/*
* Copyright 2012-2014 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.boot.bind;
import java.util.EnumSet;
import java.util.Set;
import org.springframework.core.convert.ConversionFailedException;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.convert.TypeDescriptor;
import org.springframework.core.convert.converter.Converter;
import org.springframework.core.convert.converter.ConverterFactory;
import org.springframework.core.convert.support.GenericConversionService;
import org.springframework.util.Assert;
/**
* Internal {@link ConversionService} used by {@link RelaxedDataBinder} to support
* additional relaxed conversion.
*
* @author Phillip Webb
* @since 1.1.0
*/
class RelaxedConversionService implements ConversionService {
private final ConversionService conversionService;
private final GenericConversionService additionalConverters;
/**
* Create a new {@link RelaxedConversionService} instance.
* @param conversionService and option root conversion service
*/
public RelaxedConversionService(ConversionService conversionService) {
this.conversionService = conversionService;
this.additionalConverters = new GenericConversionService();
this.additionalConverters
.addConverterFactory(new StringToEnumIgnoringCaseConverterFactory());
this.additionalConverters.addConverter(new StringToCharArrayConverter());
}
@Override
public boolean canConvert(Class<?> sourceType, Class<?> targetType) {
return (this.conversionService != null && this.conversionService.canConvert(
sourceType, targetType))
|| this.additionalConverters.canConvert(sourceType, targetType);
}
@Override
public boolean canConvert(TypeDescriptor sourceType, TypeDescriptor targetType) {
return (this.conversionService != null && this.conversionService.canConvert(
sourceType, targetType))
|| this.additionalConverters.canConvert(sourceType, targetType);
}
@Override
@SuppressWarnings("unchecked")
public <T> T convert(Object source, Class<T> targetType) {
Assert.notNull(targetType, "The targetType to convert to cannot be null");
return (T) convert(source, TypeDescriptor.forObject(source),
TypeDescriptor.valueOf(targetType));
}
@Override
public Object convert(Object source, TypeDescriptor sourceType,
TypeDescriptor targetType) {
if (this.conversionService != null) {
try {
return this.conversionService.convert(source, sourceType, targetType);
}
catch (ConversionFailedException ex) {
// Ignore and try the additional converters
}
}
return this.additionalConverters.convert(source, sourceType, targetType);
}
/**
* Clone of Spring's package private StringToEnumConverterFactory, but ignoring the
* case of the source.
*/
@SuppressWarnings({ "unchecked", "rawtypes" })
private static class StringToEnumIgnoringCaseConverterFactory implements
ConverterFactory<String, Enum> {
@Override
public <T extends Enum> Converter<String, T> getConverter(Class<T> targetType) {
Class<?> enumType = targetType;
while (enumType != null && !enumType.isEnum()) {
enumType = enumType.getSuperclass();
}
Assert.notNull(enumType, "The target type " + targetType.getName()
+ " does not refer to an enum");
return new StringToEnum(enumType);
}
private class StringToEnum<T extends Enum> implements Converter<String, T> {
private final Class<T> enumType;
public StringToEnum(Class<T> enumType) {
this.enumType = enumType;
}
@Override
public T convert(String source) {
if (source.length() == 0) {
// It's an empty enum identifier: reset the enum value to null.
return null;
}
source = source.trim();
for (T candidate : (Set<T>) EnumSet.allOf(this.enumType)) {
if (candidate.name().equalsIgnoreCase(source)) {
return candidate;
}
}
throw new IllegalArgumentException("No enum constant "
+ this.enumType.getCanonicalName() + "." + source);
}
}
}
}