View Javadoc
1   /*
2    * *************************************************************************************************************************************************************
3    *
4    * SteelBlue: DCI User Interfaces
5    * http://tidalwave.it/projects/steelblue
6    *
7    * Copyright (C) 2015 - 2025 by Tidalwave s.a.s. (http://tidalwave.it)
8    *
9    * *************************************************************************************************************************************************************
10   *
11   * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
12   * You may obtain a copy of the License at
13   *
14   *     http://www.apache.org/licenses/LICENSE-2.0
15   *
16   * 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
17   * CONDITIONS OF ANY KIND, either express or implied.  See the License for the specific language governing permissions and limitations under the License.
18   *
19   * *************************************************************************************************************************************************************
20   *
21   * git clone https://bitbucket.org/tidalwave/steelblue-src
22   * git clone https://github.com/tidalwave-it/steelblue-src
23   *
24   * *************************************************************************************************************************************************************
25   */
26  package it.tidalwave.ui.function;
27  
28  import jakarta.annotation.Nonnull;
29  import it.tidalwave.ui.core.ChangingSource;
30  
31  /***************************************************************************************************************************************************************
32   *
33   * @since   2.0-ALPHA-1
34   * @author  Fabrizio Giudici
35   *
36   **************************************************************************************************************************************************************/
37  public class NonEmptyFunction extends UnaryBoundFunctionSupport<String, Boolean>
38    {
39      @Nonnull
40      public static NonEmptyFunction nonEmpty (@Nonnull final ChangingSource<String> source)
41        {
42          return new NonEmptyFunction(source);
43        }
44  
45      public NonEmptyFunction (@Nonnull final ChangingSource<String> source)
46        {
47          super(source);
48        }
49  
50      @Override
51      protected void onSourceChange (@Nonnull final String oldSourceValue, @Nonnull final String newSourceValue)
52        {
53          final boolean oldValue = function(oldSourceValue);
54          value = function(newSourceValue);
55          fireValueChanged(oldValue, (boolean)value);
56        }
57  
58      @Override @Nonnull
59      protected Boolean function (final String value)
60        {
61          return (value != null) && !value.trim().isEmpty();
62        }
63    }