WeakCopyFunctionSupport.java
- /*
- * *************************************************************************************************************************************************************
- *
- * SteelBlue: DCI User Interfaces
- * http://tidalwave.it/projects/steelblue
- *
- * Copyright (C) 2015 - 2025 by Tidalwave s.a.s. (http://tidalwave.it)
- *
- * *************************************************************************************************************************************************************
- *
- * 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.
- *
- * *************************************************************************************************************************************************************
- *
- * git clone https://bitbucket.org/tidalwave/steelblue-src
- * git clone https://github.com/tidalwave-it/steelblue-src
- *
- * *************************************************************************************************************************************************************
- */
- package it.tidalwave.ui.core.function;
- import jakarta.annotation.Nonnull;
- import it.tidalwave.ui.core.role.Changeable;
- import it.tidalwave.ui.core.ChangingSource;
- import lombok.extern.slf4j.Slf4j;
- /***************************************************************************************************************************************************************
- *
- * Changes the destination only at a certain condition in function of the target.
- *
- * @since 2.0-ALPHA-1
- * @author Fabrizio Giudici
- *
- **************************************************************************************************************************************************************/
- @Slf4j
- public abstract class WeakCopyFunctionSupport<T> extends UnaryBoundFunctionSupport<T, T> implements Changeable<T>
- {
- @Nonnull
- protected T targetValue;
- protected WeakCopyFunctionSupport (@Nonnull final ChangingSource<T> source)
- {
- super(source);
- }
- @Override
- protected void onSourceChange (@Nonnull final T oldSourceValue, @Nonnull final T newSourceValue)
- {
- final var oldValue = function(oldSourceValue);
- final var newValue = function(newSourceValue);
- if (shouldChange(oldValue, newValue))
- {
- value = newValue;
- fireValueChanged(oldValue, newValue);
- }
- }
- @Override
- public void set (final T value)
- {
- this.targetValue = value;
- }
- protected abstract boolean shouldChange (T oldValue, T newValue);
- @Override @Nonnull
- protected T function (@Nonnull final T value)
- {
- return value;
- }
- }