UIDefaults (Java Platform SE 8 )
Keywords: javax.swing.UIDefaults class
Date: 2026-01-21

javax.swing

## Class UIDefaults

- java.lang.Object
- - java.util.Dictionary<K,V>
  - - java.util.Hashtable<Object,Object>
    - - javax.swing.UIDefaults

- All Implemented Interfaces:
    Serializable, Cloneable, Map<Object,Object>

      public class UIDefaults
      extends Hashtable<Object,Object>

  A table of defaults for Swing components. Applications can set/get default values via the `UIManager`.

  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 JavaBeans™ has been added to the `java.beans` package. Please see `XMLEncoder`.

  See Also:
    `UIManager`

- - ### Nested Class Summary

    Nested Classes
    Modifier and Type | Class and Description
    --- | ---
    `static interface` | `UIDefaults.ActiveValue` This class enables one to store an entry in the defaults table that's constructed each time it's looked up with one of the `getXXX(key)` methods.
    `static class` | `UIDefaults.LazyInputMap` `LazyInputMap` will create a `InputMap` in its `createValue` method.
    `static interface` | `UIDefaults.LazyValue` This class enables one to store an entry in the defaults table that isn't constructed until the first time it's looked up with one of the `getXXX(key)` methods.
    `static class` | `UIDefaults.ProxyLazyValue` This class provides an implementation of `LazyValue` which can be used to delay loading of the Class for the instance to be created.

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `UIDefaults()` Creates an empty defaults table.
    `UIDefaults(int initialCapacity, float loadFactor)` Creates an empty defaults table with the specified initial capacity and load factor.
    `UIDefaults(Object[] keyValueList)` Creates a defaults table initialized with the specified key/value pairs.

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `addPropertyChangeListener(PropertyChangeListener listener)` Adds a `PropertyChangeListener` to the listener list.
    `void` | `addResourceBundle(String bundleName)` Adds a resource bundle to the list of resource bundles that are searched for localized values.
    `protected void` | `firePropertyChange(String propertyName, Object oldValue, Object newValue)` Support for reporting bound property changes.
    `Object` | `get(Object key)` Returns the value for key.
    `Object` | `get(Object key, Locale l)` Returns the value for key associated with the given locale.
    `boolean` | `getBoolean(Object key)` If the value of `key` is boolean, return the boolean value, otherwise return false.
    `boolean` | `getBoolean(Object key, Locale l)` If the value of `key` for the given `Locale` is boolean, return the boolean value, otherwise return false.
    `Border` | `getBorder(Object key)` If the value of `key` is a `Border` return it, otherwise return `null`.
    `Border` | `getBorder(Object key, Locale l)` If the value of `key` for the given `Locale` is a `Border` return it, otherwise return `null`.
    `Color` | `getColor(Object key)` If the value of `key` is a `Color` return it, otherwise return `null`.
    `Color` | `getColor(Object key, Locale l)` If the value of `key` for the given `Locale` is a `Color` return it, otherwise return `null`.
    `Locale` | `getDefaultLocale()` Returns the default locale.
    `Dimension` | `getDimension(Object key)` If the value of `key` is a `Dimension` return it, otherwise return `null`.
    `Dimension` | `getDimension(Object key, Locale l)` If the value of `key` for the given `Locale` is a `Dimension` return it, otherwise return `null`.
    `Font` | `getFont(Object key)` If the value of `key` is a `Font` return it, otherwise return `null`.
    `Font` | `getFont(Object key, Locale l)` If the value of `key` for the given `Locale` is a `Font` return it, otherwise return `null`.
    `Icon` | `getIcon(Object key)` If the value of `key` is an `Icon` return it, otherwise return `null`.
    `Icon` | `getIcon(Object key, Locale l)` If the value of `key` for the given `Locale` is an `Icon` return it, otherwise return `null`.
    `Insets` | `getInsets(Object key)` If the value of `key` is an `Insets` return it, otherwise return `null`.
    `Insets` | `getInsets(Object key, Locale l)` If the value of `key` for the given `Locale` is an `Insets` return it, otherwise return `null`.
    `int` | `getInt(Object key)` If the value of `key` is an `Integer` return its integer value, otherwise return 0.
    `int` | `getInt(Object key, Locale l)` If the value of `key` for the given `Locale` is an `Integer` return its integer value, otherwise return 0.
    `PropertyChangeListener[]` | `getPropertyChangeListeners()` Returns an array of all the `PropertyChangeListener`s added to this UIDefaults with addPropertyChangeListener().
    `String` | `getString(Object key)` If the value of `key` is a `String` return it, otherwise return `null`.
    `String` | `getString(Object key, Locale l)` If the value of `key` for the given `Locale` is a `String` return it, otherwise return `null`.
    `ComponentUI` | `getUI(JComponent target)` Creates an `ComponentUI` implementation for the specified component.
    `Class<? extends ComponentUI>` | `getUIClass(String uiClassID)` Returns the L&F class that renders this component.
    `Class<? extends ComponentUI>` | `getUIClass(String uiClassID, ClassLoader uiClassLoader)` The value of `get(uidClassID)` must be the `String` name of a class that implements the corresponding `ComponentUI` class.
    `protected void` | `getUIError(String msg)` If `getUI()` fails for any reason, it calls this method before returning `null`.
    `Object` | `put(Object key, Object value)` Sets the value of `key` to `value` for all locales.
    `void` | `putDefaults(Object[] keyValueList)` Puts all of the key/value pairs in the database and unconditionally generates one `PropertyChangeEvent`.
    `void` | `removePropertyChangeListener(PropertyChangeListener listener)` Removes a `PropertyChangeListener` from the listener list.
    `void` | `removeResourceBundle(String bundleName)` Removes a resource bundle from the list of resource bundles that are searched for localized defaults.
    `void` | `setDefaultLocale(Locale l)` Sets the default locale.

    - ### Methods inherited from class java.util.Hashtable

      `clear, clone, compute, computeIfAbsent, computeIfPresent, contains, containsKey, containsValue, elements, entrySet, equals, forEach, getOrDefault, hashCode, isEmpty, keys, keySet, merge, putAll, putIfAbsent, rehash, remove, remove, replace, replace, replaceAll, size, toString, values`

    - ### Methods inherited from class java.lang.Object

      `finalize, getClass, notify, notifyAll, wait, wait, wait`

- - ### Constructor Detail

    - #### UIDefaults

          public UIDefaults()

      Creates an empty defaults table.

    - #### UIDefaults

          public UIDefaults(int initialCapacity,
                            float loadFactor)

      Creates an empty defaults table with the specified initial capacity and load factor.
      Parameters:
        `initialCapacity` - the initial capacity of the defaults table
        `loadFactor` - the load factor of the defaults table
      Since:
        1.6
      See Also:
        `Hashtable`

    - #### UIDefaults

          public UIDefaults(Object[] keyValueList)

      Creates a defaults table initialized with the specified key/value pairs. For example:

                  Object[] uiDefaults = {
                       "Font", new Font("Dialog", Font.BOLD, 12),
                      "Color", Color.red,
                       "five", new Integer(5)
                  }
                  UIDefaults myDefaults = new UIDefaults(uiDefaults);

      Parameters:
        `keyValueList` - an array of objects containing the key/value pairs

  - ### Method Detail

    - #### get

          public Object get(Object key)

      Returns the value for key. If the value is a `UIDefaults.LazyValue` then the real value is computed with `LazyValue.createValue()`, the table entry is replaced, and the real value is returned. If the value is an `UIDefaults.ActiveValue` the table entry is not replaced - the value is computed with `ActiveValue.createValue()` for each `get()` call. If the key is not found in the table then it is searched for in the list of resource bundles maintained by this object. The resource bundles are searched most recently added first using the locale returned by `getDefaultLocale`. `LazyValues` and `ActiveValues` are not supported in the resource bundles.
      Specified by:
        `get` in interface `Map<Object,Object>`
      Overrides:
        `get` in class `Hashtable<Object,Object>`
      Parameters:
        `key` - the desired key
      Returns:
        the value for `key`
      Since:
        1.4
      See Also:
        `UIDefaults.LazyValue`, `UIDefaults.ActiveValue`, `Hashtable.get(java.lang.Object)`, `getDefaultLocale()`, `addResourceBundle(java.lang.String)`

    - #### get

          public Object get(Object key,
                            Locale l)

      Returns the value for key associated with the given locale. If the value is a `UIDefaults.LazyValue` then the real value is computed with `LazyValue.createValue()`, the table entry is replaced, and the real value is returned. If the value is an `UIDefaults.ActiveValue` the table entry is not replaced - the value is computed with `ActiveValue.createValue()` for each `get()` call. If the key is not found in the table then it is searched for in the list of resource bundles maintained by this object. The resource bundles are searched most recently added first using the given locale. `LazyValues` and `ActiveValues` are not supported in the resource bundles.
      Parameters:
        `key` - the desired key
        `l` - the desired `locale`
      Returns:
        the value for `key`
      Since:
        1.4
      See Also:
        `UIDefaults.LazyValue`, `UIDefaults.ActiveValue`, `Hashtable.get(java.lang.Object)`, `addResourceBundle(java.lang.String)`

    - #### put

          public Object put(Object key,
                            Object value)

      Sets the value of `key` to `value` for all locales. If `key` is a string and the new value isn't equal to the old one, fire a `PropertyChangeEvent`. If value is `null`, the key is removed from the table.
      Specified by:
        `put` in interface `Map<Object,Object>`
      Overrides:
        `put` in class `Hashtable<Object,Object>`
      Parameters:
        `key` - the unique `Object` who's value will be used to retrieve the data value associated with it
        `value` - the new `Object` to store as data under that key
      Returns:
        the previous `Object` value, or `null`
      See Also:
        `putDefaults(java.lang.Object[])`, `Hashtable.put(K, V)`

    - #### putDefaults

          public void putDefaults(Object[] keyValueList)

      Puts all of the key/value pairs in the database and unconditionally generates one `PropertyChangeEvent`. The events oldValue and newValue will be `null` and its `propertyName` will be "UIDefaults". The key/value pairs are added for all locales.
      Parameters:
        `keyValueList` - an array of key/value pairs
      See Also:
        `put(java.lang.Object, java.lang.Object)`, `Hashtable.put(K, V)`

    - #### getFont

          public Font getFont(Object key)

      If the value of `key` is a `Font` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
      Returns:
        if the value for `key` is a `Font`, return the `Font` object; otherwise return `null`

    - #### getFont

          public Font getFont(Object key,
                              Locale l)

      If the value of `key` for the given `Locale` is a `Font` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
        `l` - the desired locale
      Returns:
        if the value for `key` and `Locale` is a `Font`, return the `Font` object; otherwise return `null`
      Since:
        1.4

    - #### getColor

          public Color getColor(Object key)

      If the value of `key` is a `Color` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
      Returns:
        if the value for `key` is a `Color`, return the `Color` object; otherwise return `null`

    - #### getColor

          public Color getColor(Object key,
                                Locale l)

      If the value of `key` for the given `Locale` is a `Color` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
        `l` - the desired locale
      Returns:
        if the value for `key` and `Locale` is a `Color`, return the `Color` object; otherwise return `null`
      Since:
        1.4

    - #### getIcon

          public Icon getIcon(Object key)

      If the value of `key` is an `Icon` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
      Returns:
        if the value for `key` is an `Icon`, return the `Icon` object; otherwise return `null`

    - #### getIcon

          public Icon getIcon(Object key,
                              Locale l)

      If the value of `key` for the given `Locale` is an `Icon` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
        `l` - the desired locale
      Returns:
        if the value for `key` and `Locale` is an `Icon`, return the `Icon` object; otherwise return `null`
      Since:
        1.4

    - #### getBorder

          public Border getBorder(Object key)

      If the value of `key` is a `Border` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
      Returns:
        if the value for `key` is a `Border`, return the `Border` object; otherwise return `null`

    - #### getBorder

          public Border getBorder(Object key,
                                  Locale l)

      If the value of `key` for the given `Locale` is a `Border` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
        `l` - the desired locale
      Returns:
        if the value for `key` and `Locale` is a `Border`, return the `Border` object; otherwise return `null`
      Since:
        1.4

    - #### getString

          public String getString(Object key)

      If the value of `key` is a `String` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
      Returns:
        if the value for `key` is a `String`, return the `String` object; otherwise return `null`

    - #### getString

          public String getString(Object key,
                                  Locale l)

      If the value of `key` for the given `Locale` is a `String` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
        `l` - the desired `Locale`
      Returns:
        if the value for `key` for the given `Locale` is a `String`, return the `String` object; otherwise return `null`
      Since:
        1.4

    - #### getInt

          public int getInt(Object key)

      If the value of `key` is an `Integer` return its integer value, otherwise return 0.
      Parameters:
        `key` - the desired key
      Returns:
        if the value for `key` is an `Integer`, return its value, otherwise return 0

    - #### getInt

          public int getInt(Object key,
                            Locale l)

      If the value of `key` for the given `Locale` is an `Integer` return its integer value, otherwise return 0.
      Parameters:
        `key` - the desired key
        `l` - the desired locale
      Returns:
        if the value for `key` and `Locale` is an `Integer`, return its value, otherwise return 0
      Since:
        1.4

    - #### getBoolean

          public boolean getBoolean(Object key)

      If the value of `key` is boolean, return the boolean value, otherwise return false.
      Parameters:
        `key` - an `Object` specifying the key for the desired boolean value
      Returns:
        if the value of `key` is boolean, return the boolean value, otherwise return false.
      Since:
        1.4

    - #### getBoolean

          public boolean getBoolean(Object key,
                                    Locale l)

      If the value of `key` for the given `Locale` is boolean, return the boolean value, otherwise return false.
      Parameters:
        `key` - an `Object` specifying the key for the desired boolean value
        `l` - the desired locale
      Returns:
        if the value for `key` and `Locale` is boolean, return the boolean value, otherwise return false.
      Since:
        1.4

    - #### getInsets

          public Insets getInsets(Object key)

      If the value of `key` is an `Insets` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
      Returns:
        if the value for `key` is an `Insets`, return the `Insets` object; otherwise return `null`

    - #### getInsets

          public Insets getInsets(Object key,
                                  Locale l)

      If the value of `key` for the given `Locale` is an `Insets` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
        `l` - the desired locale
      Returns:
        if the value for `key` and `Locale` is an `Insets`, return the `Insets` object; otherwise return `null`
      Since:
        1.4

    - #### getDimension

          public Dimension getDimension(Object key)

      If the value of `key` is a `Dimension` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
      Returns:
        if the value for `key` is a `Dimension`, return the `Dimension` object; otherwise return `null`

    - #### getDimension

          public Dimension getDimension(Object key,
                                        Locale l)

      If the value of `key` for the given `Locale` is a `Dimension` return it, otherwise return `null`.
      Parameters:
        `key` - the desired key
        `l` - the desired locale
      Returns:
        if the value for `key` and `Locale` is a `Dimension`, return the `Dimension` object; otherwise return `null`
      Since:
        1.4

    - #### getUIClass

          public Class<? extends ComponentUI> getUIClass(String uiClassID,
                                                         ClassLoader uiClassLoader)

      The value of `get(uidClassID)` must be the `String` name of a class that implements the corresponding `ComponentUI` class. If the class hasn't been loaded before, this method looks up the class with `uiClassLoader.loadClass()` if a non `null` class loader is provided, `classForName()` otherwise.

      If a mapping for `uiClassID` exists or if the specified class can't be found, return `null`.

      This method is used by `getUI`, it's usually not necessary to call it directly.

      Parameters:
        `uiClassID` - a string containing the class ID
        `uiClassLoader` - the object which will load the class
      Returns:
        the value of `Class.forName(get(uidClassID))`
      See Also:
        `getUI(javax.swing.JComponent)`

    - #### getUIClass

          public Class<? extends ComponentUI> getUIClass(String uiClassID)

      Returns the L&F class that renders this component.
      Parameters:
        `uiClassID` - a string containing the class ID
      Returns:
        the Class object returned by `getUIClass(uiClassID, null)`

    - #### getUIError

          protected void getUIError(String msg)

      If `getUI()` fails for any reason, it calls this method before returning `null`. Subclasses may choose to do more or less here.
      Parameters:
        `msg` - message string to print
      See Also:
        `getUI(javax.swing.JComponent)`

    - #### getUI

          public ComponentUI getUI(JComponent target)

      Creates an `ComponentUI` implementation for the specified component. In other words create the look and feel specific delegate object for `target`. This is done in two steps:
      - Look up the name of the `ComponentUI` implementation class under the value returned by `target.getUIClassID()`.
      - Use the implementation classes static `createUI()` method to construct a look and feel delegate.
      Parameters:
        `target` - the `JComponent` which needs a UI
      Returns:
        the `ComponentUI` object

    - #### addPropertyChangeListener

          public void addPropertyChangeListener(PropertyChangeListener listener)

      Adds a `PropertyChangeListener` to the listener list. The listener is registered for all properties.

      A `PropertyChangeEvent` will get fired whenever a default is changed.

      Parameters:
        `listener` - the `PropertyChangeListener` to be added
      See Also:
        `PropertyChangeSupport`

    - #### removePropertyChangeListener

          public void removePropertyChangeListener(PropertyChangeListener listener)

      Removes a `PropertyChangeListener` from the listener list. This removes a `PropertyChangeListener` that was registered for all properties.
      Parameters:
        `listener` - the `PropertyChangeListener` to be removed
      See Also:
        `PropertyChangeSupport`

    - #### getPropertyChangeListeners

          public PropertyChangeListener[] getPropertyChangeListeners()

      Returns an array of all the `PropertyChangeListener`s added to this UIDefaults with addPropertyChangeListener().
      Returns:
        all of the `PropertyChangeListener`s added or an empty array if no listeners have been added
      Since:
        1.4

    - #### firePropertyChange

          protected void firePropertyChange(String propertyName,
                                            Object oldValue,
                                            Object newValue)

      Support for reporting bound property changes. If oldValue and newValue are not equal and the `PropertyChangeEvent`x listener list isn't empty, then fire a `PropertyChange` event to each listener.
      Parameters:
        `propertyName` - the programmatic name of the property that was changed
        `oldValue` - the old value of the property
        `newValue` - the new value of the property
      See Also:
        `PropertyChangeSupport`

    - #### addResourceBundle

          public void addResourceBundle(String bundleName)

      Adds a resource bundle to the list of resource bundles that are searched for localized values. Resource bundles are searched in the reverse order they were added. In other words, the most recently added bundle is searched first.
      Parameters:
        `bundleName` - the base name of the resource bundle to be added
      Since:
        1.4
      See Also:
        `ResourceBundle`, `removeResourceBundle(java.lang.String)`

    - #### removeResourceBundle

          public void removeResourceBundle(String bundleName)

      Removes a resource bundle from the list of resource bundles that are searched for localized defaults.
      Parameters:
        `bundleName` - the base name of the resource bundle to be removed
      Since:
        1.4
      See Also:
        `ResourceBundle`, `addResourceBundle(java.lang.String)`

    - #### setDefaultLocale

          public void setDefaultLocale(Locale l)

      Sets the default locale. The default locale is used in retrieving localized values via `get` methods that do not take a locale argument. As of release 1.4, Swing UI objects should retrieve localized values using the locale of their component rather than the default locale. The default locale exists to provide compatibility with pre 1.4 behaviour.
      Parameters:
        `l` - the new default locale
      Since:
        1.4
      See Also:
        `getDefaultLocale()`, `get(Object)`, `get(Object,Locale)`

    - #### getDefaultLocale

          public Locale getDefaultLocale()

      Returns the default locale. The default locale is used in retrieving localized values via `get` methods that do not take a locale argument. As of release 1.4, Swing UI objects should retrieve localized values using the locale of their component rather than the default locale. The default locale exists to provide compatibility with pre 1.4 behaviour.
      Returns:
        the default locale
      Since:
        1.4
      See Also:
        `setDefaultLocale(java.util.Locale)`, `get(Object)`, `get(Object,Locale)`

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