javax.swing

## Class JSplitPane

- java.lang.Object
- - java.awt.Component
  - - java.awt.Container
    - - javax.swing.JComponent
      - - javax.swing.JSplitPane

- All Implemented Interfaces:
    ImageObserver, MenuContainer, Serializable, Accessible

      public class JSplitPane
      extends JComponent
      implements Accessible

  `JSplitPane` is used to divide two (and only two) `Component`s. The two `Component`s are graphically divided based on the look and feel implementation, and the two `Component`s can then be interactively resized by the user. Information on using `JSplitPane` is in How to Use Split Panes in The Java Tutorial.

  The two `Component`s in a split pane can be aligned left to right using `JSplitPane.HORIZONTAL_SPLIT`, or top to bottom using `JSplitPane.VERTICAL_SPLIT`. The preferred way to change the size of the `Component`s is to invoke `setDividerLocation` where `location` is either the new x or y position, depending on the orientation of the `JSplitPane`.

  To resize the `Component`s to their preferred sizes invoke `resetToPreferredSizes`.

  When the user is resizing the `Component`s the minimum size of the `Components` is used to determine the maximum/minimum position the `Component`s can be set to. If the minimum size of the two components is greater than the size of the split pane the divider will not allow you to resize it. To alter the minimum size of a `JComponent`, see `JComponent.setMinimumSize(java.awt.Dimension)`.

  When the user resizes the split pane the new space is distributed between the two components based on the `resizeWeight` property. A value of 0, the default, indicates the right/bottom component gets all the space, where as a value of 1 indicates the left/top component gets all the space.

  Warning: Swing is not thread safe. For more information see Swing's Threading Policy.

  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 `XMLEncoder`.

  See Also:
    `setDividerLocation(double)`, `resetToPreferredSizes()`

- - ### Nested Class Summary

    Nested Classes
    Modifier and Type | Class and Description
    --- | ---
    `protected class` | `JSplitPane.AccessibleJSplitPane` This class implements accessibility support for the `JSplitPane` class.

    - ### Nested classes/interfaces inherited from class javax.swing.JComponent

      `JComponent.AccessibleJComponent`

    - ### Nested classes/interfaces inherited from class java.awt.Container

      `Container.AccessibleAWTContainer`

    - ### Nested classes/interfaces inherited from class java.awt.Component

      `Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy`

  - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `static String` | `BOTTOM` Used to add a `Component` below the other `Component`.
    `static String` | `CONTINUOUS_LAYOUT_PROPERTY` Bound property name for continuousLayout.
    `protected boolean` | `continuousLayout` Whether or not the views are continuously redisplayed while resizing.
    `static String` | `DIVIDER` Used to add a `Component` that will represent the divider.
    `static String` | `DIVIDER_LOCATION_PROPERTY` Bound property for the dividerLocation.
    `static String` | `DIVIDER_SIZE_PROPERTY` Bound property name for border.
    `protected int` | `dividerSize` Size of the divider.
    `static int` | `HORIZONTAL_SPLIT` Horizontal split indicates the `Component`s are split along the x axis.
    `static String` | `LAST_DIVIDER_LOCATION_PROPERTY` Bound property for lastLocation.
    `protected int` | `lastDividerLocation` Previous location of the split pane.
    `static String` | `LEFT` Used to add a `Component` to the left of the other `Component`.
    `protected Component` | `leftComponent` The left or top component.
    `static String` | `ONE_TOUCH_EXPANDABLE_PROPERTY` Bound property for oneTouchExpandable.
    `protected boolean` | `oneTouchExpandable` Is a little widget provided to quickly expand/collapse the split pane?
    `protected int` | `orientation` How the views are split.
    `static String` | `ORIENTATION_PROPERTY` Bound property name for orientation (horizontal or vertical).
    `static String` | `RESIZE_WEIGHT_PROPERTY` Bound property for weight.
    `static String` | `RIGHT` Used to add a `Component` to the right of the other `Component`.
    `protected Component` | `rightComponent` The right or bottom component.
    `static String` | `TOP` Used to add a `Component` above the other `Component`.
    `static int` | `VERTICAL_SPLIT` Vertical split indicates the `Component`s are split along the y axis.

    - ### Fields inherited from class javax.swing.JComponent

      `accessibleContext, listenerList, TOOL_TIP_TEXT_KEY, ui, UNDEFINED_CONDITION, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW`

    - ### Fields inherited from class java.awt.Component

      `BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT`

    - ### Fields inherited from interface java.awt.image.ImageObserver

      `ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `JSplitPane()` Creates a new `JSplitPane` configured to arrange the child components side-by-side horizontally, using two buttons for the components.
    `JSplitPane(int newOrientation)` Creates a new `JSplitPane` configured with the specified orientation.
    `JSplitPane(int newOrientation, boolean newContinuousLayout)` Creates a new `JSplitPane` with the specified orientation and redrawing style.
    `JSplitPane(int newOrientation, boolean newContinuousLayout, Component newLeftComponent, Component newRightComponent)` Creates a new `JSplitPane` with the specified orientation and redrawing style, and with the specified components.
    `JSplitPane(int newOrientation, Component newLeftComponent, Component newRightComponent)` Creates a new `JSplitPane` with the specified orientation and the specified components.

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `protected void` | `addImpl(Component comp, Object constraints, int index)` Adds the specified component to this split pane.
    `AccessibleContext` | `getAccessibleContext()` Gets the AccessibleContext associated with this JSplitPane.
    `Component` | `getBottomComponent()` Returns the component below, or to the right of the divider.
    `int` | `getDividerLocation()` Returns the last value passed to `setDividerLocation`.
    `int` | `getDividerSize()` Returns the size of the divider.
    `int` | `getLastDividerLocation()` Returns the last location the divider was at.
    `Component` | `getLeftComponent()` Returns the component to the left (or above) the divider.
    `int` | `getMaximumDividerLocation()` Returns the maximum location of the divider from the look and feel implementation.
    `int` | `getMinimumDividerLocation()` Returns the minimum location of the divider from the look and feel implementation.
    `int` | `getOrientation()` Returns the orientation.
    `double` | `getResizeWeight()` Returns the number that determines how extra space is distributed.
    `Component` | `getRightComponent()` Returns the component to the right (or below) the divider.
    `Component` | `getTopComponent()` Returns the component above, or to the left of the divider.
    `SplitPaneUI` | `getUI()` Returns the `SplitPaneUI` that is providing the current look and feel.
    `String` | `getUIClassID()` Returns the name of the L&F class that renders this component.
    `boolean` | `isContinuousLayout()` Gets the `continuousLayout` property.
    `boolean` | `isOneTouchExpandable()` Gets the `oneTouchExpandable` property.
    `boolean` | `isValidateRoot()` Returns true, so that calls to `revalidate` on any descendant of this `JSplitPane` will cause a request to be queued that will validate the `JSplitPane` and all its descendants.
    `protected void` | `paintChildren(Graphics g)` Subclassed to message the UI with `finishedPaintingChildren` after super has been messaged, as well as painting the border.
    `protected String` | `paramString()` Returns a string representation of this `JSplitPane`.
    `void` | `remove(Component component)` Removes the child component, `component` from the pane.
    `void` | `remove(int index)` Removes the `Component` at the specified index.
    `void` | `removeAll()` Removes all the child components from the split pane.
    `void` | `resetToPreferredSizes()` Lays out the `JSplitPane` layout based on the preferred size of the children components.
    `void` | `setBottomComponent(Component comp)` Sets the component below, or to the right of the divider.
    `void` | `setContinuousLayout(boolean newContinuousLayout)` Sets the value of the `continuousLayout` property, which must be `true` for the child components to be continuously redisplayed and laid out during user intervention.
    `void` | `setDividerLocation(double proportionalLocation)` Sets the divider location as a percentage of the `JSplitPane`'s size.
    `void` | `setDividerLocation(int location)` Sets the location of the divider.
    `void` | `setDividerSize(int newSize)` Sets the size of the divider.
    `void` | `setLastDividerLocation(int newLastLocation)` Sets the last location the divider was at to `newLastLocation`.
    `void` | `setLeftComponent(Component comp)` Sets the component to the left (or above) the divider.
    `void` | `setOneTouchExpandable(boolean newValue)` Sets the value of the `oneTouchExpandable` property, which must be `true` for the `JSplitPane` to provide a UI widget on the divider to quickly expand/collapse the divider.
    `void` | `setOrientation(int orientation)` Sets the orientation, or how the splitter is divided.
    `void` | `setResizeWeight(double value)` Specifies how to distribute extra space when the size of the split pane changes.
    `void` | `setRightComponent(Component comp)` Sets the component to the right (or below) the divider.
    `void` | `setTopComponent(Component comp)` Sets the component above, or to the left of the divider.
    `void` | `setUI(SplitPaneUI ui)` Sets the L&F object that renders this component.
    `void` | `updateUI()` Notification from the `UIManager` that the L&F has changed.

    - ### Methods inherited from class javax.swing.JComponent

      `addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBaseline, getBaselineResizeBehavior, getBorder, getBounds, getClientProperty, getComponentGraphics, getComponentPopupMenu, getConditionForKeyStroke, getDebugGraphicsOptions, getDefaultLocale, getFontMetrics, getGraphics, getHeight, getInheritsPopupMenu, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPopupLocation, getPreferredSize, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, hide, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingOrigin, isPaintingTile, isRequestFocusEnabled, paint, paintBorder, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setFont, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, update`

    - ### Methods inherited from class java.awt.Container

      `add, add, add, add, add, addContainerListener, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, getMousePosition, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, transferFocusDownCycle, validate, validateTree`

    - ### Methods inherited from class java.awt.Component

      `action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, createImage, createImage, createVolatileImage, createVolatileImage, disableEvents, dispatchEvent, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle`

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

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

- - ### Field Detail

    - #### VERTICAL_SPLIT

          public static final int VERTICAL_SPLIT

      Vertical split indicates the `Component`s are split along the y axis. For example the two `Component`s will be split one on top of the other.
      See Also:
        Constant Field Values

    - #### HORIZONTAL_SPLIT

          public static final int HORIZONTAL_SPLIT

      Horizontal split indicates the `Component`s are split along the x axis. For example the two `Component`s will be split one to the left of the other.
      See Also:
        Constant Field Values

    - #### LEFT

          public static final String LEFT

      Used to add a `Component` to the left of the other `Component`.
      See Also:
        Constant Field Values

    - #### RIGHT

          public static final String RIGHT

      Used to add a `Component` to the right of the other `Component`.
      See Also:
        Constant Field Values

    - #### TOP

          public static final String TOP

      Used to add a `Component` above the other `Component`.
      See Also:
        Constant Field Values

    - #### BOTTOM

          public static final String BOTTOM

      Used to add a `Component` below the other `Component`.
      See Also:
        Constant Field Values

    - #### DIVIDER

          public static final String DIVIDER

      Used to add a `Component` that will represent the divider.
      See Also:
        Constant Field Values

    - #### ORIENTATION_PROPERTY

          public static final String ORIENTATION_PROPERTY

      Bound property name for orientation (horizontal or vertical).
      See Also:
        Constant Field Values

    - #### CONTINUOUS_LAYOUT_PROPERTY

          public static final String CONTINUOUS_LAYOUT_PROPERTY

      Bound property name for continuousLayout.
      See Also:
        Constant Field Values

    - #### DIVIDER_SIZE_PROPERTY

          public static final String DIVIDER_SIZE_PROPERTY

      Bound property name for border.
      See Also:
        Constant Field Values

    - #### ONE_TOUCH_EXPANDABLE_PROPERTY

          public static final String ONE_TOUCH_EXPANDABLE_PROPERTY

      Bound property for oneTouchExpandable.
      See Also:
        Constant Field Values

    - #### LAST_DIVIDER_LOCATION_PROPERTY

          public static final String LAST_DIVIDER_LOCATION_PROPERTY

      Bound property for lastLocation.
      See Also:
        Constant Field Values

    - #### DIVIDER_LOCATION_PROPERTY

          public static final String DIVIDER_LOCATION_PROPERTY

      Bound property for the dividerLocation.
      Since:
        1.3
      See Also:
        Constant Field Values

    - #### RESIZE_WEIGHT_PROPERTY

          public static final String RESIZE_WEIGHT_PROPERTY

      Bound property for weight.
      Since:
        1.3
      See Also:
        Constant Field Values

    - #### orientation

          protected int orientation

      How the views are split.

    - #### continuousLayout

          protected boolean continuousLayout

      Whether or not the views are continuously redisplayed while resizing.

    - #### leftComponent

          protected Component leftComponent

      The left or top component.

    - #### rightComponent

          protected Component rightComponent

      The right or bottom component.

    - #### dividerSize

          protected int dividerSize

      Size of the divider.

    - #### oneTouchExpandable

          protected boolean oneTouchExpandable

      Is a little widget provided to quickly expand/collapse the split pane?

    - #### lastDividerLocation

          protected int lastDividerLocation

      Previous location of the split pane.

  - ### Constructor Detail

    - #### JSplitPane

          public JSplitPane()

      Creates a new `JSplitPane` configured to arrange the child components side-by-side horizontally, using two buttons for the components.

    - #### JSplitPane

          @ConstructorProperties(value="orientation")
          public JSplitPane(int newOrientation)

      Creates a new `JSplitPane` configured with the specified orientation.
      Parameters:
        `newOrientation` - `JSplitPane.HORIZONTAL_SPLIT` or `JSplitPane.VERTICAL_SPLIT`
      Throws:
        `IllegalArgumentException` - if `orientation` is not one of HORIZONTAL_SPLIT or VERTICAL_SPLIT.

    - #### JSplitPane

          public JSplitPane(int newOrientation,
                    boolean newContinuousLayout)

      Creates a new `JSplitPane` with the specified orientation and redrawing style.
      Parameters:
        `newOrientation` - `JSplitPane.HORIZONTAL_SPLIT` or `JSplitPane.VERTICAL_SPLIT`
        `newContinuousLayout` - a boolean, true for the components to redraw continuously as the divider changes position, false to wait until the divider position stops changing to redraw
      Throws:
        `IllegalArgumentException` - if `orientation` is not one of HORIZONTAL_SPLIT or VERTICAL_SPLIT

    - #### JSplitPane

          public JSplitPane(int newOrientation,
                    Component newLeftComponent,
                    Component newRightComponent)

      Creates a new `JSplitPane` with the specified orientation and the specified components.
      Parameters:
        `newOrientation` - `JSplitPane.HORIZONTAL_SPLIT` or `JSplitPane.VERTICAL_SPLIT`
        `newLeftComponent` - the `Component` that will appear on the left of a horizontally-split pane, or at the top of a vertically-split pane
        `newRightComponent` - the `Component` that will appear on the right of a horizontally-split pane, or at the bottom of a vertically-split pane
      Throws:
        `IllegalArgumentException` - if `orientation` is not one of: HORIZONTAL_SPLIT or VERTICAL_SPLIT

    - #### JSplitPane

          public JSplitPane(int newOrientation,
                    boolean newContinuousLayout,
                    Component newLeftComponent,
                    Component newRightComponent)

      Creates a new `JSplitPane` with the specified orientation and redrawing style, and with the specified components.
      Parameters:
        `newOrientation` - `JSplitPane.HORIZONTAL_SPLIT` or `JSplitPane.VERTICAL_SPLIT`
        `newContinuousLayout` - a boolean, true for the components to redraw continuously as the divider changes position, false to wait until the divider position stops changing to redraw
        `newLeftComponent` - the `Component` that will appear on the left of a horizontally-split pane, or at the top of a vertically-split pane
        `newRightComponent` - the `Component` that will appear on the right of a horizontally-split pane, or at the bottom of a vertically-split pane
      Throws:
        `IllegalArgumentException` - if `orientation` is not one of HORIZONTAL_SPLIT or VERTICAL_SPLIT

  - ### Method Detail

    - #### setUI

          public void setUI(SplitPaneUI ui)

      Sets the L&F object that renders this component.
      Parameters:
        `ui` - the `SplitPaneUI` L&F object
      See Also:
        `UIDefaults.getUI(javax.swing.JComponent)`

    - #### getUI

          public SplitPaneUI getUI()

      Returns the `SplitPaneUI` that is providing the current look and feel.
      Returns:
        the `SplitPaneUI` object that renders this component

    - #### updateUI

          public void updateUI()

      Notification from the `UIManager` that the L&F has changed. Replaces the current UI object with the latest version from the `UIManager`.
      Overrides:
        `updateUI` in class `JComponent`
      See Also:
        `JComponent.updateUI()`

    - #### getUIClassID

          public String getUIClassID()

      Returns the name of the L&F class that renders this component.
      Overrides:
        `getUIClassID` in class `JComponent`
      Returns:
        the string "SplitPaneUI"
      See Also:
        `JComponent.getUIClassID()`, `UIDefaults.getUI(javax.swing.JComponent)`

    - #### setDividerSize

          public void setDividerSize(int newSize)

      Sets the size of the divider.
      Parameters:
        `newSize` - an integer giving the size of the divider in pixels

    - #### getDividerSize

          public int getDividerSize()

      Returns the size of the divider.
      Returns:
        an integer giving the size of the divider in pixels

    - #### setLeftComponent

          public void setLeftComponent(Component comp)

      Sets the component to the left (or above) the divider.
      Parameters:
        `comp` - the `Component` to display in that position

    - #### getLeftComponent

          public Component getLeftComponent()

      Returns the component to the left (or above) the divider.
      Returns:
        the `Component` displayed in that position

    - #### setTopComponent

          public void setTopComponent(Component comp)

      Sets the component above, or to the left of the divider.
      Parameters:
        `comp` - the `Component` to display in that position

    - #### getTopComponent

          public Component getTopComponent()

      Returns the component above, or to the left of the divider.
      Returns:
        the `Component` displayed in that position

    - #### setRightComponent

          public void setRightComponent(Component comp)

      Sets the component to the right (or below) the divider.
      Parameters:
        `comp` - the `Component` to display in that position

    - #### getRightComponent

          public Component getRightComponent()

      Returns the component to the right (or below) the divider.
      Returns:
        the `Component` displayed in that position

    - #### setBottomComponent

          public void setBottomComponent(Component comp)

      Sets the component below, or to the right of the divider.
      Parameters:
        `comp` - the `Component` to display in that position

    - #### getBottomComponent

          public Component getBottomComponent()

      Returns the component below, or to the right of the divider.
      Returns:
        the `Component` displayed in that position

    - #### setOneTouchExpandable

          public void setOneTouchExpandable(boolean newValue)

      Sets the value of the `oneTouchExpandable` property, which must be `true` for the `JSplitPane` to provide a UI widget on the divider to quickly expand/collapse the divider. The default value of this property is `false`. Some look and feels might not support one-touch expanding; they will ignore this property.
      Parameters:
        `newValue` - `true` to specify that the split pane should provide a collapse/expand widget
      See Also:
        `isOneTouchExpandable()`

    - #### isOneTouchExpandable

          public boolean isOneTouchExpandable()

      Gets the `oneTouchExpandable` property.
      Returns:
        the value of the `oneTouchExpandable` property
      See Also:
        `setOneTouchExpandable(boolean)`

    - #### setLastDividerLocation

          public void setLastDividerLocation(int newLastLocation)

      Sets the last location the divider was at to `newLastLocation`.
      Parameters:
        `newLastLocation` - an integer specifying the last divider location in pixels, from the left (or upper) edge of the pane to the left (or upper) edge of the divider

    - #### getLastDividerLocation

          public int getLastDividerLocation()

      Returns the last location the divider was at.
      Returns:
        an integer specifying the last divider location as a count of pixels from the left (or upper) edge of the pane to the left (or upper) edge of the divider

    - #### setOrientation

          public void setOrientation(int orientation)

      Sets the orientation, or how the splitter is divided. The options are:
      - JSplitPane.VERTICAL_SPLIT (above/below orientation of components)
      - JSplitPane.HORIZONTAL_SPLIT (left/right orientation of components)
      Parameters:
        `orientation` - an integer specifying the orientation
      Throws:
        `IllegalArgumentException` - if orientation is not one of: HORIZONTAL_SPLIT or VERTICAL_SPLIT.

    - #### getOrientation

          public int getOrientation()

      Returns the orientation.
      Returns:
        an integer giving the orientation
      See Also:
        `setOrientation(int)`

    - #### setContinuousLayout

          public void setContinuousLayout(boolean newContinuousLayout)

      Sets the value of the `continuousLayout` property, which must be `true` for the child components to be continuously redisplayed and laid out during user intervention. The default value of this property is look and feel dependent. Some look and feels might not support continuous layout; they will ignore this property.
      Parameters:
        `newContinuousLayout` - `true` if the components should continuously be redrawn as the divider changes position
      See Also:
        `isContinuousLayout()`

    - #### isContinuousLayout

          public boolean isContinuousLayout()

      Gets the `continuousLayout` property.
      Returns:
        the value of the `continuousLayout` property
      See Also:
        `setContinuousLayout(boolean)`

    - #### setResizeWeight

          public void setResizeWeight(double value)

      Specifies how to distribute extra space when the size of the split pane changes. A value of 0, the default, indicates the right/bottom component gets all the extra space (the left/top component acts fixed), where as a value of 1 specifies the left/top component gets all the extra space (the right/bottom component acts fixed). Specifically, the left/top component gets (weight * diff) extra space and the right/bottom component gets (1 - weight) * diff extra space.
      Parameters:
        `value` - as described above
      Throws:
        `IllegalArgumentException` - if `value` is < 0 or > 1
      Since:
        1.3

    - #### getResizeWeight

          public double getResizeWeight()

      Returns the number that determines how extra space is distributed.
      Returns:
        how extra space is to be distributed on a resize of the split pane
      Since:
        1.3

    - #### resetToPreferredSizes

          public void resetToPreferredSizes()

      Lays out the `JSplitPane` layout based on the preferred size of the children components. This will likely result in changing the divider location.

    - #### setDividerLocation

          public void setDividerLocation(double proportionalLocation)

      Sets the divider location as a percentage of the `JSplitPane`'s size.

      This method is implemented in terms of `setDividerLocation(int)`. This method immediately changes the size of the split pane based on its current size. If the split pane is not correctly realized and on screen, this method will have no effect (new divider location will become (current size * proportionalLocation) which is 0).

      Parameters:
        `proportionalLocation` - a double-precision floating point value that specifies a percentage, from zero (top/left) to 1.0 (bottom/right)
      Throws:
        `IllegalArgumentException` - if the specified location is < 0 or > 1.0

    - #### setDividerLocation

          public void setDividerLocation(int location)

      Sets the location of the divider. This is passed off to the look and feel implementation, and then listeners are notified. A value less than 0 implies the divider should be reset to a value that attempts to honor the preferred size of the left/top component. After notifying the listeners, the last divider location is updated, via `setLastDividerLocation`.
      Parameters:
        `location` - an int specifying a UI-specific value (typically a pixel count)

    - #### getDividerLocation

          public int getDividerLocation()

      Returns the last value passed to `setDividerLocation`. The value returned from this method may differ from the actual divider location (if `setDividerLocation` was passed a value bigger than the current size).
      Returns:
        an integer specifying the location of the divider

    - #### getMinimumDividerLocation

          public int getMinimumDividerLocation()

      Returns the minimum location of the divider from the look and feel implementation.
      Returns:
        an integer specifying a UI-specific value for the minimum location (typically a pixel count); or -1 if the UI is `null`

    - #### getMaximumDividerLocation

          public int getMaximumDividerLocation()

      Returns the maximum location of the divider from the look and feel implementation.
      Returns:
        an integer specifying a UI-specific value for the maximum location (typically a pixel count); or -1 if the UI is `null`

    - #### remove

          public void remove(Component component)

      Removes the child component, `component` from the pane. Resets the `leftComponent` or `rightComponent` instance variable, as necessary.
      Overrides:
        `remove` in class `Container`
      Parameters:
        `component` - the `Component` to remove
      See Also:
        `Container.add(java.awt.Component)`, `Container.invalidate()`, `Container.validate()`, `Container.remove(int)`

    - #### remove

          public void remove(int index)

      Removes the `Component` at the specified index. Updates the `leftComponent` and `rightComponent` instance variables as necessary, and then messages super.
      Overrides:
        `remove` in class `Container`
      Parameters:
        `index` - an integer specifying the component to remove, where 1 specifies the left/top component and 2 specifies the bottom/right component
      See Also:
        `Container.add(java.awt.Component)`, `Container.invalidate()`, `Container.validate()`, `Container.getComponentCount()`

    - #### removeAll

          public void removeAll()

      Removes all the child components from the split pane. Resets the `leftComonent` and `rightComponent` instance variables.
      Overrides:
        `removeAll` in class `Container`
      See Also:
        `Container.add(java.awt.Component)`, `Container.remove(int)`, `Container.invalidate()`

    - #### isValidateRoot

          public boolean isValidateRoot()

      Returns true, so that calls to `revalidate` on any descendant of this `JSplitPane` will cause a request to be queued that will validate the `JSplitPane` and all its descendants.
      Overrides:
        `isValidateRoot` in class `JComponent`
      Returns:
        true
      See Also:
        `JComponent.revalidate()`, `Container.isValidateRoot()`

    - #### addImpl

          protected void addImpl(Component comp,
                     Object constraints,
                     int index)

      Adds the specified component to this split pane. If `constraints` identifies the left/top or right/bottom child component, and a component with that identifier was previously added, it will be removed and then `comp` will be added in its place. If `constraints` is not one of the known identifiers the layout manager may throw an `IllegalArgumentException`.

      The possible constraints objects (Strings) are:

      - JSplitPane.TOP
      - JSplitPane.LEFT
      - JSplitPane.BOTTOM
      - JSplitPane.RIGHT
      If the `constraints` object is `null`, the component is added in the first available position (left/top if open, else right/bottom).
      Overrides:
        `addImpl` in class `Container`
      Parameters:
        `comp` - the component to add
        `constraints` - an `Object` specifying the layout constraints (position) for this component
        `index` - an integer specifying the index in the container's list.
      Throws:
        `IllegalArgumentException` - if the `constraints` object does not match an existing component
      See Also:
        `Container.addImpl(Component, Object, int)`

    - #### paintChildren

          protected void paintChildren(Graphics g)

      Subclassed to message the UI with `finishedPaintingChildren` after super has been messaged, as well as painting the border.
      Overrides:
        `paintChildren` in class `JComponent`
      Parameters:
        `g` - the `Graphics` context within which to paint
      See Also:
        `JComponent.paint(java.awt.Graphics)`, `Container.paint(java.awt.Graphics)`

    - #### paramString

          protected String paramString()

      Returns a string representation of this `JSplitPane`. This method is intended to be used only for debugging purposes, and the content and format of the returned string may vary between implementations. The returned string may be empty but may not be `null`.
      Overrides:
        `paramString` in class `JComponent`
      Returns:
        a string representation of this `JSplitPane`.

    - #### getAccessibleContext

          public AccessibleContext getAccessibleContext()

      Gets the AccessibleContext associated with this JSplitPane. For split panes, the AccessibleContext takes the form of an AccessibleJSplitPane. A new AccessibleJSplitPane instance is created if necessary.
      Specified by:
        `getAccessibleContext` in interface `Accessible`
      Overrides:
        `getAccessibleContext` in class `JComponent`
      Returns:
        an AccessibleJSplitPane that serves as the AccessibleContext of this JSplitPane

Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2019, Oracle and/or its affiliates. All rights reserved.