org.lsst.ccs.gconsole.plugins.monitor

Class MonitorField

java.lang.Object

org.lsst.ccs.gconsole.plugins.monitor.MonitorField

public class MonitorField
extends Object

Descriptor of a field that can be displayed by monitoring views. Static constants of this class enumerate standard types of monitored values. Additional instances may be created at run time.

Instances can be registered as default handlers for data channel attribute keys.

Equality and hash code are based on the object identity.

Author:

onoprien

Field Summary

Fields

Modifier and Type	Field and Description
static MonitorField	ALERT_HIGH
static MonitorField	ALERT_LOW
static MonitorField	DESCR
static MonitorField	HIGH_ALARM
static MonitorField	HIGH_WARN
protected String	key
static MonitorField	LOW_ALARM
static MonitorField	LOW_WARN
static MonitorField	NAME
static MonitorField	NULL
protected FormattedValue	template
protected String	title
static MonitorField	UNITS
static MonitorField	VALUE

Constructor Summary

Constructors

Constructor and Description
MonitorField(String key, String title, FormattedValue template) Constructs an instance.

Method Summary

Modifier and Type	Method and Description
FormattedValue	format(AgentChannel channel) Returns the current formatted value of this field in the specified data channel, or null if this field does not define custom formatting.
static List<MonitorField>	getAffectedFields(Collection<String> keys)
static List<MonitorField>	getAffectedFields(Collection<String> keys, Collection<MonitorField> fields)
static List<MonitorField>	getDefaultFields(Collection<String> keys)
static MonitorField	getInstance(String key) Returns an instance registered as the default handler for the specified attribute key.
String	getKey() Returns a unique getKey of this field.
Set<String>	getKeys() Returns a set of keys of data channel attributes that might effect the value of this field or its formatting.
String	getTitle() Returns human readable title associated with this field.
Object	getValue(AgentChannel channel) Returns the current value of this field in the specified data channel, or null if the channel does not contain a value for this field.
boolean	isUpdatable()
static void	registerInstance(MonitorField field) Registers the specified instance as the default handler for the attribute identified by the key returned by its getKey() method.
void	setValue(Object value, AgentChannel channel)
String	toString() Returns the human readable title of this field.
static MonitorField	valueOf(String key) Returns an instance registered as the default handler for the attribute identified by the specified key, or null if no such instance exists.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

NULL

public static final MonitorField NULL

NAME

public static final MonitorField NAME

VALUE

public static final MonitorField VALUE

UNITS

public static final MonitorField UNITS

LOW_ALARM

public static final MonitorField LOW_ALARM

LOW_WARN

public static final MonitorField LOW_WARN

ALERT_LOW

public static final MonitorField ALERT_LOW

HIGH_ALARM

public static final MonitorField HIGH_ALARM

HIGH_WARN

public static final MonitorField HIGH_WARN

ALERT_HIGH

public static final MonitorField ALERT_HIGH

DESCR

public static final MonitorField DESCR

key

protected final String key

title

protected final String title

template

protected final FormattedValue template

Constructor Detail

MonitorField

public MonitorField(String key,
                    String title,
                    FormattedValue template)

Constructs an instance.

Parameters:

key - Attribute key. Unless overridden, getKey() and getKeys() methods will return this key and a singleton set containing this key, respectively. The getValue(channel) method will return the value of the data channel attribute identified by this key.

title - Human readable title.

template - Formatted value template.

Method Detail

registerInstance

public static void registerInstance(MonitorField field)

Registers the specified instance as the default handler for the attribute identified by the key returned by its getKey() method.

Parameters:

field - Instance to register.

Throws:

IllegalArgumentException - if an instance with this key already registered.

getInstance

public static MonitorField getInstance(String key)

Returns an instance registered as the default handler for the specified attribute key. If a default handler for the specified key is already registered, it is returned; otherwise, if a standard field with the specified name (static field in this class) exists, it is returned; otherwise, a new instance is created with default parameters:
new MonitorField(key, key, null).

Parameters:

key - Attribute key.

Returns:

Registered instance for the specified key.

valueOf

public static MonitorField valueOf(String key)

Returns an instance registered as the default handler for the attribute identified by the specified key, or null if no such instance exists.

Parameters:

key - Attribute key.

Returns:

Registered instance, or null if no such instance exists.

getDefaultFields

public static List<MonitorField> getDefaultFields(Collection<String> keys)

getAffectedFields

public static List<MonitorField> getAffectedFields(Collection<String> keys,
                                                   Collection<MonitorField> fields)

getAffectedFields

public static List<MonitorField> getAffectedFields(Collection<String> keys)

getValue

public Object getValue(AgentChannel channel)

Returns the current value of this field in the specified data channel, or null if the channel does not contain a value for this field.

Parameters:

channel - Data channel.

Returns:

Current value of this field.

setValue

public void setValue(Object value,
                     AgentChannel channel)

getKey

public String getKey()

Returns a unique getKey of this field.

Returns:

Name of this field.

getTitle

public String getTitle()

Returns human readable title associated with this field.

Returns:

Title of this field.

getKeys

public Set<String> getKeys()

Returns a set of keys of data channel attributes that might effect the value of this field or its formatting. For fields that are not updated throughout lifetime of a subsystem, this method returns an empty set.

Returns:

Set of attribute keys that might affect this field.

isUpdatable

public boolean isUpdatable()

format

public FormattedValue format(AgentChannel channel)

Returns the current formatted value of this field in the specified data channel, or null if this field does not define custom formatting. In the latter case, clients are expected to format the raw value returned by the getValue(AgentChannel) method, possibly taking into account values returned by other getters.

The default implementation returns a new instance with the value field set to the object returned by getValue(), and all other fields set according to the template supplied to this field constructor. Some of the standard fields override this method, providing custom formatting.

Parameters:

channel - Data channel.

Returns:

Fully or partially formatted value of this field.

toString

public String toString()

Returns the human readable title of this field.

Overrides:

toString in class Object

Returns:

Title of this field.