/*
* Copyright (C) 2012 The Guava Authors
*
* Licensed 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 com.google.common.testing;
import static com.google.common.base.Preconditions.checkNotNull;
import com.google.common.base.CharMatcher;
import com.google.common.base.Charsets;
import com.google.common.base.Equivalence;
import com.google.common.base.Joiner;
import com.google.common.base.Splitter;
import com.google.common.base.Throwables;
import com.google.common.base.Ticker;
import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.BiMap;
import com.google.common.collect.HashBasedTable;
import com.google.common.collect.HashBiMap;
import com.google.common.collect.HashMultimap;
import com.google.common.collect.HashMultiset;
import com.google.common.collect.ImmutableBiMap;
import com.google.common.collect.ImmutableCollection;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableListMultimap;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableMultimap;
import com.google.common.collect.ImmutableMultiset;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.ImmutableSetMultimap;
import com.google.common.collect.ImmutableSortedMap;
import com.google.common.collect.ImmutableSortedMultiset;
import com.google.common.collect.ImmutableSortedSet;
import com.google.common.collect.ImmutableTable;
import com.google.common.collect.Iterables;
import com.google.common.collect.LinkedHashMultimap;
import com.google.common.collect.LinkedHashMultiset;
import com.google.common.collect.ListMultimap;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import com.google.common.collect.Multimap;
import com.google.common.collect.Multiset;
import com.google.common.collect.Ordering;
import com.google.common.collect.RowSortedTable;
import com.google.common.collect.SetMultimap;
import com.google.common.collect.Sets;
import com.google.common.collect.SortedMultiset;
import com.google.common.collect.Table;
import com.google.common.collect.TreeBasedTable;
import com.google.common.collect.TreeMultiset;
import com.google.common.primitives.Primitives;
import com.google.common.primitives.UnsignedInteger;
import com.google.common.primitives.UnsignedLong;
import com.google.common.reflect.AbstractInvocationHandler;
import com.google.common.reflect.Invokable;
import com.google.common.reflect.Parameter;
import com.google.common.reflect.Reflection;
import com.google.common.reflect.TypeToken;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.InputStream;
import java.io.Reader;
import java.io.StringReader;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.reflect.Array;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.TypeVariable;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.nio.Buffer;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.DoubleBuffer;
import java.nio.FloatBuffer;
import java.nio.IntBuffer;
import java.nio.LongBuffer;
import java.nio.ShortBuffer;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.Currency;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.NavigableMap;
import java.util.NavigableSet;
import java.util.Set;
import java.util.SortedMap;
import java.util.SortedSet;
import java.util.TreeMap;
import java.util.TreeSet;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.regex.Pattern;
import javax.annotation.Nullable;
/**
* Generates fresh instances of types that are different from each other (if possible).
*
* @author Ben Yu
*/
class FreshValueGenerator {
private static final ImmutableMap<Class<?>, Method> GENERATORS;
static {
ImmutableMap.Builder<Class<?>, Method> builder =
ImmutableMap.builder();
for (Method method : FreshValueGenerator.class.getDeclaredMethods()) {
if (method.isAnnotationPresent(Generates.class)) {
builder.put(method.getReturnType(), method);
}
}
GENERATORS = builder.build();
}
private final AtomicInteger differentiator = new AtomicInteger(1);
private final ListMultimap<Class<?>, Object> sampleInstances = ArrayListMultimap.create();
<T> void addSampleInstances(Class<T> type, Iterable<? extends T> instances) {
sampleInstances.putAll(checkNotNull(type), checkNotNull(instances));
}
/**
* Returns a fresh instance for {@code type} if possible. The returned instance could be:
* <ul>
* <li>exactly of the given type, including generic type parameters, such as
* {@code ImmutableList<String>};
* <li>of the raw type;
* <li>null if no fresh value can be generated.
* </ul>
*/
@Nullable final <T> T generate(TypeToken<T> type) {
// Not completely safe since sample instances are registered by raw types.
// But we assume the generic type parameters are mostly unimportant for these dummy values,
// because what really matters are equals/hashCode.
@SuppressWarnings("unchecked")
T result = (T) generateIfPossible(type);
return result;
}
@Nullable final <T> T generate(Class<T> type) {
return generate(TypeToken.of(type));
}
@Nullable private Object generateIfPossible(TypeToken<?> type) {
Class<?> rawType = type.getRawType();
List<Object> samples = sampleInstances.get(rawType);
Object sample = nextInstance(samples, null);
if (sample != null) {
return sample;
}
if (rawType.isEnum()) {
return nextInstance(rawType.getEnumConstants(), null);
}
if (type.isArray()) {
TypeToken<?> componentType = type.getComponentType();
Object array = Array.newInstance(componentType.getRawType(), 1);
Array.set(array, 0, generateIfPossible(componentType));
return array;
}
Method generator = GENERATORS.get(Primitives.unwrap(rawType));
if (generator != null) {
ImmutableList<Parameter> params = Invokable.from(generator).getParameters();
List<Object> args = Lists.newArrayListWithCapacity(params.size());
TypeVariable<?>[] typeVars = rawType.getTypeParameters();
for (int i = 0; i < params.size(); i++) {
TypeToken<?> paramType = type.resolveType(typeVars[i]);
// We require all @Generates methods to either be parameter-less or accept non-null
// fresh values for their generic parameter types.
Object argValue = generateIfPossible(paramType);
if (argValue == null) {
return defaultGenerate(rawType);
}
args.add(argValue);
}
try {
return generator.invoke(this, args.toArray());
} catch (InvocationTargetException e) {
Throwables.propagate(e.getCause());
} catch (Exception e) {
throw Throwables.propagate(e);
}
}
return defaultGenerate(rawType);
}
private Object defaultGenerate(Class<?> rawType) {
if (rawType.isInterface()) {
// always create a new proxy
return newProxy(rawType);
}
return ArbitraryInstances.get(rawType);
}
final <T> T newProxy(final Class<T> interfaceType) {
final int identity = freshInt();
return Reflection.newProxy(interfaceType, new AbstractInvocationHandler() {
@Override protected Object handleInvocation(Object proxy, Method method, Object[] args) {
return interfaceMethodCalled(interfaceType, method);
}
@Override public String toString() {
return paramString(interfaceType, identity);
}
});
}
/** Subclasses can override to provide different return value for proxied interface methods. */
Object interfaceMethodCalled(
@SuppressWarnings("unused") Class<?> interfaceType,
@SuppressWarnings("unused") Method method) {
throw new UnsupportedOperationException();
}
private <T> T nextInstance(T[] instances, T defaultValue) {
return nextInstance(Arrays.asList(instances), defaultValue);
}
private <T> T nextInstance(Collection<T> instances, T defaultValue) {
if (instances.isEmpty()) {
return defaultValue;
}
// freshInt() is 1-based.
return Iterables.get(instances, (freshInt() - 1) % instances.size());
}
private static String paramString(Class<?> type, int i) {
return type.getSimpleName() + '@' + i;
}
/**
* Annotates a method to be the instance generator of a certain type. The return type is the
* generated type. The method parameters are non-null fresh values for each method type variable
* in the same type variable declaration order of the return type.
*/
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
private @interface Generates {}
@Generates private Class<?> freshClass() {
return nextInstance(
ImmutableList.of(
int.class, long.class, void.class,
Object.class, Object[].class, Iterable.class),
Object.class);
}
@Generates private Object freshObject() {
return freshString();
}
@Generates private Number freshNumber() {
return freshInt();
}
@Generates private int freshInt() {
return differentiator.getAndIncrement();
}
@Generates private long freshLong() {
return freshInt();
}
@Generates private float freshFloat() {
return freshInt();
}
@Generates private double freshDouble() {
return freshInt();
}
@Generates private short freshShort() {
return (short) freshInt();
}
@Generates private byte freshByte() {
return (byte) freshInt();
}
@Generates private char freshChar() {
return freshString().charAt(0);
}
@Generates private boolean freshBoolean() {
return freshInt() % 2 == 0;
}
@Generates private UnsignedInteger freshUnsignedInteger() {
return UnsignedInteger.fromIntBits(freshInt());
}
@Generates private UnsignedLong freshUnsignedLong() {
return UnsignedLong.fromLongBits(freshLong());
}
@Generates private BigInteger freshBigInteger() {
return BigInteger.valueOf(freshInt());
}
@Generates private BigDecimal freshBigDecimal() {
return BigDecimal.valueOf(freshInt());
}
@Generates private CharSequence freshCharSequence() {
return freshString();
}
@Generates private String freshString() {
return Integer.toString(freshInt());
}
@Generates private Comparable<?> freshComparable() {
return freshString();
}
@Generates private Pattern freshPattern() {
return Pattern.compile(freshString());
}
@Generates private Charset freshCharset() {
return nextInstance(Charset.availableCharsets().values(), Charsets.UTF_8);
}
@Generates private Locale freshLocale() {
return nextInstance(Locale.getAvailableLocales(), Locale.US);
}
@Generates private Currency freshCurrency() {
for (Set<Locale> uselessLocales = Sets.newHashSet(); ; ) {
Locale locale = freshLocale();
if (uselessLocales.contains(locale)) { // exhausted all locales
return Currency.getInstance(Locale.US);
}
try {
return Currency.getInstance(locale);
} catch (IllegalArgumentException e) {
uselessLocales.add(locale);
}
}
}
// common.base
@Generates private Joiner freshJoiner() {
return Joiner.on(freshString());
}
@Generates private Splitter freshSplitter() {
return Splitter.on(freshString());
}
@Generates private <T> Equivalence<T> freshEquivalence() {
return new Equivalence<T>() {
@Override protected boolean doEquivalent(T a, T b) {
return false;
}
@Override protected int doHash(T t) {
return 0;
}
final String string = paramString(Equivalence.class, freshInt());
@Override public String toString() {
return string;
}
};
}
@Generates private CharMatcher freshCharMatcher() {
return new CharMatcher() {
@Override public boolean matches(char c) {
return false;
}
final String string = paramString(CharMatcher.class, freshInt());
@Override public String toString() {
return string;
}
};
}
@Generates private Ticker freshTicker() {
return new Ticker() {
@Override public long read() {
return 0;
}
final String string = paramString(Ticker.class, freshInt());
@Override public String toString() {
return string;
}
};
}
// collect
@Generates private <T> Comparator<T> freshComparator() {
return freshOrdering();
}
@Generates private <T> Ordering<T> freshOrdering() {
return new Ordering<T>() {
@Override public int compare(T left, T right) {
return 0;
}
final String string = paramString(Ordering.class, freshInt());
@Override public String toString() {
return string;
}
};
}
@Generates static private <E> Iterable<E> freshIterable(E freshElement) {
return freshList(freshElement);
}
@Generates static private <E> Collection<E> freshCollection(E freshElement) {
return freshList(freshElement);
}
@Generates static private <E> List<E> freshList(E freshElement) {
return freshArrayList(freshElement);
}
@Generates static private <E> ArrayList<E> freshArrayList(E freshElement) {
ArrayList<E> list = Lists.newArrayList();
list.add(freshElement);
return list;
}
@Generates static private <E> LinkedList<E> freshLinkedList(E freshElement) {
LinkedList<E> list = Lists.newLinkedList();
list.add(freshElement);
return list;
}
@Generates static private <E> ImmutableList<E> freshImmutableList(E freshElement) {
return ImmutableList.of(freshElement);
}
@Generates static private <E> ImmutableCollection<E> freshImmutableCollection(E freshElement) {
return freshImmutableList(freshElement);
}
@Generates static private <E> Set<E> freshSet(E freshElement) {
return freshHashSet(freshElement);
}
@Generates static private <E> HashSet<E> freshHashSet(E freshElement) {
return freshLinkedHashSet(freshElement);
}
@Generates static private <E> LinkedHashSet<E> freshLinkedHashSet(E freshElement) {
LinkedHashSet<E> set = Sets.newLinkedHashSet();
set.add(freshElement);
return set;
}
@Generates static private <E> ImmutableSet<E> freshImmutableSet(E freshElement) {
return ImmutableSet.of(freshElement);
}
@Generates static private <E extends Comparable<? super E>> SortedSet<E>
freshSortedSet(E freshElement) {
return freshNavigableSet(freshElement);
}
@Generates static private <E extends Comparable<? super E>> NavigableSet<E>
freshNavigableSet(E freshElement) {
return freshTreeSet(freshElement);
}
@Generates static private <E extends Comparable<? super E>> TreeSet<E> freshTreeSet(
E freshElement) {
TreeSet<E> set = Sets.newTreeSet();
set.add(freshElement);
return set;
}
@Generates static private <E extends Comparable<? super E>> ImmutableSortedSet<E>
freshImmutableSortedSet(E freshElement) {
return ImmutableSortedSet.of(freshElement);
}
@Generates static private <E> Multiset<E> freshMultiset(E freshElement) {
return freshHashMultiset(freshElement);
}
@Generates static private <E> HashMultiset<E> freshHashMultiset(E freshElement) {
HashMultiset<E> multiset = HashMultiset.create();
multiset.add(freshElement);
return multiset;
}
@Generates static private <E> LinkedHashMultiset<E> freshLinkedHashMultiset(E freshElement) {
LinkedHashMultiset<E> multiset = LinkedHashMultiset.create();
multiset.add(freshElement);
return multiset;
}
@Generates static private <E> ImmutableMultiset<E> freshImmutableMultiset(E freshElement) {
return ImmutableMultiset.of(freshElement);
}
@Generates static private <E extends Comparable<E>> SortedMultiset<E> freshSortedMultiset(
E freshElement) {
return freshTreeMultiset(freshElement);
}
@Generates static private <E extends Comparable<E>> TreeMultiset<E> freshTreeMultiset(
E freshElement) {
TreeMultiset<E> multiset = TreeMultiset.create();
multiset.add(freshElement);
return multiset;
}
@Generates static private <E extends Comparable<E>> ImmutableSortedMultiset<E>
freshImmutableSortedMultiset(E freshElement) {
return ImmutableSortedMultiset.of(freshElement);
}
@Generates static private <K, V> Map<K, V> freshMap(K key, V value) {
return freshHashdMap(key, value);
}
@Generates static private <K, V> HashMap<K, V> freshHashdMap(K key, V value) {
return freshLinkedHashMap(key, value);
}
@Generates static private <K, V> LinkedHashMap<K, V> freshLinkedHashMap(K key, V value) {
LinkedHashMap<K, V> map = Maps.newLinkedHashMap();
map.put(key, value);
return map;
}
@Generates static private <K, V> ImmutableMap<K, V> freshImmutableMap(K key, V value) {
return ImmutableMap.of(key, value);
}
@Generates static private <K, V> ConcurrentMap<K, V> freshConcurrentMap(K key, V value) {
ConcurrentMap<K, V> map = Maps.newConcurrentMap();
map.put(key, value);
return map;
}
@Generates static private <K extends Comparable<? super K>, V> SortedMap<K, V>
freshSortedMap(K key, V value) {
return freshNavigableMap(key, value);
}
@Generates static private <K extends Comparable<? super K>, V> NavigableMap<K, V>
freshNavigableMap(K key, V value) {
return freshTreeMap(key, value);
}
@Generates static private <K extends Comparable<? super K>, V> TreeMap<K, V> freshTreeMap(
K key, V value) {
TreeMap<K, V> map = Maps.newTreeMap();
map.put(key, value);
return map;
}
@Generates static private <K extends Comparable<? super K>, V> ImmutableSortedMap<K, V>
freshImmutableSortedMap(K key, V value) {
return ImmutableSortedMap.of(key, value);
}
@Generates static private <K, V> Multimap<K, V> freshMultimap(K key, V value) {
return freshListMultimap(key, value);
}
@Generates static private <K, V> ImmutableMultimap<K, V> freshImmutableMultimap(K key, V value) {
return ImmutableMultimap.of(key, value);
}
@Generates static private <K, V> ListMultimap<K, V> freshListMultimap(K key, V value) {
return freshArrayListMultimap(key, value);
}
@Generates static private <K, V> ArrayListMultimap<K, V> freshArrayListMultimap(K key, V value) {
ArrayListMultimap<K, V> multimap = ArrayListMultimap.create();
multimap.put(key, value);
return multimap;
}
@Generates static private <K, V> ImmutableListMultimap<K, V> freshImmutableListMultimap(
K key, V value) {
return ImmutableListMultimap.of(key, value);
}
@Generates static private <K, V> SetMultimap<K, V> freshSetMultimap(K key, V value) {
return freshLinkedHashMultimap(key, value);
}
@Generates static private <K, V> HashMultimap<K, V> freshHashMultimap(K key, V value) {
HashMultimap<K, V> multimap = HashMultimap.create();
multimap.put(key, value);
return multimap;
}
@Generates static private <K, V> LinkedHashMultimap<K, V> freshLinkedHashMultimap(
K key, V value) {
LinkedHashMultimap<K, V> multimap = LinkedHashMultimap.create();
multimap.put(key, value);
return multimap;
}
@Generates static private <K, V> ImmutableSetMultimap<K, V> freshImmutableSetMultimap(
K key, V value) {
return ImmutableSetMultimap.of(key, value);
}
@Generates static private <K, V> BiMap<K, V> freshBimap(K key, V value) {
return freshHashBiMap(key, value);
}
@Generates static private <K, V> HashBiMap<K, V> freshHashBiMap(K key, V value) {
HashBiMap<K, V> bimap = HashBiMap.create();
bimap.put(key, value);
return bimap;
}
@Generates static private <K, V> ImmutableBiMap<K, V> freshImmutableBimap(
K key, V value) {
return ImmutableBiMap.of(key, value);
}
@Generates static private <R, C, V> Table<R, C, V> freshTable(R row, C column, V value) {
return freshHashBasedTable(row, column, value);
}
@Generates static private <R, C, V> HashBasedTable<R, C, V> freshHashBasedTable(
R row, C column, V value) {
HashBasedTable<R, C, V> table = HashBasedTable.create();
table.put(row, column, value);
return table;
}
@SuppressWarnings("rawtypes") // TreeBasedTable.create() is defined as such
@Generates static private <R extends Comparable, C extends Comparable, V> RowSortedTable<R, C, V>
freshRowSortedTable(R row, C column, V value) {
return freshTreeBasedTable(row, column, value);
}
@SuppressWarnings("rawtypes") // TreeBasedTable.create() is defined as such
@Generates static private <R extends Comparable, C extends Comparable, V> TreeBasedTable<R, C, V>
freshTreeBasedTable(R row, C column, V value) {
TreeBasedTable<R, C, V> table = TreeBasedTable.create();
table.put(row, column, value);
return table;
}
@Generates static private <R, C, V> ImmutableTable<R, C, V> freshImmutableTable(
R row, C column, V value) {
return ImmutableTable.of(row, column, value);
}
// common.reflect
@Generates private TypeToken<?> freshTypeToken() {
return TypeToken.of(freshClass());
}
// io types
@Generates private File freshFile() {
return new File(freshString());
}
@Generates private static ByteArrayInputStream freshByteArrayInputStream() {
return new ByteArrayInputStream(new byte[0]);
}
@Generates private static InputStream freshInputStream() {
return freshByteArrayInputStream();
}
@Generates private StringReader freshStringReader() {
return new StringReader(freshString());
}
@Generates private Reader freshReader() {
return freshStringReader();
}
@Generates private Readable freshReadable() {
return freshReader();
}
@Generates private Buffer freshBuffer() {
return freshCharBuffer();
}
@Generates private CharBuffer freshCharBuffer() {
return CharBuffer.allocate(freshInt());
}
@Generates private ByteBuffer freshByteBuffer() {
return ByteBuffer.allocate(freshInt());
}
@Generates private ShortBuffer freshShortBuffer() {
return ShortBuffer.allocate(freshInt());
}
@Generates private IntBuffer freshIntBuffer() {
return IntBuffer.allocate(freshInt());
}
@Generates private LongBuffer freshLongBuffer() {
return LongBuffer.allocate(freshInt());
}
@Generates private FloatBuffer freshFloatBuffer() {
return FloatBuffer.allocate(freshInt());
}
@Generates private DoubleBuffer freshDoubleBuffer() {
return DoubleBuffer.allocate(freshInt());
}
}