net.sf.basedb.core.signal
Class Signal

java.lang.Object
  net.sf.basedb.core.signal.Signal

public class Signal
extends Object

Represents a signal that can be sent to a class implementing the SignalTarget interface. Signals must be registered before they can be used. Use getSignals() to get a list of signals that have been registered. A signal can only be registered once.

Version:

2.6

Author:

nicklas

Last modified

$Date: 2010-09-02 14:09:15 +0200 (Thu, 02 Sep 2010) $

Field Summary

static Signal	ABORT The ABORT signal, that requests that the receiver should clean up and die.
private String	description
private String	id
private String	name
static Signal	SHUTDOWN The SHUTDOWN signal, that requests that the receiver should clean up and die.
private static Map<String,Signal>	signals Holds all registered signals.

Constructor Summary

private

Signal(String id, String name, String description)

Method Summary

boolean	equals(Object other) Two signals are equal if they have the same ID.
String	getDescription() Get the description of the what the signal means and how receivers should behave when the signal is sent to them
String	getId() Get the signal ID.
String	getName() Get the short name of the signal.
static Signal	getSignal(String id) Get the signal with a given ID.
static Collection<Signal>	getSignals() Get all registered signals.
int	hashCode() The hashcode for a signal is the same as the hashcode for the ID.
static Signal	registerSignal(String id, String name, String description) Register a signal.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

ABORT

public static final Signal ABORT

The ABORT signal, that requests that the receiver should clean up and die. This signal is typically sent to a plug-in when the user manually requests that a job is aborted. It is also sent when the system is shutting down to plug-ins that doesn't support the SHUTDOWN signal.

SHUTDOWN

public static final Signal SHUTDOWN

The SHUTDOWN signal, that requests that the receiver should clean up and die. When the system is up again the receiver may continue were it was stopped if supported. Otherwise, this signal should be treated as ABORT.

Since:

2.16

signals

private static Map<String,Signal> signals

Holds all registered signals.

id

private final String id

name

private final String name

description

private final String description

Constructor Detail

Signal

private Signal(String id,
               String name,
               String description)

Method Detail

registerSignal

public static Signal registerSignal(String id,
                                    String name,
                                    String description)

Register a signal.

Parameters:

id - The ID of the signal. This must be unique. If another signal with the same ID already exists, this method does nothing.

name - The short name of the signal

description - A description of the what the signal means and how receivers should behave when the signal is sent to them

Returns:

The Signal object

getSignal

public static Signal getSignal(String id)

Get the signal with a given ID.

Parameters:

id - The signal ID.

Returns:

The Signal object, or null if no signal with the given ID has been registered

See Also:

getSignals()

getSignals

public static Collection<Signal> getSignals()

Get all registered signals. The returned collection can't be modified.

Returns:

A Collection with all registered signals

See Also:

getSignal(String)

toString

public String toString()

Overrides:

toString in class Object

Returns:

The name of the signal.

equals

public boolean equals(Object other)

Two signals are equal if they have the same ID.

Overrides:

equals in class Object

hashCode

public int hashCode()

The hashcode for a signal is the same as the hashcode for the ID.

Overrides:

hashCode in class Object

getId

public String getId()

Get the signal ID. The ID must be unique among all registered signals.

getName

public String getName()

Get the short name of the signal.

getDescription

public String getDescription()

Get the description of the what the signal means and how receivers should behave when the signal is sent to them