How to use

updateForwardFunction

method

in

ca.odell.glazedlists.FunctionList

/**
 * Construct a {@link FunctionList} which stores the result of transforming
 * each source element using the given forward {@link Function}. If the
 * reverse {@link Function} is not null, {@link #add(Object)},
 * {@link #add(int, Object)} and {@link #set(int, Object)} will execute
 * as expected.
 *
 * <p> Note: an {@link AdvancedFunction} can be specified for the forward
 * {@link Function} which allows the implementor a chance to examine the
 * prior value that was mapped to a source element when it must be remapped
 * due to a modification (from a call to {@link List#set}).
 *
 * @param source the EventList to decorate with a function transformation
 * @param forward the function to execute on each source element
 * @param reverse the function to map elements of FunctionList back to
 *      element values in the source list
 */
public FunctionList(EventList<S> source, Function<S,E> forward, Function<E,S> reverse) {
  super(source);
  updateForwardFunction(forward);
  setReverseFunction(reverse);
  // save a reference to the source elements
  this.sourceElements = new ArrayList<S>(source);
  // map all of the elements within source
  this.mappedElements = new ArrayList<E>(source.size());
  for (int i = 0, n = source.size(); i < n; i++) {
    this.mappedElements.add(forward(source.get(i)));
  }
  source.addListEventListener(this);
}

/**
 * Construct a {@link FunctionList} which stores the result of transforming
 * each source element using the given forward {@link Function}. If the
 * reverse {@link Function} is not null, {@link #add(Object)},
 * {@link #add(int, Object)} and {@link #set(int, Object)} will execute
 * as expected.
 *
 * <p> Note: an {@link AdvancedFunction} can be specified for the forward
 * {@link Function} which allows the implementor a chance to examine the
 * prior value that was mapped to a source element when it must be remapped
 * due to a modification (from a call to {@link List#set}).
 *
 * @param source the EventList to decorate with a function transformation
 * @param forward the function to execute on each source element
 * @param reverse the function to map elements of FunctionList back to
 *      element values in the source list
 */
public FunctionList(EventList<S> source, Function<S,E> forward, Function<E,S> reverse) {
  super(source);
  updateForwardFunction(forward);
  setReverseFunction(reverse);
  // save a reference to the source elements
  this.sourceElements = new ArrayList<S>(source);
  // map all of the elements within source
  this.mappedElements = new ArrayList<E>(source.size());
  for (int i = 0, n = source.size(); i < n; i++) {
    this.mappedElements.add(forward(source.get(i)));
  }
  source.addListEventListener(this);
}

/**
 * Construct a {@link FunctionList} which stores the result of transforming
 * each source element using the given forward {@link Function}. If the
 * reverse {@link Function} is not null, {@link #add(Object)},
 * {@link #add(int, Object)} and {@link #set(int, Object)} will execute
 * as expected.
 *
 * <p> Note: an {@link AdvancedFunction} can be specified for the forward
 * {@link Function} which allows the implementor a chance to examine the
 * prior value that was mapped to a source element when it must be remapped
 * due to a modification (from a call to {@link List#set}).
 *
 * @param source the EventList to decorate with a function transformation
 * @param forward the function to execute on each source element
 * @param reverse the function to map elements of FunctionList back to
 *      element values in the source list
 */
public FunctionList(EventList<S> source, Function<S,E> forward, Function<E,S> reverse) {
  super(source);
  updateForwardFunction(forward);
  setReverseFunction(reverse);
  // save a reference to the source elements
  this.sourceElements = new ArrayList<S>(source);
  // map all of the elements within source
  this.mappedElements = new ArrayList<E>(source.size());
  for (int i = 0, n = source.size(); i < n; i++) {
    this.mappedElements.add(forward(source.get(i)));
  }
  source.addListEventListener(this);
}

/**
 * Changes the {@link Function} that evaluates source elements to produce
 * mapped elements. Calling this method with a different
 * <code>forward</code> Function will cause all elements in this
 * FunctionList to be reevaluated.
 *
 * <p>Callers of this method typically also want to update the reverse
 * function using {@link #setReverseFunction} if one exists.
 */
public void setForwardFunction(Function<S,E> forward) {
  updateForwardFunction(forward);
  updates.beginEvent(true);
  // remap all of the elements within source
  for (int i = 0, n = source.size(); i < n; i++) {
    final E oldValue = this.mappedElements.set(i, forward(source.get(i)));
    updates.elementUpdated(i, oldValue);
  }
  updates.commitEvent();
}

/**
 * Changes the {@link Function} that evaluates source elements to produce
 * mapped elements. Calling this method with a different
 * <code>forward</code> Function will cause all elements in this
 * FunctionList to be reevaluated.
 *
 * <p>Callers of this method typically also want to update the reverse
 * function using {@link #setReverseFunction} if one exists.
 */
public void setForwardFunction(Function<S,E> forward) {
  updateForwardFunction(forward);
  updates.beginEvent(true);
  // remap all of the elements within source
  for (int i = 0, n = source.size(); i < n; i++) {
    final E oldValue = this.mappedElements.set(i, forward(source.get(i)));
    updates.elementUpdated(i, oldValue);
  }
  updates.commitEvent();
}

/**
 * Changes the {@link Function} that evaluates source elements to produce
 * mapped elements. Calling this method with a different
 * <code>forward</code> Function will cause all elements in this
 * FunctionList to be reevaluated.
 *
 * <p>Callers of this method typically also want to update the reverse
 * function using {@link #setReverseFunction} if one exists.
 */
public void setForwardFunction(Function<S,E> forward) {
  updateForwardFunction(forward);
  updates.beginEvent(true);
  // remap all of the elements within source
  for (int i = 0, n = source.size(); i < n; i++) {
    final E oldValue = this.mappedElements.set(i, forward(source.get(i)));
    updates.elementUpdated(i, oldValue);
  }
  updates.commitEvent();
}