72 lines
1.8 KiB
Java
Executable File
72 lines
1.8 KiB
Java
Executable File
/* ====================================================================
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Licensed to the Apache Software Foundation (ASF) under one or more
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contributor license agreements. See the NOTICE file distributed with
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this work for additional information regarding copyright ownership.
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The ASF licenses this file to You under the Apache License, Version 2.0
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(the "License"); you may not use this file except in compliance with
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the License. You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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==================================================================== */
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package org.apache.poi.openxml4j.util;
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/**
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* An immutable object that could be defined as null.
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*
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* @author Julien Chable
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* @version 0.9
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*/
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public final class Nullable<E> {
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private E value;
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/**
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* Constructor.
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*/
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public Nullable() {
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// Do nothing
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}
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/**
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* Constructor.
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*
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* @param value
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* The value to set to this nullable.
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*/
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public Nullable(E value) {
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this.value = value;
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}
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/**
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* Get the store value if any.
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*
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* @return
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*/
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public E getValue() {
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return value;
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}
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/**
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* Get the status of this nullable.
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*
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* @return <b>true</b> if the nullable store a value (empty string is
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* considered to be a value) else <b>false</>.
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*/
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public boolean hasValue() {
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return value != null;
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}
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/**
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* Set the stored value to <i>null</i>.
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*/
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public void nullify() {
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value = null;
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}
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}
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