craterdog.collections.Association Maven / Gradle / Ivy
/************************************************************************
* Copyright (c) Crater Dog Technologies(TM). All Rights Reserved. *
************************************************************************
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. *
* *
* This code is free software; you can redistribute it and/or modify it *
* under the terms of The MIT License (MIT), as published by the Open *
* Source Initiative. (See http://opensource.org/licenses/MIT) *
************************************************************************/
package craterdog.collections;
import craterdog.core.Composite;
import craterdog.utils.NaturalComparator;
import java.util.Comparator;
import java.util.Objects;
import org.slf4j.ext.XLogger;
import org.slf4j.ext.XLoggerFactory;
/**
* This class defines an association between a key and a value.
*
* @author Derk Norton
* @param The type of the key in the association.
* @param The type of the value in the association.
*/
public class Association implements Composite> {
static private final XLogger logger = XLoggerFactory.getXLogger(Association.class);
/**
* The key in the association.
*/
public final K key;
/**
* The value in the association.
*/
public V value;
/**
* This constructor creates a new key-value association.
* @param key The key in the association.
* @param value The value in the association.
*/
public Association(K key, V value) {
logger.entry(key, value);
this.key = key;
this.value = value;
logger.exit();
}
@Override
public boolean equals(Object object) {
logger.entry(object);
boolean result = false;
if (object != null && getClass() == object.getClass()) {
final Association that = (Association) object;
result = Objects.equals(this.key, that.key) && Objects.equals(this.value, that.value);
}
logger.exit(result);
return result;
}
@Override
public int hashCode() {
logger.entry();
int hash = 7;
hash = 13 * hash + Objects.hashCode(this.key);
hash = 13 * hash + Objects.hashCode(this.value);
logger.exit(hash);
return hash;
}
@Override
public int compareTo(Association that) {
logger.entry(that);
Comparator comparator = new NaturalComparator<>();
int result = comparator.compare(this.key, that.key);
logger.exit(result);
return result;
}
@Override
public String toString() {
logger.entry();
String string = toString("");
logger.exit(string);
return string;
}
@Override
public String toString(String indentation) {
logger.entry(indentation);
StringBuilder builder = new StringBuilder();
builder.append(key);
builder.append(": ");
if (value instanceof Composite) {
Composite composite = (Composite) value;
builder.append(composite.toString(indentation));
} else {
builder.append(value);
}
String string = builder.toString();
logger.exit(string);
return string;
}
@Override
public >> T copy() {
@SuppressWarnings("unchecked")
T copy = (T) new Association<>(key, value);
return copy;
}
}