javax.swing: public class: InputMap

javax.swing
public class: InputMap [javadoc | source]

java.lang.Object
   javax.swing.InputMap

All Implemented Interfaces:
Serializable

Direct Known Subclasses:
ComponentInputMapUIResource, ComponentInputMap, InputMapUIResource, KeymapWrapper, RootPaneInputMap

InputMap provides a binding between an input event (currently only KeyStrokes are used) and an Object. InputMaps are usually used with an ActionMap, to determine an Action to perform when a key is pressed. An InputMap can have a parent that is searched for bindings not defined in the InputMap.

As with ActionMap if you create a cycle, eg:

InputMap am = new InputMap();
InputMap bm = new InputMap():
am.setParent(bm);
bm.setParent(am);

some of the methods will cause a StackOverflowError to be thrown.

author: Scott - Violet

since: 1.3 -

Constructor:

Constructor:
public InputMap() { } Creates an `InputMap` with no parent and no mappings.

 public InputMap() {

}

Creates an InputMap with no parent and no mappings.

Method from javax.swing.InputMap Summary:
allKeys, clear, get, getParent, keys, put, remove, setParent, size

Methods from java.lang.Object:
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method from javax.swing.InputMap Detail:
public KeyStroke[] allKeys() { int count = size(); InputMap parent = getParent(); if (count == 0) { if (parent != null) { return parent.allKeys(); } return keys(); } if (parent == null) { return keys(); } KeyStroke[] keys = keys(); KeyStroke[] pKeys = parent.allKeys(); if (pKeys == null) { return keys; } if (keys == null) { // Should only happen if size() != keys.length, which should only // happen if mutated from multiple threads (or a bogus subclass). return pKeys; } HashMap keyMap = new HashMap(); int counter; for (counter = keys.length - 1; counter >= 0; counter--) { keyMap.put(keys[counter], keys[counter]); } for (counter = pKeys.length - 1; counter >= 0; counter--) { keyMap.put(pKeys[counter], pKeys[counter]); } KeyStroke[] allKeys = new KeyStroke[keyMap.size()]; return (KeyStroke[])keyMap.keySet().toArray(allKeys); } Returns an array of the `KeyStroke`s defined in this `InputMap` and its parent. This differs from `keys()` in that this method includes the keys defined in the parent.
public void clear() { if (arrayTable != null) { arrayTable.clear(); } } Removes all the mappings from this `InputMap`.
public Object get(KeyStroke keyStroke) { if (arrayTable == null) { InputMap parent = getParent(); if (parent != null) { return parent.get(keyStroke); } return null; } Object value = arrayTable.get(keyStroke); if (value == null) { InputMap parent = getParent(); if (parent != null) { return parent.get(keyStroke); } } return value; } Returns the binding for `keyStroke`, messaging the parent `InputMap` if the binding is not locally defined.
public InputMap getParent() { return parent; } Gets this `InputMap`'s parent.
public KeyStroke[] keys() { if (arrayTable == null) { return null; } KeyStroke[] keys = new KeyStroke[arrayTable.size()]; arrayTable.getKeys(keys); return keys; } Returns the `KeyStroke`s that are bound in this `InputMap`.
public void put(KeyStroke keyStroke, Object actionMapKey) { if (keyStroke == null) { return; } if (actionMapKey == null) { remove(keyStroke); } else { if (arrayTable == null) { arrayTable = new ArrayTable(); } arrayTable.put(keyStroke, actionMapKey); } } Adds a binding for `keyStroke` to `actionMapKey`. If `actionMapKey` is null, this removes the current binding for `keyStroke`.
public void remove(KeyStroke key) { if (arrayTable != null) { arrayTable.remove(key); } } Removes the binding for `key` from this `InputMap`.
public void setParent(InputMap map) { this.parent = map; } Sets this `InputMap`'s parent.
public int size() { if (arrayTable == null) { return 0; } return arrayTable.size(); } Returns the number of `KeyStroke` bindings.

Method from javax.swing.InputMap Detail:

 public KeyStroke[] allKeys() {
        int             count = size();
        InputMap        parent = getParent();
        if (count == 0) {
            if (parent != null) {
                return parent.allKeys();
            }
            return keys();
        }
        if (parent == null) {
            return keys();
        }
        KeyStroke[]    keys = keys();
        KeyStroke[]    pKeys =  parent.allKeys();
        if (pKeys == null) {
            return keys;
        }
        if (keys == null) {
            // Should only happen if size() != keys.length, which should only
            // happen if mutated from multiple threads (or a bogus subclass).
            return pKeys;
        }
        HashMap        keyMap = new HashMap();
        int            counter;
        for (counter = keys.length - 1; counter  >= 0; counter--) {
            keyMap.put(keys[counter], keys[counter]);
        }
        for (counter = pKeys.length - 1; counter  >= 0; counter--) {
            keyMap.put(pKeys[counter], pKeys[counter]);
        }
        KeyStroke[]    allKeys = new KeyStroke[keyMap.size()];
        return (KeyStroke[])keyMap.keySet().toArray(allKeys);
}

KeyStroke

InputMap

keys()

 public  void clear() {
        if (arrayTable != null) {
            arrayTable.clear();
        }
}

InputMap

 public Object get(KeyStroke keyStroke) {
        if (arrayTable == null) {
            InputMap    parent = getParent();
            if (parent != null) {
                return parent.get(keyStroke);
            }
            return null;
        }
        Object value = arrayTable.get(keyStroke);
        if (value == null) {
            InputMap    parent = getParent();
            if (parent != null) {
                return parent.get(keyStroke);
            }
        }
        return value;
}

keyStroke

InputMap

 public InputMap getParent() {
        return parent;
}

InputMap

 public KeyStroke[] keys() {
        if (arrayTable == null) {
            return null;
        }
        KeyStroke[] keys = new KeyStroke[arrayTable.size()];
        arrayTable.getKeys(keys);
        return keys;
}

KeyStroke

InputMap

 public  void put(KeyStroke keyStroke,
    Object actionMapKey) {
        if (keyStroke == null) {
            return;
        }
        if (actionMapKey == null) {
            remove(keyStroke);
        }
        else {
            if (arrayTable == null) {
                arrayTable = new ArrayTable();
            }
            arrayTable.put(keyStroke, actionMapKey);
        }
}

keyStroke

actionMapKey

keyStroke

 public  void remove(KeyStroke key) {
        if (arrayTable != null) {
            arrayTable.remove(key);
        }
}

key

InputMap

 public  void setParent(InputMap map) {
        this.parent = map;
}

InputMap

 public int size() {
        if (arrayTable == null) {
            return 0;
        }
        return arrayTable.size();
}

KeyStroke