io.netty.util.internal.ObjectUtil Maven / Gradle / Ivy
/*
* Copyright 2014 The Netty Project
*
* The Netty Project 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.
*/
package io.netty.util.internal;
/**
* A grab-bag of useful utility methods.
*/
public final class ObjectUtil {
private ObjectUtil() {
}
/**
* Checks that the given argument is not null. If it is, throws {@link NullPointerException}.
* Otherwise, returns the argument.
*/
public static T checkNotNull(T arg, String text) {
if (arg == null) {
throw new NullPointerException(text);
}
return arg;
}
/**
* Checks that the given argument is strictly positive. If it is, throws {@link IllegalArgumentException}.
* Otherwise, returns the argument.
*/
public static int checkPositive(int i, String name) {
if (i <= 0) {
throw new IllegalArgumentException(name + ": " + i + " (expected: > 0)");
}
return i;
}
/**
* Checks that the given argument is strictly positive. If it is, throws {@link IllegalArgumentException}.
* Otherwise, returns the argument.
*/
public static long checkPositive(long i, String name) {
if (i <= 0) {
throw new IllegalArgumentException(name + ": " + i + " (expected: > 0)");
}
return i;
}
/**
* Checks that the given argument is positive or zero. If it is, throws {@link IllegalArgumentException}.
* Otherwise, returns the argument.
*/
public static int checkPositiveOrZero(int i, String name) {
if (i < 0) {
throw new IllegalArgumentException(name + ": " + i + " (expected: >= 0)");
}
return i;
}
/**
* Checks that the given argument is positive or zero. If it is, throws {@link IllegalArgumentException}.
* Otherwise, returns the argument.
*/
public static long checkPositiveOrZero(long i, String name) {
if (i < 0) {
throw new IllegalArgumentException(name + ": " + i + " (expected: >= 0)");
}
return i;
}
/**
* Checks that the given argument is neither null nor empty.
* If it is, throws {@link NullPointerException} or {@link IllegalArgumentException}.
* Otherwise, returns the argument.
*/
public static T[] checkNonEmpty(T[] array, String name) {
checkNotNull(array, name);
checkPositive(array.length, name + ".length");
return array;
}
/**
* Resolves a possibly null Integer to a primitive int, using a default value.
* @param wrapper the wrapper
* @param defaultValue the default value
* @return the primitive value
*/
public static int intValue(Integer wrapper, int defaultValue) {
return wrapper != null ? wrapper : defaultValue;
}
/**
* Resolves a possibly null Long to a primitive long, using a default value.
* @param wrapper the wrapper
* @param defaultValue the default value
* @return the primitive value
*/
public static long longValue(Long wrapper, long defaultValue) {
return wrapper != null ? wrapper : defaultValue;
}
}