Assertions.java

/*
 * Created by LuaView.
 * Copyright (c) 2017, Alibaba Group. All rights reserved.
 *
 * This source code is licensed under the MIT.
 * For the full copyright and license information,please view the LICENSE file in the root directory of this source tree.
 */

package com.taobao.luaview.util;

import com.taobao.luaview.annotations.Nullable;

import java.util.List;
import java.util.Map;

/**
 * Assert
 *
 * @author song
 * @date 16/4/13
 * 主要功能描述
 * 修改描述
 * 下午3:45 song XXX
 */
public class Assertions {

    public Assertions() {
    }

    public static <T> T assumeNotNull(@Nullable T object) {
        return object;
    }

    public static <T> T assumeNotNull(@Nullable T object, String explanation) {
        return object;
    }

    public static <T> T assertNotNull(@Nullable T object) {
        if(object == null) {
            throw new AssertionError();
        } else {
            return object;
        }
    }

    public static <T> T assertNotNull(@Nullable T object, String explanation) {
        if(object == null) {
            throw new AssertionError(explanation);
        } else {
            return object;
        }
    }

    public static <T> T getAssumingNotNull(List<T> list, int index) {
        return list.get(index);
    }

    public static <T> T getAssertingNotNull(List<T> list, int index) {
        assertCondition(0 <= index && index < list.size());
        return assertNotNull(list.get(index));
    }

    public static <K, V> V getAssumingNotNull(Map<K, V> map, K key) {
        return map.get(key);
    }

    public static <K, V> V getAssertingNotNull(Map<K, V> map, K key) {
        assertCondition(map.containsKey(key));
        return assertNotNull(map.get(key));
    }

    public static void assumeCondition(boolean condition) {
    }

    public static void assumeCondition(boolean condition, String explanation) {
    }

    public static void assertCondition(boolean condition) {
        if(!condition) {
            throw new AssertionError();
        }
    }

    public static void assertCondition(boolean condition, String explanation) {
        if(!condition) {
            throw new AssertionError(explanation);
        }
    }

    public static AssertionError assertUnreachable() {
        throw new AssertionError();
    }

    public static AssertionError assertUnreachable(String explanation) {
        throw new AssertionError(explanation);
    }

    public static AssertionError assertUnreachable(Exception exception) {
        throw new AssertionError(exception);
    }
}