javax.slee.facilities.TimerOptions Maven / Gradle / Ivy
package javax.slee.facilities;
import java.io.Serializable;
/**
* The TimerOptions class specifies the behavior of a timer when it is set.
*
* Timeout -
* Under normal conditions and expected workload, a SLEE and its Timer Facility should be
* able to fire timer events on time. However, under overload conditions, or when the SLEE
* is not running, the Timer Facility may not be able to do so. The timeout value allows
* some flexibility in deciding when a scheduled timer becomes late. A timer is considered
* late if the Timer Facility cannot fire a scheduled timer event by its scheduled expiry
* time + timer timeout. For a periodic timer, the timeout must be less than the timer's
* period.
*
* Preserving Missed Timer Events -
* The default timer options cause the Timer Facility to only generate the last event
* in a sequence of late timer events for a timer that fires late. This guarantees at
* least one timer event (the last, for a periodic timer) will be generated for a timer.
* However an SBB can still choose to receive all or none of the late timer events if desired.
*
* Persistent Timers -
* Deprecated in SLEE 1.1 - This option has been deprecated. The semantics of
* persistent timers were unclear as the definition of persistent implied by this option
* was inconsistent with the general use of the term "persistent" in the rest of the
* specification.
*/
public class TimerOptions implements Serializable {
/**
* Create a TimerOptions object that describes the default timer behavior.
* The default timer behavior is:
*
* - the timeout is the SLEE's default timeout period.
*
- only the last in a sequence of late timer events is preserved.
*
* The deprecated persistent option is set to false by this constructor.
*/
public TimerOptions() {
this(0, TimerPreserveMissed.LAST);
}
/**
* Create a TimerOptions object that has the same behavioral properties as
* another TimerOptions.
* @param options the TimerOptions object to copy.
*/
public TimerOptions(TimerOptions options) {
this(options.persistent, options.timeout, options.preserveMissed);
}
/**
* Create a TimerOptions object for the specified timer behavior.
* @param persistent boolean value indicating whether the timer should be persistent or not.
* @param timeout the timeout period for the timer (specified in milliseconds).
* @param preserveMissed the behavior of late timers.
* @throws NullPointerException if preserveMissed is null.
* @throws IllegalArgumentException if timeout is less than zero.
* @deprecated This constructor specifies the value of the persistent option, which
* has been deprecated. It has been replaced with {@link #TimerOptions(long, TimerPreserveMissed)}.
*/
public TimerOptions(boolean persistent, long timeout, TimerPreserveMissed preserveMissed) throws NullPointerException, IllegalArgumentException {
setPersistent(persistent);
setTimeout(timeout);
setPreserveMissed(preserveMissed);
}
/**
* Create a TimerOptions object for the specified timer behavior.
* The deprecated persistent option is set to false by this constructor.
* @param timeout the timeout period for the timer (specified in milliseconds).
* @param preserveMissed the behavior of late timers.
* @throws NullPointerException if preserveMissed is null.
* @throws IllegalArgumentException if timeout is less than zero.
* @since SLEE 1.1
*/
public TimerOptions(long timeout, TimerPreserveMissed preserveMissed) throws NullPointerException, IllegalArgumentException {
setPersistent(false);
setTimeout(timeout);
setPreserveMissed(preserveMissed);
}
/**
* Test if the persistent timer flag is set.
* @return true if the timer should be persistent, false otherwise.
* @deprecated the persistent option has been deprecated.
*/
public final boolean isPersistent() {
return persistent;
}
/**
* Set the persistent timer flag.
* @param persistent boolean value indicating whether the timer should be persistent or not.
* @deprecated the persistent option has been deprecated.
*/
public final void setPersistent(boolean persistent) {
this.persistent = persistent;
}
/**
* Get the timeout period.
* @return the timeout period.
*/
public final long getTimeout() {
return timeout;
}
/**
* Set the timeout period.
* @param timeout the timeout period (specified in milliseconds).
* @throws IllegalArgumentException if timeout less than zero.
*/
public final void setTimeout(long timeout) throws IllegalArgumentException {
if (timeout < 0) throw new IllegalArgumentException("timeout cannot be less than zero");
this.timeout = timeout;
}
/**
* Get the value of the preserve-missed option.
* @return the value of the preserve-missed option.
*/
public final TimerPreserveMissed getPreserveMissed() {
return preserveMissed;
}
/**
* Set the value of the preserve missed option.
* @param preserveMissed the behavior of late timers.
* @throws NullPointerException if preserveMissed is null.
*/
public final void setPreserveMissed(TimerPreserveMissed preserveMissed) throws NullPointerException {
if (preserveMissed == null) throw new NullPointerException("preserveMissed is null");
this.preserveMissed = preserveMissed;
}
/**
* Compare this timer options object for equality with another.
* @param obj the object to compare this with.
* @return true if obj is an instance of this class
* representing the same timer options as this, false otherwise.
*/
public boolean equals(Object obj) {
if (obj == this) return true;
if (!(obj instanceof TimerOptions)) return false;
TimerOptions that = (TimerOptions)obj;
return (this.persistent == that.persistent)
&& (this.timeout == that.timeout)
&& (this.preserveMissed.equals(that.preserveMissed));
}
/**
* Get a hash code value for this timer options object.
* @return a hash code value.
*/
public int hashCode() {
return (int)timeout | (persistent ? 0x1000 : 0) | (preserveMissed.hashCode() << 20);
}
/**
* Get the textual representation of the timer options object.
* @return the textual representation of the timer options object.
*/
public String toString() {
return "TimerOptions[persistent=" + persistent + ",timeout=" + timeout + ",preserve missed=" + preserveMissed + "]";
}
private boolean persistent;
private long timeout;
private TimerPreserveMissed preserveMissed;
}