com.sun.javafx.application.preferences.ChangedValue Maven / Gradle / Ivy
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package com.sun.javafx.application.preferences;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.Objects;
/**
* Contains information about a changed value.
*
* @param oldValue the old mappings
* @param newValue the new mappings
*/
public record ChangedValue(Object oldValue, Object newValue) {
/**
* Returns a map that contains the new or changed mappings of {@code current} compared to {@code old}.
* A value has changed if {@link Objects#equals(Object, Object)} or {@link Arrays#equals(Object[], Object[])}
* returns {@code false} when invoked with the old and new value.
*
* @param old the old mappings
* @param current the current mappings
* @return a mapping of keys to changed values
*/
public static Map getEffectiveChanges(Map old, Map current) {
Map changed = null;
for (Map.Entry entry : current.entrySet()) {
Object newValue = entry.getValue();
Object oldValue = old.get(entry.getKey());
if (!Objects.deepEquals(oldValue, newValue)) {
if (changed == null) {
changed = new HashMap<>();
}
changed.put(entry.getKey(), new ChangedValue(oldValue, newValue));
}
}
return changed != null ? changed : Map.of();
}
}