Action
* interface. Standard behaviors like the get and set methods for
* Action object properties (icon, text, and enabled) are defined
* here. The developer need only subclass this abstract class and
* define the actionPerformed method.
*
* Warning:
* Serialized objects of this class will not be compatible with
* future Swing releases. The current serialization support is
* appropriate for short term storage or RMI between applications running
* the same version of Swing. As of 1.4, support for long term storage
* of all JavaBeansTM
* has been added to the java.beans package.
* Please see {@link java.beans.XMLEncoder}.
*
* @author Georges Saab
* @see Action
*/
public abstract class AbstractAction implements Action, Cloneable, Serializable
{
/**
* Whether or not actions should reconfigure all properties on null.
*/
private static Boolean RECONFIGURE_ON_NULL;
/**
* Specifies whether action is enabled; the default is true.
*/
protected boolean enabled = true;
/**
* Contains the array of key bindings.
*/
private transient ArrayTable arrayTable;
/**
* Whether or not to reconfigure all action properties from the
* specified event.
*/
static boolean shouldReconfigure(PropertyChangeEvent e) {
if (e.getPropertyName() == null) {
synchronized(AbstractAction.class) {
if (RECONFIGURE_ON_NULL == null) {
RECONFIGURE_ON_NULL = Boolean.valueOf(
AccessController.doPrivileged(new GetPropertyAction(
"swing.actions.reconfigureOnNull", "false")));
}
return RECONFIGURE_ON_NULL;
}
}
return false;
}
/**
* Sets the enabled state of a component from an Action.
*
* @param c the Component to set the enabled state on
* @param a the Action to set the enabled state from, may be null
*/
static void setEnabledFromAction(JComponent c, Action a) {
c.setEnabled((a != null) ? a.isEnabled() : true);
}
/**
* Sets the tooltip text of a component from an Action.
*
* @param c the Component to set the tooltip text on
* @param a the Action to set the tooltip text from, may be null
*/
static void setToolTipTextFromAction(JComponent c, Action a) {
c.setToolTipText(a != null ?
(String)a.getValue(Action.SHORT_DESCRIPTION) : null);
}
static boolean hasSelectedKey(Action a) {
return (a != null && a.getValue(Action.SELECTED_KEY) != null);
}
static boolean isSelected(Action a) {
return Boolean.TRUE.equals(a.getValue(Action.SELECTED_KEY));
}
/**
* Creates an {@code Action}.
*/
public AbstractAction() {
}
/**
* Creates an {@code Action} with the specified name.
*
* @param name the name ({@code Action.NAME}) for the action; a
* value of {@code null} is ignored
*/
public AbstractAction(String name) {
putValue(Action.NAME, name);
}
/**
* Creates an {@code Action} with the specified name and small icon.
*
* @param name the name ({@code Action.NAME}) for the action; a
* value of {@code null} is ignored
* @param icon the small icon ({@code Action.SMALL_ICON}) for the action; a
* value of {@code null} is ignored
*/
public AbstractAction(String name, Icon icon) {
this(name);
putValue(Action.SMALL_ICON, icon);
}
/**
* Gets the Object associated with the specified key.
*
* @param key a string containing the specified key
* @return the binding Object stored with this key; if there
* are no keys, it will return null
* @see Action#getValue
*/
public Object getValue(String key) {
if (key == "enabled") {
return enabled;
}
if (arrayTable == null) {
return null;
}
return arrayTable.get(key);
}
/**
* Sets the Value associated with the specified key.
*
* @param key the String that identifies the stored object
* @param newValue the Object to store using this key
* @see Action#putValue
*/
public void putValue(String key, Object newValue) {
Object oldValue = null;
if (key == "enabled") {
// Treat putValue("enabled") the same way as a call to setEnabled.
// If we don't do this it means the two may get out of sync, and a
// bogus property change notification would be sent.
//
// To avoid dependencies between putValue & setEnabled this
// directly changes enabled. If we instead called setEnabled
// to change enabled, it would be possible for stack
// overflow in the case where a developer implemented setEnabled
// in terms of putValue.
if (newValue == null || !(newValue instanceof Boolean)) {
newValue = false;
}
oldValue = enabled;
enabled = (Boolean)newValue;
} else {
if (arrayTable == null) {
arrayTable = new ArrayTable();
}
if (arrayTable.containsKey(key))
oldValue = arrayTable.get(key);
// Remove the entry for key if newValue is null
// else put in the newValue for key.
if (newValue == null) {
arrayTable.remove(key);
} else {
arrayTable.put(key,newValue);
}
}
firePropertyChange(key, oldValue, newValue);
}
/**
* Returns true if the action is enabled.
*
* @return true if the action is enabled, false otherwise
* @see Action#isEnabled
*/
public boolean isEnabled() {
return enabled;
}
/**
* Sets whether the {@code Action} is enabled. The default is {@code true}.
*
* @param newValue {@code true} to enable the action, {@code false} to
* disable it
* @see Action#setEnabled
*/
public void setEnabled(boolean newValue) {
boolean oldValue = this.enabled;
if (oldValue != newValue) {
this.enabled = newValue;
firePropertyChange("enabled",
Boolean.valueOf(oldValue), Boolean.valueOf(newValue));
}
}
/**
* Returns an array of Objects which are keys for
* which values have been set for this AbstractAction,
* or null if no keys have values set.
* @return an array of key objects, or null if no
* keys have values set
* @since 1.3
*/
public Object[] getKeys() {
if (arrayTable == null) {
return null;
}
Object[] keys = new Object[arrayTable.size()];
arrayTable.getKeys(keys);
return keys;
}
/**
* If any PropertyChangeListeners have been registered, the
* changeSupport field describes them.
*/
protected SwingPropertyChangeSupport changeSupport;
/**
* Supports reporting bound property changes. This method can be called
* when a bound property has changed and it will send the appropriate
* PropertyChangeEvent to any registered
* PropertyChangeListeners.
*/
protected void firePropertyChange(String propertyName, Object oldValue, Object newValue) {
if (changeSupport == null ||
(oldValue != null && newValue != null && oldValue.equals(newValue))) {
return;
}
changeSupport.firePropertyChange(propertyName, oldValue, newValue);
}
/**
* Adds a PropertyChangeListener to the listener list.
* The listener is registered for all properties.
*
* A PropertyChangeEvent will get fired in response to setting
* a bound property, e.g. setFont, setBackground,
* or setForeground.
* Note that if the current component is inheriting its foreground,
* background, or font from its container, then no event will be
* fired in response to a change in the inherited property.
*
* @param listener The PropertyChangeListener to be added
*
* @see Action#addPropertyChangeListener
*/
public synchronized void addPropertyChangeListener(PropertyChangeListener listener) {
if (changeSupport == null) {
changeSupport = new SwingPropertyChangeSupport(this);
}
changeSupport.addPropertyChangeListener(listener);
}
/**
* Removes a PropertyChangeListener from the listener list.
* This removes a PropertyChangeListener that was registered
* for all properties.
*
* @param listener the PropertyChangeListener to be removed
*
* @see Action#removePropertyChangeListener
*/
public synchronized void removePropertyChangeListener(PropertyChangeListener listener) {
if (changeSupport == null) {
return;
}
changeSupport.removePropertyChangeListener(listener);
}
/**
* Returns an array of all the PropertyChangeListeners added
* to this AbstractAction with addPropertyChangeListener().
*
* @return all of the PropertyChangeListeners added or an empty
* array if no listeners have been added
* @since 1.4
*/
public synchronized PropertyChangeListener[] getPropertyChangeListeners() {
if (changeSupport == null) {
return new PropertyChangeListener[0];
}
return changeSupport.getPropertyChangeListeners();
}
/**
* Clones the abstract action. This gives the clone
* its own copy of the key/value list,
* which is not handled for you by Object.clone().
**/
protected Object clone() throws CloneNotSupportedException {
AbstractAction newAction = (AbstractAction)super.clone();
synchronized(this) {
if (arrayTable != null) {
newAction.arrayTable = (ArrayTable)arrayTable.clone();
}
}
return newAction;
}
private void writeObject(ObjectOutputStream s) throws IOException {
// Store the default fields
s.defaultWriteObject();
// And the keys
ArrayTable.writeArrayTable(s, arrayTable);
}
private void readObject(ObjectInputStream s) throws ClassNotFoundException,
IOException {
s.defaultReadObject();
for (int counter = s.readInt() - 1; counter >= 0; counter--) {
putValue((String)s.readObject(), s.readObject());
}
}
}