001/*
002 * Copyright 2015 SirWellington Tech.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package tech.sirwellington.alchemy.test.junit.runners;
018
019import java.lang.annotation.Retention;
020import java.lang.annotation.Target;
021import tech.sirwellington.alchemy.annotations.access.Internal;
022import tech.sirwellington.alchemy.annotations.access.NonInstantiable;
023import tech.sirwellington.alchemy.generator.AlchemyGenerator;
024
025import static java.lang.annotation.ElementType.FIELD;
026import static java.lang.annotation.RetentionPolicy.RUNTIME;
027import static tech.sirwellington.alchemy.generator.NumberGenerators.longs;
028import static tech.sirwellington.alchemy.generator.NumberGenerators.positiveLongs;
029import static tech.sirwellington.alchemy.test.Checks.Internal.checkNotNull;
030import static tech.sirwellington.alchemy.test.Checks.Internal.checkThat;
031import static tech.sirwellington.alchemy.test.junit.runners.GenerateLong.Type.POSITIVE;
032import static tech.sirwellington.alchemy.test.junit.runners.GenerateLong.Type.RANGE;
033
034/**
035 * Used in with the {@link AlchemyTestRunner}, this Annotations allows the 
036 * Runtime Injection of Generated Longs from the {@link AlchemyGenerator} library.
037 * 
038 * Example:
039 * <pre>
040 * {@code
041 * `@RunWith(AlchemyTestRunner.class)
042 * public class ExampleTest
043 * {
044 *   `@GenerateLongs(POSITIVE)
045 *    private long hits;
046 * 
047 *    ...
048 * }
049 * }
050 * </pre>
051 * Note, ticks (`) used to escape Javadocs.
052 * 
053 * @see GenerateInteger
054 * @see GenerateString
055 * 
056 * @author SirWellington
057 */
058@Target(FIELD)
059@Retention(RUNTIME)
060public @interface GenerateLong
061{
062
063    Type value() default POSITIVE;
064
065    long min() default 0;
066
067    long max() default 0;
068
069    public enum Type
070    {
071        POSITIVE,
072        NEGATIVE,
073        ANY,
074        RANGE;
075    }
076
077    @Internal
078    @NonInstantiable
079    class Values
080    {
081
082        private Values() throws IllegalAccessException
083        {
084            throw new IllegalAccessException("cannot instantiate");
085        }
086
087        static AlchemyGenerator<Long> createGeneratorFor(GenerateLong annotation)
088        {
089            checkNotNull(annotation, "missing annotation");
090
091            Type type = annotation.value();
092            checkNotNull(type, "@GenerateLong missing value");
093
094            if (type == RANGE)
095            {
096                long min = annotation.min();
097                long max = annotation.max();
098                checkThat(min < max, "@GenerateLong: min must be less than max");
099                return longs(min, max);
100            }
101
102            //Cover remaining cases
103            switch (type)
104            {
105                case POSITIVE:
106                    return positiveLongs();
107                case NEGATIVE:
108                    return longs(Long.MIN_VALUE, 0);
109                default:
110                    return longs(Long.MIN_VALUE, Long.MAX_VALUE);
111            }
112        }
113
114    }
115
116}