## javax.help
Class DefaultHelpHistoryModel

    java.lang.Object
      javax.help.DefaultHelpHistoryModel

All Implemented Interfaces:
  java.util.EventListener, HelpHistoryModel, HelpModelListener, java.io.Serializable

public class DefaultHelpHistoryModel
extends java.lang.Object
implements HelpHistoryModel

DefaultHelpHistoryModel is default implementation of HelpHistoryModel interface

See Also:
  Serialized Form

Constructor Summary
`DefaultHelpHistoryModel(JHelp help)` Creates new DefaultHelpHistoryModel for given JHelp

Method Summary
`void` `addHelpHistoryModelListener(HelpHistoryModelListener l)` Adds a listener for the HelpHistoryModelEvent posted after the model has changed.
`void` `discard()` Discards a history
`java.util.Vector` `getBackwardHistory()` Returns a backward history vector
`java.util.Vector` `getForwardHistory()` Returns a forward history vector
`java.util.Vector` `getHistory()` Returns a history
`int` `getIndex()` Returns a current history position
`void` `goBack()` Sets the previous histroy entry
`void` `goForward()` Sets the next history entry
`void` `idChanged(HelpModelEvent e)` Tells the listener that the current ID in the HelpModel has changed.
`void` `removeHelpHistoryModelListener(HelpHistoryModelListener l)` Removes a listener previously added with `addHelpHistoryModelListener`
`void` `removeHelpSet(HelpSet hs)` Removes entries related to removed HelpSet from history
`void` `removeLastEntry()` Removes the last history entry
`void` `setHelpModel(HelpModel model)` Sets a new HelpModel
`void` `setHistoryEntry(int index)` Sets the current history entry

Methods inherited from class java.lang.Object
`equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Constructor Detail

### DefaultHelpHistoryModel

    public DefaultHelpHistoryModel(JHelp help)

  Creates new DefaultHelpHistoryModel for given JHelp

Parameters:
  `help` - The JHelp

Method Detail

### setHelpModel

    public void setHelpModel(HelpModel model)

  Sets a new HelpModel

  Specified by:
    `setHelpModel` in interface `HelpHistoryModel`
  Parameters:
    `model` - The new HelpModel

### removeHelpHistoryModelListener

    public void removeHelpHistoryModelListener(HelpHistoryModelListener l)

  Removes a listener previously added with `addHelpHistoryModelListener`

  Specified by:
    `removeHelpHistoryModelListener` in interface `HelpHistoryModel`
  Parameters:
    `l` - The listener to remove.
  See Also:
    `HelpHistoryModel.addHelpHistoryModelListener(javax.help.event.HelpHistoryModelListener)`

### addHelpHistoryModelListener

    public void addHelpHistoryModelListener(HelpHistoryModelListener l)

  Adds a listener for the HelpHistoryModelEvent posted after the model has changed.

  Specified by:
    `addHelpHistoryModelListener` in interface `HelpHistoryModel`
  Parameters:
    `l` - The listener to add.
  See Also:
    `HelpHistoryModel.removeHelpHistoryModelListener(javax.help.event.HelpHistoryModelListener)`

### discard

    public void discard()

  Discards a history

  Specified by:
    `discard` in interface `HelpHistoryModel`

### getHistory

    public java.util.Vector getHistory()

  Returns a history

  Specified by:
    `getHistory` in interface `HelpHistoryModel`
  Returns:
    The vector of history entries

### removeLastEntry

    public void removeLastEntry()

  Removes the last history entry

### getIndex

    public int getIndex()

  Returns a current history position

  Specified by:
    `getIndex` in interface `HelpHistoryModel`
  Returns:
    The history index

### goForward

    public void goForward()

  Sets the next history entry

  Specified by:
    `goForward` in interface `HelpHistoryModel`

### goBack

    public void goBack()

  Sets the previous histroy entry

  Specified by:
    `goBack` in interface `HelpHistoryModel`

### getForwardHistory

    public java.util.Vector getForwardHistory()

  Returns a forward history vector

  Specified by:
    `getForwardHistory` in interface `HelpHistoryModel`
  Returns:
    The vector of forward history entries

### getBackwardHistory

    public java.util.Vector getBackwardHistory()

  Returns a backward history vector

  Specified by:
    `getBackwardHistory` in interface `HelpHistoryModel`
  Returns:
    The vector of backward history entries

### setHistoryEntry

    public void setHistoryEntry(int index)

  Sets the current history entry

  Specified by:
    `setHistoryEntry` in interface `HelpHistoryModel`
  Parameters:
    `index` - The index of history entry

### idChanged

    public void idChanged(HelpModelEvent e)

  Tells the listener that the current ID in the HelpModel has changed. All highlights from the previous location change at this point.

  Specified by:
    `idChanged` in interface `HelpModelListener`
  Parameters:
    `e` - The event

### removeHelpSet

    public void removeHelpSet(HelpSet hs)

  Removes entries related to removed HelpSet from history

  Specified by:
    `removeHelpSet` in interface `HelpHistoryModel`
  Parameters:
    `hs` - The removed HelpSet