org.springframework.core.convert.support.StringToCollectionConverter Maven / Gradle / Ivy
/*
* Copyright 2002-2014 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.core.convert.support;
import java.util.Collection;
import java.util.Collections;
import java.util.Set;
import org.springframework.core.CollectionFactory;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.convert.TypeDescriptor;
import org.springframework.core.convert.converter.ConditionalGenericConverter;
import org.springframework.lang.Nullable;
import org.springframework.util.StringUtils;
/**
* Converts a comma-delimited String to a Collection.
* If the target collection element type is declared, only matches if
* {@code String.class} can be converted to it.
*
* @author Keith Donald
* @author Juergen Hoeller
* @since 3.0
*/
final class StringToCollectionConverter implements ConditionalGenericConverter {
private final ConversionService conversionService;
public StringToCollectionConverter(ConversionService conversionService) {
this.conversionService = conversionService;
}
@Override
public Set getConvertibleTypes() {
return Collections.singleton(new ConvertiblePair(String.class, Collection.class));
}
@Override
public boolean matches(TypeDescriptor sourceType, TypeDescriptor targetType) {
return (targetType.getElementTypeDescriptor() == null ||
this.conversionService.canConvert(sourceType, targetType.getElementTypeDescriptor()));
}
@Override
@Nullable
public Object convert(@Nullable Object source, TypeDescriptor sourceType, TypeDescriptor targetType) {
if (source == null) {
return null;
}
String string = (String) source;
String[] fields = StringUtils.commaDelimitedListToStringArray(string);
TypeDescriptor elementDesc = targetType.getElementTypeDescriptor();
Collection