Java tutorial
/* * (C) Copyright 2006-2007 Nuxeo SA (http://nuxeo.com/) and others. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * * Contributors: * Nuxeo - initial API and implementation * * $Id$ */ package org.nuxeo.ecm.platform.ui.web.component; import java.io.Serializable; import java.text.Collator; import java.util.Comparator; import java.util.Locale; import javax.faces.context.FacesContext; import javax.faces.model.SelectItem; import org.apache.commons.lang.StringUtils; /** * Orders select items by id or label, handling localization. * * @author <a href="mailto:glefter@nuxeo.com">George Lefter</a> */ public class SelectItemComparator implements Comparator<SelectItem>, Serializable { private static final long serialVersionUID = 1L; private final String[] ordering; private final Boolean caseSensitive; private final Collator collator; private final Locale locale; public SelectItemComparator(String ordering, Boolean caseSentitive, Locale locale) { this.ordering = StringUtils.split(ordering, ","); caseSensitive = caseSentitive; if (locale == null) { FacesContext context = FacesContext.getCurrentInstance(); this.locale = context.getViewRoot().getLocale(); } else { this.locale = locale; } collator = Collator.getInstance(this.locale); if (Boolean.TRUE.equals(caseSensitive)) { collator.setStrength(Collator.TERTIARY); // TERTIARY will make a // difference between 'a' // and 'A' } else { collator.setStrength(Collator.SECONDARY); } } public SelectItemComparator(String ordering, Boolean caseSensitive) { this(ordering, caseSensitive, null); } protected int compareField(String field, SelectItem item1, SelectItem item2) { if ("label".equals(field)) { String label1 = item1.getLabel(); String label2 = item2.getLabel(); return collator.compare(label1, label2); } else if ("id".equals(field)) { String value1 = String.valueOf(item1.getValue()); String value2 = String.valueOf(item2.getValue()); // TODO: maybe deal with numbers comparisons (?) return collator.compare(value1, value2); } else { throw new RuntimeException("Invalid sort criteria " + field); } } @Override public int compare(SelectItem item1, SelectItem item2) { for (String field : ordering) { int compare = compareField(field, item1, item2); if (compare != 0) { return compare; } } return 0; } }