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Diffstat (limited to 'src/org/unitConverter/math/ZeroIsNullMap.java')
-rw-r--r-- | src/org/unitConverter/math/ZeroIsNullMap.java | 129 |
1 files changed, 0 insertions, 129 deletions
diff --git a/src/org/unitConverter/math/ZeroIsNullMap.java b/src/org/unitConverter/math/ZeroIsNullMap.java deleted file mode 100644 index 10e4d52..0000000 --- a/src/org/unitConverter/math/ZeroIsNullMap.java +++ /dev/null @@ -1,129 +0,0 @@ -/** - * Copyright (C) 2019 Adrien Hopkins - * - * This program is free software: you can redistribute it and/or modify - * it under the terms of the GNU Affero General Public License as published by - * the Free Software Foundation, either version 3 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU Affero General Public License for more details. - * - * You should have received a copy of the GNU Affero General Public License - * along with this program. If not, see <https://www.gnu.org/licenses/>. - */ -package org.unitConverter.math; - -import java.util.AbstractMap; -import java.util.ArrayList; -import java.util.Collection; -import java.util.HashSet; -import java.util.List; -import java.util.Map; -import java.util.Objects; -import java.util.Set; - -/** - * A "wrapper" for an existing map that treats a zero value as equivalent to null. - * - * @author Adrien Hopkins - * @since 2019-10-16 - * @param <T> - * type of key - */ -public final class ZeroIsNullMap<T> extends AbstractMap<T, Integer> { - /** - * Create a ZeroIsNullMap. This method always creates a new map. - * - * @param <T> - * type of key - * @param map - * map to input - * @return map that treats zero as null - * @throws NullPointerException - * if map is null - * @since 2019-10-16 - */ - public static <T> Map<T, Integer> create(final Map<T, Integer> map) { - return new ZeroIsNullMap<>(Objects.requireNonNull(map, "map must not be null.")); - } - - private final Map<T, Integer> map; - - /** - * Creates the {@code ObjectProductMap}. - * - * @param map - * @since 2019-10-16 - */ - private ZeroIsNullMap(final Map<T, Integer> map) { - this.map = map; - } - - @Override - public void clear() { - this.map.clear(); - } - - @Override - public boolean containsKey(final Object key) { - return this.map.containsKey(key) && this.map.get(key) != 0; - } - - @Override - public boolean containsValue(final Object value) { - return this.values().contains(value); - } - - @Override - public Set<Entry<T, Integer>> entrySet() { - final Set<Entry<T, Integer>> entrySet = new HashSet<>(this.map.entrySet()); - entrySet.removeIf(e -> e.getValue() == 0); - return entrySet; - } - - @Override - public Integer get(final Object key) { - final Integer i = this.map.get(key); - if (Objects.equals(i, 0)) - return null; - else - return i; - } - - @Override - public Set<T> keySet() { - final Set<T> keySet = new HashSet<>(this.map.keySet()); - keySet.removeIf(k -> this.map.get(k) == 0); - return keySet; - } - - @Override - public Integer put(final T key, final Integer value) { - if (value != 0) - return this.map.put(key, value); - else - return null; - } - - @Override - public void putAll(final Map<? extends T, ? extends Integer> m) { - for (final T key : m.keySet()) { - this.put(key, m.get(key)); - } - } - - @Override - public Integer remove(final Object key) { - return this.map.remove(key); - } - - @Override - public Collection<Integer> values() { - final List<Integer> values = new ArrayList<>(this.map.values()); - values.removeIf(i -> i == 0); - return values; - } -}
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