org.springframework.data.convert.PropertyValueConversionService Maven / Gradle / Ivy
/*
* Copyright 2022-2023 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
*
* https://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.convert;
import org.springframework.data.mapping.PersistentProperty;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
/**
* Conversion service based on {@link CustomConversions} used to convert domain and store values using
* {@link PropertyValueConverter property-specific converters}.
*
* @author Mark Paluch
* @see PropertyValueConverter
* @since 2.7
*/
public class PropertyValueConversionService {
private final PropertyValueConversions conversions;
/**
* Constructs a new instance of the {@link PropertyValueConversionService} initialized with the given,
* required {@link CustomConversions} for resolving the {@link PropertyValueConversions} used to
* convert {@link PersistentProperty} values during data access operations.
*
* @param conversions {@link CustomConversions} used to handle domain and store type conversions;
* must not be {@literal null}.
* @throws IllegalArgumentException if {@link CustomConversions} is {@literal null}.
* @see CustomConversions
*/
public PropertyValueConversionService(CustomConversions conversions) {
Assert.notNull(conversions, "CustomConversions must not be null");
PropertyValueConversions valueConversions = conversions.getPropertyValueConversions();
this.conversions = valueConversions != null ? valueConversions : NoOpPropertyValueConversions.INSTANCE;
}
/**
* Return {@literal true} if a {@link PropertyValueConverter} is registered for the {@link PersistentProperty}.
*
* If this method returns {@literal true}, it means {@link #read(Object, PersistentProperty, ValueConversionContext)}
* and {@link #write(Object, PersistentProperty, ValueConversionContext)} are capable of handling conversions.
*
* @param property {@link PersistentProperty property} to evaluate for registration.
* @return {@literal true} if a {@link PropertyValueConverter} is registered for the {@link PersistentProperty}.
* @see PersistentProperty
*/
public boolean hasConverter(PersistentProperty property) {
return conversions.hasValueConverter(property);
}
/**
* Convert a value from its store-native representation into its domain-specific type.
*
* @param value the value to convert. Can be {@code null}.
* @param property the underlying property.
* @param context the context object.
* @param
property type.
* @param value conversion context type.
* @return the value to be used in the domain model. Can be {@code null}.
*/
@Nullable
public , VCC extends ValueConversionContext
> Object read(@Nullable Object value,
P property, VCC context) {
PropertyValueConverter> converter = conversions
.getValueConverter(property);
return value != null ? converter.read(value, context)
: converter.readNull(context);
}
/**
* Convert a value from its domain-specific value into its store-native representation.
*
* @param value the value to convert. Can be {@code null}.
* @param property the underlying property.
* @param context the context object.
* @param property type.
* @param value conversion context type.
* @return the value to be written to the data store. Can be {@code null}.
*/
@Nullable
public , VCC extends ValueConversionContext
> Object write(@Nullable Object value,
P property, VCC context) {
PropertyValueConverter> converter = conversions
.getValueConverter(property);
return value != null ? converter.write(value, context)
: converter.writeNull(context);
}
enum NoOpPropertyValueConversions implements PropertyValueConversions {
INSTANCE;
@Override
public boolean hasValueConverter(PersistentProperty property) {
return false;
}
@Override
public , VCC extends ValueConversionContext> PropertyValueConverter getValueConverter(
P property) {
throw new UnsupportedOperationException("No PropertyValueConversions was configured");
}
}
}