/*
* 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.
*/
package org.apache.shindig.common.util;
import org.hamcrest.Description;
import org.hamcrest.Matcher;
import static org.hamcrest.Matchers.equalTo;
import org.hamcrest.StringDescription;
import java.util.Collection;
import java.util.Map;
/**
* Provides methods for checking conditions and arguments, throwing an
* appropriate {@code RuntimeException} when the checks fail.
* The main goal of this class is to ensure that appropriate exception types
* with clear messages are thrown while minimizing code duplication.
*
* <p>Use this class instead of {@code assert} when you want to enforce that
* the check is always performed. These are designed for testing arguments
* and preconditions that make up a method's contract.
*
* <p>Example:
*
* <pre class="code">public void setContentData(String contentData) {
* Check.eq(contentType, ContentType.HTML,
* "getContentData() only valid for HTML gadgets");
* Check.notNull(contentData);
* this.contentData = contentData;
*}</pre>
*
* <p>A generic check that can use any {@link org.hamcrest.Matcher} is provided
* a la JUnit. Various matchers can be created using static methods from
* {@link org.hamcrest.Matchers}.
*
* <pre class="code">Check.that(string, containsString("foo"));
*Check.that(string, anyOf(startsWith("foo"), endsWith("bar")));</pre>
*/
public final class Check {
/**
* Private constructor for this class, do not allow instantiation
*/
private Check() {
}
/**
* Checks that {@code condition} is {@code true}.
*
* @throws IllegalStateException if the check fails.
*/
public static void is(boolean condition, String message) {
if (!condition) {
throw new IllegalStateException(message);
}
}
/**
* Checks that {@code condition} is {@code true}.
*
* @throws IllegalStateException if the check fails.
*/
public static void is(boolean condition, String message, Object... args) {
if (!condition) {
throw new IllegalStateException(String.format(message, args));
}
}
/**
* Checks that {@code first} equals {@code second} using
* {@link org.hamcrest.Matchers#equalTo}.
*
* @throws IllegalStateException if the check fails.
*/
public static void eq(Object first, Object second, String message) {
that(first, equalTo(second), message);
}
/**
* Checks that {@code first} equals {@code second} using
* {@link org.hamcrest.Matchers#equalTo}.
*
* @throws IllegalStateException if the check fails.
*/
public static void eq(Object first, Object second, String message,
Object... args) {
that(first, equalTo(second), String.format(message, args));
}
/**
* Checks that {@code actual} matches {@code matcher} from Hamcrest.
*
* @throws IllegalStateException if the check fails.
*/
public static <T> void that(T actual, Matcher<T> matcher) {
that(actual, matcher, "");
}
/**
* Checks that {@code actual} matches {@code matcher} from Hamcrest.
*
* @throws IllegalStateException if the check fails.
*/
public static <T> void that(T actual, Matcher<T> matcher, String message) {
if (!matcher.matches(actual)) {
Description description = new StringDescription();
if (message != null && message.length() > 0) {
description.appendText(message).appendText(" - ");
}
description.appendValue(actual).appendText(" must be ");
matcher.describeTo(description);
throw new IllegalStateException(matcher.toString());
}
}
/**
* Checks that {@code actual} matches {@code matcher} from Hamcrest.
*
* @throws IllegalStateException if the check fails.
*/
public static <T> void that(T actual, Matcher<T> matcher, String message,
Object... args) {
that(actual, matcher, String.format(message, args));
}
/**
* Checks that {@code ref} is not {@code null}.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notNull(Object ref) {
if (ref == null) {
throw new IllegalArgumentException("Object must be non-null");
}
}
/**
* Checks that {@code ref} is not {@code null}.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notNull(Object ref, String message) {
if (ref == null) {
throw new IllegalArgumentException(message);
}
}
/**
* Checks that {@code ref} is not {@code null}.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notNull(Object ref, String message, Object... args) {
if (ref == null) {
throw new IllegalArgumentException(String.format(message, args));
}
}
/**
* Checks that {@code ref} is a (or a subclass of) {@code clazz}.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void isA(Object ref, Class<?> clazz) {
if (ref != null && !(clazz.isAssignableFrom(ref.getClass()))) {
throw new IllegalArgumentException(
String.format("Object must be an instance of %s", clazz));
}
}
/**
* Checks that {@code ref} is a (or a subclass of) {@code clazz}.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void isA(Object ref, Class<?> clazz, String message) {
if (ref != null && !(clazz.isAssignableFrom(ref.getClass()))) {
throw new IllegalArgumentException(message);
}
}
/**
* Checks that {@code ref} is a (or a subclass of) {@code clazz}.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void isA(Object ref, Class<?> clazz, String message,
Object... args) {
if (ref != null && !(clazz.isAssignableFrom(ref.getClass()))) {
throw new IllegalArgumentException(String.format(message, args));
}
}
/**
* Checks that {@code string} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notEmpty(String string) {
if (string == null || string.length() == 0) {
throw new IllegalArgumentException("String must be non-empty");
}
}
/**
* Checks that {@code string} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notEmpty(String string, String message) {
if (string == null || string.length() == 0) {
throw new IllegalArgumentException(message);
}
}
/**
* Checks that {@code string} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notEmpty(String string, String message, Object... args) {
if (string == null || string.length() == 0) {
throw new IllegalArgumentException(String.format(message, args));
}
}
/**
* Checks that {@code array} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notEmpty(Object[] array) {
if (array == null || array.length == 0) {
throw new IllegalArgumentException("Array must be non-empty");
}
}
/**
* Checks that {@code array} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notEmpty(Object[] array, String message) {
if (array == null || array.length == 0) {
throw new IllegalArgumentException(message);
}
}
/**
* Checks that {@code array} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notEmpty(Object[] array, String message, Object... args) {
if (array == null || array.length == 0) {
throw new IllegalArgumentException(String.format(message, args));
}
}
/**
* Checks that {@code collection} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
* or empty.
*/
public static void notEmpty(Collection<?> collection) {
if (collection == null || collection.isEmpty()) {
throw new IllegalArgumentException("Collection must be non-empty");
}
}
/**
* Checks that {@code collection} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
* or empty.
*/
public static void notEmpty(Collection<?> collection, String message) {
if (collection == null || collection.isEmpty()) {
throw new IllegalArgumentException(message);
}
}
/**
* Checks that {@code collection} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
* or empty.
*/
public static void notEmpty(Collection<?> collection, String message,
Object... args) {
if (collection == null || collection.isEmpty()) {
throw new IllegalArgumentException(String.format(message, args));
}
}
/**
* Checks that {@code map} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notEmpty(Map<?, ?> map) {
if (map == null || map.isEmpty()) {
throw new IllegalArgumentException("Map must be non-empty");
}
}
/**
* Checks that {@code map} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notEmpty(Map<?, ?> map, String message) {
if (map == null || map.isEmpty()) {
throw new IllegalArgumentException(message);
}
}
/**
* Checks that {@code map} is not {@code null} and not empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void notEmpty(Map<?, ?> map, String message, Object... args) {
if (map == null || map.isEmpty()) {
throw new IllegalArgumentException(String.format(message, args));
}
}
/**
* Checks that {@code array} contains no {@code null} elements.
* It is not an error for the argument itself to be {@code null} or empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void noNulls(Object[] array) {
if (array != null && array.length > 0) {
for (Object element : array) {
if (element == null) {
throw new IllegalArgumentException(
"Array must contain only non-null elements");
}
}
}
}
/**
* Checks that {@code array} contains no {@code null} elements.
* It is not an error for the argument itself to be {@code null} or empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void noNulls(Object[] array, String message) {
if (array != null && array.length > 0) {
for (Object element : array) {
if (element == null) {
throw new IllegalArgumentException(message);
}
}
}
}
/**
* Checks that {@code array} contains no {@code null} elements.
* It is not an error for the argument itself to be {@code null} or empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static void noNulls(Object[] array, String message, Object... args) {
if (array != null && array.length > 0) {
for (Object element : array) {
if (element == null) {
throw new IllegalArgumentException(String.format(message, args));
}
}
}
}
/**
* Checks that {@code iterable} contains no {@code null} elements.
* It is not an error for {@code iterable} itself to be {@code null} or empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static <E> void noNulls(Iterable<E> iterable) {
if (iterable != null) {
for (E element : iterable) {
if (element == null) {
throw new IllegalArgumentException(
"Iterable must contain only non-null elements");
}
}
}
}
/**
* Checks that {@code iterable} contains no {@code null} elements.
* It is not an error for {@code iterable} itself to be {@code null} or empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static <E> void noNulls(Iterable<E> iterable, String message) {
if (iterable != null) {
for (E element : iterable) {
if (element == null) {
throw new IllegalArgumentException(message);
}
}
}
}
/**
* Checks that {@code iterable} contains no {@code null} elements.
* It is not an error for {@code iterable} itself to be {@code null} or empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static <E> void noNulls(Iterable<E> iterable, String message,
Object... args) {
if (iterable != null) {
for (E element : iterable) {
if (element == null) {
throw new IllegalArgumentException(String.format(message, args));
}
}
}
}
/**
* Checks that {@code map} contains no {@code null} keys or values.
* It is not an error for {@code map} itself to be {@code null} or empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static <K, V> void noNulls(Map<K, V> map) {
if (map != null) {
for (Map.Entry<K, V> entry : map.entrySet()) {
if (entry.getKey() == null || entry.getValue() == null) {
throw new IllegalArgumentException(
"Map must contain only non-null keys and values");
}
}
}
}
/**
* Checks that {@code map} contains no {@code null} elements.
* It is not an error for {@code map} itself to be {@code null} or empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static <K, V> void noNulls(Map<K, V> map, String message) {
if (map != null) {
for (Map.Entry<K, V> entry : map.entrySet()) {
if (entry.getKey() == null || entry.getValue() == null) {
throw new IllegalArgumentException(message);
}
}
}
}
/**
* Checks that {@code map} contains no {@code null} elements.
* It is not an error for {@code map} itself to be {@code null} or empty.
*
* @throws IllegalArgumentException if the check fails.
*/
public static <K, V> void noNulls(Map<K, V> map, String message,
Object... args) {
if (map != null) {
for (Map.Entry<K, V> entry : map.entrySet()) {
if (entry.getKey() == null || entry.getValue() == null) {
throw new IllegalArgumentException(String.format(message, args));
}
}
}
}
}