/*
* Copyright 2016-2017 the original author or 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 org.springframework.data.repository.util;
import io.vavr.collection.LinkedHashMap;
import io.vavr.collection.LinkedHashSet;
import io.vavr.collection.Traversable;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.springframework.core.convert.TypeDescriptor;
import org.springframework.core.convert.converter.ConditionalGenericConverter;
import org.springframework.core.convert.converter.Converter;
import org.springframework.data.repository.util.QueryExecutionConverters.WrapperType;
/**
* Converter implementations to map from and to Vavr collections.
*
* @author Oliver Gierke
* @author Christoph Strobl
* @since 2.0
*/
class VavrCollections {
public enum ToJavaConverter implements Converter<Object, Object> {
INSTANCE;
public WrapperType getWrapperType() {
return WrapperType.multiValue(io.vavr.collection.Traversable.class);
}
/*
* (non-Javadoc)
* @see org.springframework.core.convert.converter.Converter#convert(java.lang.Object)
*/
@Override
public Object convert(Object source) {
if (source instanceof io.vavr.collection.Seq) {
return ((io.vavr.collection.Seq<?>) source).toJavaList();
}
if (source instanceof io.vavr.collection.Map) {
return ((io.vavr.collection.Map<?, ?>) source).toJavaMap();
}
if (source instanceof io.vavr.collection.Set) {
return ((io.vavr.collection.Set<?>) source).toJavaSet();
}
throw new IllegalArgumentException("Unsupported Javaslang collection " + source.getClass());
}
}
public enum FromJavaConverter implements ConditionalGenericConverter {
INSTANCE {
/*
* (non-Javadoc)
* @see org.springframework.core.convert.converter.GenericConverter#getConvertibleTypes()
*/
@Override
public java.util.Set<ConvertiblePair> getConvertibleTypes() {
return CONVERTIBLE_PAIRS;
}
/*
* (non-Javadoc)
* @see org.springframework.core.convert.converter.ConditionalConverter#matches(org.springframework.core.convert.TypeDescriptor, org.springframework.core.convert.TypeDescriptor)
*/
@Override
public boolean matches(TypeDescriptor sourceType, TypeDescriptor targetType) {
// Prevent collections to be mapped to maps
if (sourceType.isCollection() && io.vavr.collection.Map.class.isAssignableFrom(targetType.getType())) {
return false;
}
// Prevent maps to be mapped to collections
if (sourceType.isMap() && !(io.vavr.collection.Map.class.isAssignableFrom(targetType.getType())
|| targetType.getType().equals(Traversable.class))) {
return false;
}
return true;
}
/*
* (non-Javadoc)
* @see org.springframework.core.convert.converter.GenericConverter#convert(java.lang.Object, org.springframework.core.convert.TypeDescriptor, org.springframework.core.convert.TypeDescriptor)
*/
@Override
public Object convert(Object source, TypeDescriptor sourceType, TypeDescriptor targetType) {
if (source instanceof List) {
return io.vavr.collection.List.ofAll((Iterable<?>) source);
}
if (source instanceof java.util.Set) {
return LinkedHashSet.ofAll((Iterable<?>) source);
}
if (source instanceof java.util.Map) {
return LinkedHashMap.ofAll((java.util.Map<?, ?>) source);
}
return source;
}
};
private static final Set<ConvertiblePair> CONVERTIBLE_PAIRS;
static {
Set<ConvertiblePair> pairs = new HashSet<>();
pairs.add(new ConvertiblePair(Collection.class, io.vavr.collection.Traversable.class));
pairs.add(new ConvertiblePair(Map.class, io.vavr.collection.Traversable.class));
CONVERTIBLE_PAIRS = Collections.unmodifiableSet(pairs);
}
}
}