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/**
* Copyright (c) 2016-present, RxJava Contributors.
*
* 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.
*/
package io.reactivex.internal.functions;
import io.reactivex.functions.BiPredicate;
/**
* Utility methods containing the backport of Java 7's Objects utility class.
* Named as such to avoid clash with java.util.Objects.
*/
public final class ObjectHelper {
/** Utility class. */
private ObjectHelper() {
throw new IllegalStateException("No instances!");
}
/**
* Verifies if the object is not null and returns it or throws a NullPointerException
* with the given message.
* @param the value type
* @param object the object to verify
* @param message the message to use with the NullPointerException
* @return the object itself
* @throws NullPointerException if object is null
*/
public static T requireNonNull(T object, String message) {
if (object == null) {
throw new NullPointerException(message);
}
return object;
}
/**
* Compares two potentially null objects with each other using Object.equals.
* @param o1 the first object
* @param o2 the second object
* @return the comparison result
*/
public static boolean equals(Object o1, Object o2) { // NOPMD
return o1 == o2 || (o1 != null && o1.equals(o2));
}
/**
* Returns the hashCode of a non-null object or zero for a null object.
* @param o the object to get the hashCode for.
* @return the hashCode
*/
public static int hashCode(Object o) {
return o != null ? o.hashCode() : 0;
}
/**
* Compares two integer values similar to Integer.compare.
* @param v1 the first value
* @param v2 the second value
* @return the comparison result
*/
public static int compare(int v1, int v2) {
return v1 < v2 ? -1 : (v1 > v2 ? 1 : 0);
}
/**
* Compares two long values similar to Long.compare.
* @param v1 the first value
* @param v2 the second value
* @return the comparison result
*/
public static int compare(long v1, long v2) {
return v1 < v2 ? -1 : (v1 > v2 ? 1 : 0);
}
static final BiPredicate EQUALS = new BiObjectPredicate();
/**
* Returns a BiPredicate that compares its parameters via Objects.equals().
* @param the value type
* @return the bi-predicate instance
*/
@SuppressWarnings("unchecked")
public static BiPredicate equalsPredicate() {
return (BiPredicate)EQUALS;
}
/**
* Validate that the given value is positive or report an IllegalArgumentException with
* the parameter name.
* @param value the value to validate
* @param paramName the parameter name of the value
* @return value
* @throws IllegalArgumentException if bufferSize <= 0
*/
public static int verifyPositive(int value, String paramName) {
if (value <= 0) {
throw new IllegalArgumentException(paramName + " > 0 required but it was " + value);
}
return value;
}
/**
* Validate that the given value is positive or report an IllegalArgumentException with
* the parameter name.
* @param value the value to validate
* @param paramName the parameter name of the value
* @return value
* @throws IllegalArgumentException if bufferSize <= 0
*/
public static long verifyPositive(long value, String paramName) {
if (value <= 0L) {
throw new IllegalArgumentException(paramName + " > 0 required but it was " + value);
}
return value;
}
static final class BiObjectPredicate implements BiPredicate {
@Override
public boolean test(Object o1, Object o2) {
return ObjectHelper.equals(o1, o2);
}
}
/**
* Trap null-check attempts on primitives.
* @param value the value to check
* @param message the message to print
* @return the value
* @deprecated this method should not be used as there is no need
* to check primitives for nullness.
*/
@Deprecated
public static long requireNonNull(long value, String message) {
throw new InternalError("Null check on a primitive: " + message);
}
}