/*
* ====================================================================
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.http.util;
/**
* A set of utility methods to help produce consistent
* {@link Object#equals equals} and {@link Object#hashCode hashCode} methods.
*
*
* @since 4.0
*/
public final class
LangUtils {
public static final int
HASH_SEED = 17;
public static final int
HASH_OFFSET = 37;
/** Disabled default constructor. */
private
LangUtils() {
}
public static int
hashCode(final int
seed, final int
hashcode) {
return
seed *
HASH_OFFSET +
hashcode;
}
public static int
hashCode(final int
seed, final boolean
b) {
return
hashCode(
seed,
b ? 1 : 0);
}
public static int
hashCode(final int
seed, final
Object obj) {
return
hashCode(
seed,
obj != null ?
obj.
hashCode() : 0);
}
/**
* Check if two objects are equal.
*
* @param obj1 first object to compare, may be {@code null}
* @param obj2 second object to compare, may be {@code null}
* @return {@code true} if the objects are equal or both null
*/
public static boolean
equals(final
Object obj1, final
Object obj2) {
return
obj1 == null ?
obj2 == null :
obj1.
equals(
obj2);
}
/**
* Check if two object arrays are equal.
* <ul>
* <li>If both parameters are null, return {@code true}</li>
* <li>If one parameter is null, return {@code false}</li>
* <li>If the array lengths are different, return {@code false}</li>
* <li>Compare array elements using .equals(); return {@code false} if any comparisons fail.</li>
* <li>Return {@code true}</li>
* </ul>
*
* @param a1 first array to compare, may be {@code null}
* @param a2 second array to compare, may be {@code null}
* @return {@code true} if the arrays are equal or both null
*/
public static boolean
equals(final
Object[]
a1, final
Object[]
a2) {
if (
a1 == null) {
return
a2 == null;
} else {
if (
a2 != null &&
a1.length ==
a2.length) {
for (int
i = 0;
i <
a1.length;
i++) {
if (!
equals(
a1[
i],
a2[
i])) {
return false;
}
}
return true;
} else {
return false;
}
}
}
}