| /* |
| * 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 hivemall.utils.lang; |
| |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.InvocationTargetException; |
| |
| import javax.annotation.Nonnull; |
| import javax.annotation.Nullable; |
| |
| public final class Preconditions { |
| |
| private Preconditions() {} |
| |
| public static <T> T checkNotNull(T reference) { |
| if (reference == null) { |
| throw new NullPointerException(); |
| } |
| return reference; |
| } |
| |
| public static <T, E extends Throwable> T checkNotNull(@Nullable T reference, |
| @Nonnull Class<E> clazz) throws E { |
| if (reference == null) { |
| final E throwable; |
| try { |
| throwable = clazz.newInstance(); |
| } catch (InstantiationException | IllegalAccessException e) { |
| throw new IllegalStateException("Failed to instantiate a class: " + clazz.getName(), |
| e); |
| } |
| throw throwable; |
| } |
| return reference; |
| } |
| |
| public static <T, E extends Throwable> T checkNotNull(@Nullable T reference, |
| @Nonnull String errorMessage, @Nonnull Class<E> clazz) throws E { |
| if (reference == null) { |
| final E throwable; |
| try { |
| Constructor<E> constructor = clazz.getConstructor(String.class); |
| throwable = constructor.newInstance(errorMessage); |
| } catch (NoSuchMethodException | SecurityException e1) { |
| throw new IllegalStateException( |
| "Failed to get a Constructor(String): " + clazz.getName(), e1); |
| } catch (InstantiationException | IllegalAccessException | IllegalArgumentException |
| | InvocationTargetException e2) { |
| throw new IllegalStateException("Failed to instantiate a class: " + clazz.getName(), |
| e2); |
| } |
| throw throwable; |
| } |
| return reference; |
| } |
| |
| public static <T> T checkNotNull(T reference, @Nullable Object errorMessage) { |
| if (reference == null) { |
| throw new NullPointerException(String.valueOf(errorMessage)); |
| } |
| return reference; |
| } |
| |
| public static void checkArgument(boolean expression) { |
| if (!expression) { |
| throw new IllegalArgumentException(); |
| } |
| } |
| |
| public static <E extends Throwable> void checkArgument(boolean expression, |
| @Nonnull Class<E> clazz) throws E { |
| if (!expression) { |
| final E throwable; |
| try { |
| throwable = clazz.newInstance(); |
| } catch (InstantiationException | IllegalAccessException e) { |
| throw new IllegalStateException("Failed to instantiate a class: " + clazz.getName(), |
| e); |
| } |
| throw throwable; |
| } |
| } |
| |
| public static <E extends Throwable> void checkArgument(boolean expression, |
| @Nonnull Class<E> clazz, @Nullable Object errorMessage) throws E { |
| if (!expression) { |
| Constructor<E> constructor; |
| try { |
| constructor = clazz.getConstructor(String.class); |
| } catch (NoSuchMethodException | SecurityException e) { |
| throw new IllegalStateException("Failed to get a constructor of " + clazz.getName(), |
| e); |
| } |
| final E throwable; |
| try { |
| throwable = constructor.newInstance(errorMessage); |
| } catch (ReflectiveOperationException | IllegalArgumentException e) { |
| throw new IllegalStateException("Failed to instantiate a class: " + clazz.getName(), |
| e); |
| } |
| throw throwable; |
| } |
| } |
| |
| public static void checkArgument(boolean expression, @Nullable Object errorMessage) { |
| if (!expression) { |
| throw new IllegalArgumentException(String.valueOf(errorMessage)); |
| } |
| } |
| |
| public static void checkArgument(boolean expression, @Nullable String errorMessageTemplate, |
| @Nullable Object... errorMessageArgs) { |
| if (!expression) { |
| throw new IllegalArgumentException( |
| StringUtils.format(errorMessageTemplate, errorMessageArgs)); |
| } |
| } |
| |
| @Nonnull |
| public static int checkElementIndex(final int index, final int size) { |
| if (index < 0) { |
| throw new IndexOutOfBoundsException("index (" + index + ") must not be negative"); |
| } else if (size < 0) { |
| throw new IndexOutOfBoundsException("negative size: " + size); |
| } else if (index >= size) { |
| throw new IndexOutOfBoundsException( |
| "index (" + index + ") must be less than size (" + size + ")"); |
| } |
| return index; |
| } |
| |
| } |