diff options
Diffstat (limited to 'gson/src/main/java/org/onap/policy/common/gson/DoubleConverter.java')
-rw-r--r-- | gson/src/main/java/org/onap/policy/common/gson/DoubleConverter.java | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/gson/src/main/java/org/onap/policy/common/gson/DoubleConverter.java b/gson/src/main/java/org/onap/policy/common/gson/DoubleConverter.java new file mode 100644 index 00000000..81803ff2 --- /dev/null +++ b/gson/src/main/java/org/onap/policy/common/gson/DoubleConverter.java @@ -0,0 +1,117 @@ +/* + * ============LICENSE_START======================================================= + * ONAP + * ================================================================================ + * Copyright (C) 2019 AT&T Intellectual Property. All rights reserved. + * ================================================================================ + * 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. + * ============LICENSE_END========================================================= + */ + +package org.onap.policy.common.gson; + +import java.util.ArrayList; +import java.util.List; +import java.util.Map; +import java.util.Map.Entry; +import java.util.Set; + +/** + * Converter for Double values. By default, GSON treats all Objects that are numbers, as + * Double. This converts Doubles to Integer or Long, if possible. It converts stand-alone + * Doubles, as well as those found within Arrays and Maps. + */ +public class DoubleConverter { + + private DoubleConverter() { + // do nothing + } + + /** + * Performs in-place conversion of all values in a list. + * + * @param list the list whose values are to be converted + */ + public static void convertFromDouble(List<Object> list) { + if (list == null) { + return; + } + + List<Object> original = new ArrayList<>(list); + + list.clear(); + original.forEach(item -> list.add(convertFromDouble(item))); + } + + /** + * Performs in-place conversion of all values in a map. + * + * @param map the map whose values are to be converted + */ + public static void convertFromDouble(Map<String, Object> map) { + if (map == null) { + return; + } + + Set<Entry<String, Object>> set = map.entrySet(); + + for (Entry<String, Object> entry : set) { + entry.setValue(convertFromDouble(entry.getValue())); + } + } + + /** + * Converts a value. If the value is a List, then it recursively converts the + * entries of the List. Likewise with a map, however, the map is converted in place. + * + * @param value value to be converted + * @return the converted value + */ + @SuppressWarnings({"unchecked"}) + public static Object convertFromDouble(Object value) { + if (value == null) { + return value; + } + + if (value instanceof List) { + convertFromDouble((List<Object>) value); + return value; + } + + if (value instanceof Map) { + convertFromDouble((Map<String, Object>) value); + return value; + } + + if (!(value instanceof Double)) { + return value; + } + + Double num = (Double) value; + long longval = num.longValue(); + + if (Double.compare(num.doubleValue(), longval) != 0) { + // it isn't integral - return unchanged value + return value; + } + + // it's integral - determine if it's an integer or a long + int intval = (int) longval; + + if (intval == longval) { + return intval; + } + + return longval; + } +} |