edu.harvard.med.screensaver.ui.arch.util.UISelectOneBean.java Source code

Introduction

Here is the source code for edu.harvard.med.screensaver.ui.arch.util.UISelectOneBean.java

Source

// $HeadURL$
// $Id$
//
// Copyright  2006, 2010, 2011, 2012 by the President and Fellows of Harvard College.
//
// Screensaver is an open-source project developed by the ICCB-L and NSRB labs
// at Harvard Medical School. This software is distributed under the terms of
// the GNU General Public License.

package edu.harvard.med.screensaver.ui.arch.util;

import java.util.ArrayList;
import java.util.Collection;

import javax.faces.model.SelectItem;

import com.google.common.collect.Iterables;
import org.apache.log4j.Logger;

public class UISelectOneBean<T> extends UISelectBean<T> {
    // static members

    private static Logger log = Logger.getLogger(UISelectOneBean.class);

    // instance data members

    private T _selection;
    /** never null */
    private String _selectionKey = EMPTY_KEY;
    private int _selectionIndex;
    private T _defaultSelection;

    // public constructors and methods

    public UISelectOneBean() {
        this(new ArrayList<T>());
    }

    public UISelectOneBean(Collection<T> objects) {
        this(objects, false);
    }

    public UISelectOneBean(Collection<T> objects, boolean isEmptyValueAllowed) {
        this(objects, null, isEmptyValueAllowed);
    }

    public UISelectOneBean(Collection<T> objects, T defaultSelection) {
        this(objects, defaultSelection, false);
    }

    public UISelectOneBean(Collection<T> objects, T defaultSelection, boolean isEmptyValueAllowed) {
        super(objects, isEmptyValueAllowed);
        if (defaultSelection == null) {
            if (!_isEmptyValueAllowed) {
                if (objects.size() > 0) {
                    defaultSelection = objects.iterator().next();
                }
            }
        }
        _defaultSelection = defaultSelection;
        setSelection(_defaultSelection);
    }

    @Override
    final public void setDomain(Collection<T> objects) {
        setDomain(objects, objects.size() > 0 ? Iterables.get(objects, 0) : null);
    }

    public void setDomain(Collection<T> objects, T defaultSelection) {
        super.setDomain(objects);

        // HACK: deal with fact that _selectionKey is not set until parent
        // constructor returns, although this method is called before that!
        if (_selectionKey == null) {
            _selectionKey = EMPTY_KEY;
        }

        // set or restore selection
        if (objects.size() == 0) {
            _selection = null;
            _selectionKey = EMPTY_KEY;
            _selectionIndex = 0;
            _defaultSelection = null;
        } else {
            _defaultSelection = defaultSelection;
            if (!_key2Obj.containsKey(_selectionKey)) {
                setSelection(_defaultSelection);
            }
        }
    }

    /**
     * Change the selection by specifying a new selection key.
     */
    public void setKey(String newSelectionKey) {
        if (newSelectionKey == null) {
            newSelectionKey = EMPTY_KEY;
        }

        if (!_key2Obj.containsKey(newSelectionKey)) {
            // unknown selection key! (client code error) recover...
            return;
        }
        if (_selectionKey.equals(newSelectionKey)) {
            return;
        }

        _selectionKey = newSelectionKey;
        _selection = _key2Obj.get(newSelectionKey);
        int i = 0;
        for (SelectItem selectItem : getSelectItems()) {
            if (selectItem.getValue().equals(newSelectionKey)) {
                _selectionIndex = i;
                break;
            }
            ++i;
        }
        setChanged();
        notifyObservers(_selection);
    }

    public String getKey() {
        return _selectionKey;
    }

    /**
     * Alias for setKey(), to match naming convention of JSF "selectItems" "value"
     * attribute.
     */
    public void setValue(String newSelectionKey) {
        setKey(newSelectionKey);
    }

    /**
     * Alias for getKey(), to match naming convention of JSF "selectItems" "value"
     * attribute.
     */
    public String getValue() {
        return getKey();
    }

    /**
     * Change the selection by specifying a new selection object.
     */
    public void setSelection(T t) {
        setKey(_makeKey(t));
    }

    public T getSelection() {
        return _selection;
    }

    public T getDefaultSelection() {
        return _defaultSelection;
    }

    /**
     * Change the selection by specifying a new selection index.
     */
    public void setSelectionIndex(int index) {
        setSelection(_key2Obj.get(getSelectItems().get(index).getValue()));
    }

    public int getSelectionIndex() {
        return _selectionIndex;
    }

}