| /******************************************************************************* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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. |
| *******************************************************************************/ |
| package org.ofbiz.base.util.collections; |
| |
| import java.util.Comparator; |
| import java.util.List; |
| import java.util.Map; |
| |
| import org.ofbiz.base.util.Debug; |
| import org.ofbiz.base.util.UtilGenerics; |
| |
| /** |
| * MapComparator.java |
| * |
| */ |
| public class MapComparator implements Comparator<Map<Object, Object>> { |
| |
| public static final String module = MapComparator.class.getName(); |
| |
| private List<? extends Object> keys; |
| |
| /** |
| * Method MapComparator. |
| * @param keys List of Map keys to sort on |
| */ |
| public MapComparator(List<? extends Object> keys) { |
| this.keys = keys; |
| } |
| |
| /** |
| * @see java.lang.Object#equals(java.lang.Object) |
| */ |
| @Override |
| public boolean equals(Object obj) { |
| return obj.equals(this); |
| } |
| |
| /** |
| * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object) |
| */ |
| public int compare(Map<Object, Object> map1, Map<Object, Object> map2) { |
| |
| if (keys == null || keys.size() < 1) { |
| throw new IllegalArgumentException("No sort fields defined"); |
| } |
| |
| for (Object key: keys) { |
| // if false will be descending, ie reverse order |
| boolean ascending = true; |
| |
| Object o1 = null; |
| Object o2 = null; |
| |
| if (key instanceof FlexibleMapAccessor<?>) { |
| FlexibleMapAccessor<Object> fmaKey = UtilGenerics.cast(key); |
| ascending = fmaKey.getIsAscending(); |
| |
| //Debug.logInfo("Doing compare with a FlexibleMapAccessor [" + fmaKey.getOriginalName() + "] ascending [" + ascending + "]", module); |
| |
| o1 = fmaKey.get(UtilGenerics.<String, Object>checkMap(map1)); |
| o2 = fmaKey.get(UtilGenerics.<String, Object>checkMap(map2)); |
| } else { |
| if (key instanceof String) { |
| String keyStr = (String) key; |
| if (keyStr.charAt(0) == '-') { |
| ascending = false; |
| key = keyStr.substring(1); |
| } else if (keyStr.charAt(0) == '+') { |
| ascending = true; |
| key = keyStr.substring(1); |
| } |
| } |
| |
| o1 = map1.get(key); |
| o2 = map2.get(key); |
| } |
| |
| if (o1 == null && o2 == null) { |
| continue; |
| } |
| |
| int compareResult = 0; |
| if (o1 != null && o2 == null) { |
| compareResult = -1; |
| } |
| if (o1 == null && o2 != null) { |
| compareResult = 1; |
| } |
| |
| if (compareResult == 0) { |
| try { |
| // the map values in question MUST implement the Comparable interface, if not we'll throw an exception |
| Comparable<Object> comp1 = UtilGenerics.cast(o1); |
| compareResult = comp1.compareTo(o2); |
| } catch (Exception e) { |
| String errorMessage = "Error sorting list of Maps: " + e.toString(); |
| Debug.logError(e, errorMessage, module); |
| throw new RuntimeException(errorMessage); |
| } |
| } |
| |
| // if zero they are equal, so we carry on to the next key to try and find a difference |
| if (compareResult != 0) { |
| if (ascending) { |
| return compareResult; |
| } else { |
| return -compareResult; |
| } |
| } |
| } |
| |
| // none of them were different, so they are equal |
| return 0; |
| } |
| } |