javax.swing
Class SpinnerListModel

java.lang.Object
  extended by javax.swing.AbstractSpinnerModel
      extended by javax.swing.SpinnerListModel
All Implemented Interfaces:
Serializable, SpinnerModel

public class SpinnerListModel
extends AbstractSpinnerModel
implements Serializable

An implementation of SpinnerModel which uses the values contained within a list or an array. The backing list or array is only stored as a reference within the class. As a result, changes made elsewhere to the members of the list or array are reflected by this model.

The model itself inherits a list of ChangeListeners from AbstractSpinnerModel. As this code is unaware of changes made to the backing list or array, it is the responsibility of the application using the model to invoke fireStateChanged(), in order to notify any ChangeListeners, when the list or array changes. The model handles notification when the reference itself is changed via setList() or when the current value is set directly using setValue().

Since:
1.4
See Also:
SpinnerModel, AbstractSpinnerModel, JSpinner, Serialized Form

Field Summary
 
Fields inherited from class javax.swing.AbstractSpinnerModel
listenerList
 
Constructor Summary
SpinnerListModel()
          Constructs a default SpinnerListModel.
SpinnerListModel(List<?> list)
          Constructs a SpinnerListModel using the supplied list.
SpinnerListModel(Object[] array)
          Constructs a SpinnerListModel using the supplied array.
 
Method Summary
 List<?> getList()
          Returns the backing list for this model.
 Object getNextValue()
          Returns the next value from the list, which is the same as the element stored at the current index + 1.
 Object getPreviousValue()
          Returns the previous value from the list, which is the same as the element stored at the current index - 1.
 Object getValue()
          Returns the current value of the model.
 void setList(List<?> list)
          Changes the backing list for this model.
 void setValue(Object value)
          Sets the current value of the model to be the one supplied.
 
Methods inherited from class javax.swing.AbstractSpinnerModel
addChangeListener, fireStateChanged, getChangeListeners, getListeners, removeChangeListener
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

SpinnerListModel

public SpinnerListModel()
Constructs a default SpinnerListModel. This is a model backed by a list containing only the single String element, "empty".


SpinnerListModel

public SpinnerListModel(List<?> list)
Constructs a SpinnerListModel using the supplied list. The model maintains a reference to this list, and returns consecutive elements in response to calls to getNextValue(). The initial value is that at position 0, so an initial call to getValue() returns the same as list.get(0).

Parameters:
list - The list to use for this model.
Throws:
IllegalArgumentException - if the list is null or contains no elements.
See Also:
getNextValue(), getValue()

SpinnerListModel

public SpinnerListModel(Object[] array)
Constructs a SpinnerListModel using the supplied array. The model stores a reference to the wrapper list returned by Arrays.asList(). The wrapper list reflects modifications in the underlying array, so these changes will also be reflected by the model. The model produces consecutive elements from the array in response to calls to getNextValue(). The initial value returned by getValue() is the same as array[0].

Parameters:
array - The array to use for this model.
Throws:
IllegalArgumentException - if the array is null or contains no elements.
See Also:
Arrays.asList(Object[]), getNextValue(), getValue()
Method Detail

getList

public List<?> getList()
Returns the backing list for this model.

Returns:
The backing list.

getNextValue

public Object getNextValue()
Returns the next value from the list, which is the same as the element stored at the current index + 1. Null is returned if there are no more values to be returned (the end of the list has been reached). An ambiguity can occur here, as null may also be returned as a valid list element. This operation does not change the current value.

Specified by:
getNextValue in interface SpinnerModel
Returns:
The next value from the list or null.

getPreviousValue

public Object getPreviousValue()
Returns the previous value from the list, which is the same as the element stored at the current index - 1. Null is returned if there are no more values to be returned (the start of the list has been reached). An ambiguity can occur here, as null may also be returned as a valid list element. This operation does not change the current value.

Specified by:
getPreviousValue in interface SpinnerModel
Returns:
The previous value from the list or null.

getValue

public Object getValue()
Returns the current value of the model. Initially, this will be the element at position 0. On later invocations, this will be the last element returned by getNextValue() or getPreviousValue().

Specified by:
getValue in interface SpinnerModel
Returns:
The current value.
See Also:
getPreviousValue(), getNextValue()

setList

public void setList(List<?> list)
Changes the backing list for this model. The model only stores a reference to the list, so any changes made to the list elsewhere will be reflected in the values returned by the model. A ChangeEvent is fired if the list being used actually changes (i.e. the new list is not referentially equal (!=) to the old one).

Parameters:
list - The new list to use.
Throws:
IllegalArgumentException - if the list is null or contains no elements.
See Also:
ChangeEvent

setValue

public void setValue(Object value)
Sets the current value of the model to be the one supplied. The value must exist within the backing list in order for the change to take place. Otherwise, an exception is thrown. The value used is the first occurrence of the value within the backing list. Listeners are notified of this change. Following the change, getNextValue() and getPreviousValue() return the objects following and prior to the supplied value, respectively.

Specified by:
setValue in interface SpinnerModel
Parameters:
value - The requested new value of the list.
Throws:
IllegalArgumentException - if the supplied value does not exist in the backing list.
See Also:
getPreviousValue(), getNextValue()