| * supported by this monitor. |
| */ |
| @Override |
| synchronized boolean isComparableTypeValid(ObjectName object, |
| String attribute, |
| Comparable<?> value) { |
| final CounterMonitorObservedObject o = |
| (CounterMonitorObservedObject) getObservedObject(object); |
| if (o == null) |
| return false; |
| |
| // Check that the observed attribute is of type "Integer". |
| // |
| if (value instanceof Integer) { |
| o.setType(INTEGER); |
| } else if (value instanceof Byte) { |
| o.setType(BYTE); |
| } else if (value instanceof Short) { |
| o.setType(SHORT); |
| } else if (value instanceof Long) { |
| o.setType(LONG); |
| } else { |
| return false; |
| } |
| return true; |
| } |
| |
| @Override |
| synchronized Comparable<?> getDerivedGaugeFromComparable( |
| ObjectName object, |
| String attribute, |
| Comparable<?> value) { |
| final CounterMonitorObservedObject o = |
| (CounterMonitorObservedObject) getObservedObject(object); |
| if (o == null) |
| return null; |
| |
| // Check if counter has wrapped around. |
| // |
| if (o.getModulusExceeded()) { |
| if (((Number)o.getDerivedGauge()).longValue() < |
| o.getDerivedGaugeExceeded().longValue()) { |
| o.setThreshold(initThreshold); |
| o.setModulusExceeded(false); |
| o.setEventAlreadyNotified(false); |
| } |
| } |
| |
| // Update the derived gauge attributes and check the |
| // validity of the new value. The derived gauge value |
| // is invalid when the differenceMode flag is set to |
| // true and it is the first notification, i.e. we |
| // haven't got 2 consecutive values to update the |
| // derived gauge. |
| // |
| o.setDerivedGaugeValid(updateDerivedGauge(value, o)); |
| |
| return (Comparable<?>) o.getDerivedGauge(); |
| } |
| |
| @Override |
| synchronized void onErrorNotification(MonitorNotification notification) { |
| final CounterMonitorObservedObject o = (CounterMonitorObservedObject) |
| getObservedObject(notification.getObservedObject()); |
| if (o == null) |
| return; |
| |
| // Reset values. |
| // |
| o.setModulusExceeded(false); |
| o.setEventAlreadyNotified(false); |
| o.setPreviousScanCounter(null); |
| } |
| |
| @Override |
| synchronized MonitorNotification buildAlarmNotification( |
| ObjectName object, |
| String attribute, |
| Comparable<?> value) { |
| final CounterMonitorObservedObject o = |
| (CounterMonitorObservedObject) getObservedObject(object); |
| if (o == null) |
| return null; |
| |
| // Notify the listeners and update the threshold if |
| // the updated derived gauge value is valid. |
| // |
| final MonitorNotification alarm; |
| if (o.getDerivedGaugeValid()) { |
| alarm = updateNotifications(o); |
| updateThreshold(o); |
| } else { |
| alarm = null; |
| } |
| return alarm; |
| } |
| |
| /** |
| * Tests if the threshold, offset and modulus of the specified observed |
| * object are of the same type as the counter. Only integer types are |
| * allowed. |
| * |
| * Note: |
| * If the optional offset or modulus have not been initialized, their |
| * default value is an Integer object with a value equal to zero. |
| * |
| * @param object The observed object. |
| * @param attribute The observed attribute. |
| * @param value The sample value. |
| * @return <CODE>true</CODE> if type is the same, |
| * <CODE>false</CODE> otherwise. |
| */ |
| @Override |
| synchronized boolean isThresholdTypeValid(ObjectName object, |
| String attribute, |
| Comparable<?> value) { |
| final CounterMonitorObservedObject o = |
| (CounterMonitorObservedObject) getObservedObject(object); |
| if (o == null) |
| return false; |
| |
| Class<? extends Number> c = classForType(o.getType()); |
| return (c.isInstance(o.getThreshold()) && |
| isValidForType(offset, c) && |
| isValidForType(modulus, c)); |
| } |
| } |