1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.support.provider; 18 19 import android.support.annotation.Nullable; 20 import android.text.TextUtils; 21 22 import java.util.Collection; 23 24 /** 25 * Simple static methods to be called at the start of your own methods to verify 26 * correct arguments and state. 27 * @hide 28 */ 29 final class Preconditions { checkArgument(boolean expression, String message)30 static void checkArgument(boolean expression, String message) { 31 if (!expression) { 32 throw new IllegalArgumentException(message); 33 } 34 } 35 checkArgumentNotNull(Object object, String message)36 static void checkArgumentNotNull(Object object, String message) { 37 if (object == null) { 38 throw new IllegalArgumentException(message); 39 } 40 } 41 checkArgumentEquals(String expected, @Nullable String actual, String message)42 static void checkArgumentEquals(String expected, @Nullable String actual, String message) { 43 if (!TextUtils.equals(expected, actual)) { 44 throw new IllegalArgumentException(String.format(message, String.valueOf(expected), 45 String.valueOf(actual))); 46 } 47 } 48 checkState(boolean expression, String message)49 static void checkState(boolean expression, String message) { 50 if (!expression) { 51 throw new IllegalStateException(message); 52 } 53 } 54 } 55