java/11 : java.desktop/java/awt/event/ActionEvent.java

ActionEvent
https://openjdk.java.net/
GPLv2 + Classpath Exception
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package java.awt.event;

import java.awt.AWTEvent;
import java.lang.annotation.Native;

A semantic event which indicates that a component-defined action occurred. This high-level event is generated by a component (such as a Button) when the component-specific action occurs (such as being pressed). The event is passed to every ActionListener object that registered to receive such events using the component's addActionListener method. 
Note: To invoke an ActionEvent on a Button using the keyboard, use the Space bar. 
 The object that implements the ActionListener interface gets this ActionEvent when the event occurs. The listener is therefore spared the details of processing individual mouse movements and mouse clicks, and can instead process a "meaningful" (semantic) event like "button pressed". 
 An unspecified behavior will be caused if the id parameter of any particular ActionEvent instance is not in the range from ACTION_FIRST to ACTION_LAST. 
Author: Carl Quinn
See Also: ActionListener
Tutorial: How to Write an Action Listener
Since: 1.1/**
 * A semantic event which indicates that a component-defined action occurred.
 * This high-level event is generated by a component (such as a
 * {@code Button}) when
 * the component-specific action occurs (such as being pressed).
 * The event is passed to every {@code ActionListener} object
 * that registered to receive such events using the component's
 * {@code addActionListener} method.
 * <p>
 * <b>Note:</b> To invoke an {@code ActionEvent} on a
 * {@code Button} using the keyboard, use the Space bar.
 * <P>
 * The object that implements the {@code ActionListener} interface
 * gets this {@code ActionEvent} when the event occurs. The listener
 * is therefore spared the details of processing individual mouse movements
 * and mouse clicks, and can instead process a "meaningful" (semantic)
 * event like "button pressed".
 * <p>
 * An unspecified behavior will be caused if the {@code id} parameter
 * of any particular {@code ActionEvent} instance is not
 * in the range from {@code ACTION_FIRST} to {@code ACTION_LAST}.
 *
 * @see ActionListener
 * @see <a href="http://docs.oracle.com/javase/tutorial/uiswing/events/actionlistener.html">Tutorial: How to Write an Action Listener</a>
 *
 * @author Carl Quinn
 * @since 1.1
 */
public class ActionEvent extends AWTEvent {

    The shift modifier. An indicator that the shift key was held
down during the event.
/**
     * The shift modifier. An indicator that the shift key was held
     * down during the event.
     */
    public static final int SHIFT_MASK = 1 << 0;

    The control modifier. An indicator that the control key was held
down during the event.
/**
     * The control modifier. An indicator that the control key was held
     * down during the event.
     */
    public static final int CTRL_MASK = 1 << 1;

    The meta modifier. An indicator that the meta key was held
down during the event.
/**
     * The meta modifier. An indicator that the meta key was held
     * down during the event.
     */
    public static final int META_MASK = 1 << 2;

    The alt modifier. An indicator that the alt key was held
down during the event.
/**
     * The alt modifier. An indicator that the alt key was held
     * down during the event.
     */
    public static final int ALT_MASK = 1 << 3;


    The first number in the range of ids used for action events.
/**
     * The first number in the range of ids used for action events.
     */
    public static final int ACTION_FIRST                = 1001;

    The last number in the range of ids used for action events.
/**
     * The last number in the range of ids used for action events.
     */
    public static final int ACTION_LAST                 = 1001;

    This event id indicates that a meaningful action occurred.
/**
     * This event id indicates that a meaningful action occurred.
     */
    @Native public static final int ACTION_PERFORMED    = ACTION_FIRST; //Event.ACTION_EVENT

    The nonlocalized string that gives more details
of what actually caused the event.
This information is very specific to the component
that fired it.
See Also: getActionCommand
@serial /**
     * The nonlocalized string that gives more details
     * of what actually caused the event.
     * This information is very specific to the component
     * that fired it.

     * @serial
     * @see #getActionCommand
     */
    String actionCommand;

    Timestamp of when this event occurred. Because an ActionEvent is a high-
level, semantic event, the timestamp is typically the same as an
underlying InputEvent.
See Also: getWhen
@serial /**
     * Timestamp of when this event occurred. Because an ActionEvent is a high-
     * level, semantic event, the timestamp is typically the same as an
     * underlying InputEvent.
     *
     * @serial
     * @see #getWhen
     */
    long when;

    This represents the key modifier that was selected,
and is used to determine the state of the selected key.
If no modifier has been selected it will default to
zero.
See Also: getModifiers
@serial /**
     * This represents the key modifier that was selected,
     * and is used to determine the state of the selected key.
     * If no modifier has been selected it will default to
     * zero.
     *
     * @serial
     * @see #getModifiers
     */
    int modifiers;

    /*
     * JDK 1.1 serialVersionUID
     */
    private static final long serialVersionUID = -7671078796273832149L;

    Constructs an ActionEvent object.  This method throws an IllegalArgumentException if source is null. A null command string is legal, but not recommended. 
Params: source –  The object that originated the event
id –  An integer that identifies the event. For information on allowable values, see the class description for ActionEvent
command – A string that may specify a command (possibly one
               of several) associated with the event
Throws: IllegalArgumentException – if source is null
See Also: EventObject.getSource()
AWTEvent.getID()
getActionCommand()/**
     * Constructs an {@code ActionEvent} object.
     * <p>
     * This method throws an
     * {@code IllegalArgumentException} if {@code source}
     * is {@code null}.
     * A {@code null command} string is legal,
     * but not recommended.
     *
     * @param source  The object that originated the event
     * @param id      An integer that identifies the event.
     *                     For information on allowable values, see
     *                     the class description for {@link ActionEvent}
     * @param command A string that may specify a command (possibly one
     *                of several) associated with the event
     * @throws IllegalArgumentException if {@code source} is null
     * @see #getSource()
     * @see #getID()
     * @see #getActionCommand()
     */
    public ActionEvent(Object source, int id, String command) {
        this(source, id, command, 0);
    }

    Constructs an ActionEvent object with modifier keys.  This method throws an IllegalArgumentException if source is null. A null command string is legal, but not recommended. 
Params: source –  The object that originated the event
id –  An integer that identifies the event. For information on allowable values, see the class description for ActionEvent
command – A string that may specify a command (possibly one
               of several) associated with the event
modifiers – The modifier keys down during event
                 (shift, ctrl, alt, meta).
                 Passing negative parameter is not recommended.
                 Zero value means that no modifiers were passed
Throws: IllegalArgumentException – if source is null
See Also: EventObject.getSource()
AWTEvent.getID()
getActionCommand()
getModifiers()/**
     * Constructs an {@code ActionEvent} object with modifier keys.
     * <p>
     * This method throws an
     * {@code IllegalArgumentException} if {@code source}
     * is {@code null}.
     * A {@code null command} string is legal,
     * but not recommended.
     *
     * @param source  The object that originated the event
     * @param id      An integer that identifies the event.
     *                     For information on allowable values, see
     *                     the class description for {@link ActionEvent}
     * @param command A string that may specify a command (possibly one
     *                of several) associated with the event
     * @param modifiers The modifier keys down during event
     *                  (shift, ctrl, alt, meta).
     *                  Passing negative parameter is not recommended.
     *                  Zero value means that no modifiers were passed
     * @throws IllegalArgumentException if {@code source} is null
     * @see #getSource()
     * @see #getID()
     * @see #getActionCommand()
     * @see #getModifiers()
     */
    public ActionEvent(Object source, int id, String command, int modifiers) {
        this(source, id, command, 0, modifiers);
    }

    Constructs an ActionEvent object with the specified modifier keys and timestamp.  This method throws an IllegalArgumentException if source is null. A null command string is legal, but not recommended. 
Params: source –    The object that originated the event
id –  An integer that identifies the event. For information on allowable values, see the class description for ActionEvent
command – A string that may specify a command (possibly one
               of several) associated with the event
modifiers – The modifier keys down during event
                 (shift, ctrl, alt, meta).
                 Passing negative parameter is not recommended.
                 Zero value means that no modifiers were passed
when –   A long that gives the time the event occurred.
              Passing negative or zero value
              is not recommended
Throws: IllegalArgumentException – if source is null
See Also: EventObject.getSource()
AWTEvent.getID()
getActionCommand()
getModifiers()
getWhen()
Since: 1.4/**
     * Constructs an {@code ActionEvent} object with the specified
     * modifier keys and timestamp.
     * <p>
     * This method throws an
     * {@code IllegalArgumentException} if {@code source}
     * is {@code null}.
     * A {@code null command} string is legal,
     * but not recommended.
     *
     * @param source    The object that originated the event
     * @param id      An integer that identifies the event.
     *                     For information on allowable values, see
     *                     the class description for {@link ActionEvent}
     * @param command A string that may specify a command (possibly one
     *                of several) associated with the event
     * @param modifiers The modifier keys down during event
     *                  (shift, ctrl, alt, meta).
     *                  Passing negative parameter is not recommended.
     *                  Zero value means that no modifiers were passed
     * @param when   A long that gives the time the event occurred.
     *               Passing negative or zero value
     *               is not recommended
     * @throws IllegalArgumentException if {@code source} is null
     * @see #getSource()
     * @see #getID()
     * @see #getActionCommand()
     * @see #getModifiers()
     * @see #getWhen()
     *
     * @since 1.4
     */
    public ActionEvent(Object source, int id, String command, long when,
                       int modifiers) {
        super(source, id);
        this.actionCommand = command;
        this.when = when;
        this.modifiers = modifiers;
    }

    Returns the command string associated with this action.
This string allows a "modal" component to specify one of several
commands, depending on its state. For example, a single button might
toggle between "show details" and "hide details". The source object
and the event would be the same in each case, but the command string
would identify the intended action.
 Note that if a null command string was passed to the constructor for this ActionEvent, this this method returns null. 
Returns: the string identifying the command for this event/**
     * Returns the command string associated with this action.
     * This string allows a "modal" component to specify one of several
     * commands, depending on its state. For example, a single button might
     * toggle between "show details" and "hide details". The source object
     * and the event would be the same in each case, but the command string
     * would identify the intended action.
     * <p>
     * Note that if a {@code null} command string was passed
     * to the constructor for this {@code ActionEvent}, this
     * this method returns {@code null}.
     *
     * @return the string identifying the command for this event
     */
    public String getActionCommand() {
        return actionCommand;
    }

    Returns the timestamp of when this event occurred. Because an
ActionEvent is a high-level, semantic event, the timestamp is typically
the same as an underlying InputEvent.
Returns: this event's timestamp
Since: 1.4/**
     * Returns the timestamp of when this event occurred. Because an
     * ActionEvent is a high-level, semantic event, the timestamp is typically
     * the same as an underlying InputEvent.
     *
     * @return this event's timestamp
     * @since 1.4
     */
    public long getWhen() {
        return when;
    }

    Returns the modifier keys held down during this action event.
Returns: the bitwise-or of the modifier constants/**
     * Returns the modifier keys held down during this action event.
     *
     * @return the bitwise-or of the modifier constants
     */
    public int getModifiers() {
        return modifiers;
    }

    Returns a parameter string identifying this action event.
This method is useful for event-logging and for debugging.
Returns: a string identifying the event and its associated command/**
     * Returns a parameter string identifying this action event.
     * This method is useful for event-logging and for debugging.
     *
     * @return a string identifying the event and its associated command
     */
    @SuppressWarnings("deprecation")
    public String paramString() {
        String typeStr;
        switch(id) {
          case ACTION_PERFORMED:
              typeStr = "ACTION_PERFORMED";
              break;
          default:
              typeStr = "unknown type";
        }
        return typeStr + ",cmd="+actionCommand+",when="+when+",modifiers="+
            KeyEvent.getKeyModifiersText(modifiers);
    }
}
Author:	Carl Quinn
See Also:	ActionListener Tutorial: How to Write an Action Listener
Since:	1.1
Params:	source – The object that originated the event id – An integer that identifies the event. For information on allowable values, see the class description for `ActionEvent` command – A string that may specify a command (possibly one of several) associated with the event
Throws:	IllegalArgumentException – if `source` is null
See Also:	EventObject.getSource() AWTEvent.getID() getActionCommand()
/

java/ 11/ java.desktop/java/awt/event/ActionEvent.java
