/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later.
* See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
*/
package org.hibernate.cfg;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javax.persistence.AttributeConverter;
import javax.persistence.Converter;
import org.hibernate.AnnotationException;
import org.hibernate.AssertionFailure;
/**
* Externalized representation of an AttributeConverter
*
* @author Steve Ebersole
*
* @see org.hibernate.boot.spi.AttributeConverterDescriptor
*/
public class AttributeConverterDefinition {
private final AttributeConverter attributeConverter;
private final boolean autoApply;
private final Class entityAttributeType;
private final Class databaseColumnType;
/**
* Build an AttributeConverterDefinition from the AttributeConverter Class reference and
* whether or not to auto-apply it.
*
* @param attributeConverterClass The AttributeConverter Class
* @param autoApply Should the AttributeConverter be auto-applied?
*
* @return The constructed definition
*/
public static AttributeConverterDefinition from(Class<? extends AttributeConverter> attributeConverterClass, boolean autoApply) {
return new AttributeConverterDefinition(
instantiateAttributeConverter( attributeConverterClass ),
autoApply
);
}
private static AttributeConverter instantiateAttributeConverter(Class<? extends AttributeConverter> attributeConverterClass) {
try {
return attributeConverterClass.newInstance();
}
catch (Exception e) {
throw new AnnotationException(
"Unable to instantiate AttributeConverter [" + attributeConverterClass.getName() + "]",
e
);
}
}
/**
* Build an AttributeConverterDefinition from the AttributeConverter Class reference. The
* converter is searched for a {@link Converter} annotation to determine whether it should
* be treated as auto-apply. If the annotation is present, {@link Converter#autoApply()} is
* used to make that determination. If the annotation is not present, {@code false} is assumed.
*
* @param attributeConverterClass The converter class
*
* @return The constructed definition
*/
public static AttributeConverterDefinition from(Class<? extends AttributeConverter> attributeConverterClass) {
return from( instantiateAttributeConverter( attributeConverterClass ) );
}
/**
* Build an AttributeConverterDefinition from an AttributeConverter instance. The
* converter is searched for a {@link Converter} annotation to determine whether it should
* be treated as auto-apply. If the annotation is present, {@link Converter#autoApply()} is
* used to make that determination. If the annotation is not present, {@code false} is assumed.
*
* @param attributeConverter The AttributeConverter instance
*
* @return The constructed definition
*/
public static AttributeConverterDefinition from(AttributeConverter attributeConverter) {
boolean autoApply = false;
Converter converterAnnotation = attributeConverter.getClass().getAnnotation( Converter.class );
if ( converterAnnotation != null ) {
autoApply = converterAnnotation.autoApply();
}
return new AttributeConverterDefinition( attributeConverter, autoApply );
}
/**
* Build an AttributeConverterDefinition from the AttributeConverter instance and
* whether or not to auto-apply it.
*
* @param attributeConverter The AttributeConverter instance
* @param autoApply Should the AttributeConverter be auto-applied?
*
* @return The constructed definition
*/
public static AttributeConverterDefinition from(AttributeConverter attributeConverter, boolean autoApply) {
return new AttributeConverterDefinition( attributeConverter, autoApply );
}
public AttributeConverterDefinition(AttributeConverter attributeConverter, boolean autoApply) {
this.attributeConverter = attributeConverter;
this.autoApply = autoApply;
final Class attributeConverterClass = attributeConverter.getClass();
final ParameterizedType attributeConverterSignature = extractAttributeConverterParameterizedType( attributeConverterClass );
if ( attributeConverterSignature == null ) {
throw new AssertionFailure(
"Could not extract ParameterizedType representation of AttributeConverter definition " +
"from AttributeConverter implementation class [" + attributeConverterClass.getName() + "]"
);
}
if ( attributeConverterSignature.getActualTypeArguments().length < 2 ) {
throw new AnnotationException(
"AttributeConverter [" + attributeConverterClass.getName()
+ "] did not retain parameterized type information"
);
}
if ( attributeConverterSignature.getActualTypeArguments().length > 2 ) {
throw new AnnotationException(
"AttributeConverter [" + attributeConverterClass.getName()
+ "] specified more than 2 parameterized types"
);
}
entityAttributeType = extractClass( attributeConverterSignature.getActualTypeArguments()[0] );
if ( entityAttributeType == null ) {
throw new AnnotationException(
"Could not determine 'entity attribute' type from given AttributeConverter [" +
attributeConverterClass.getName() + "]"
);
}
databaseColumnType = extractClass(attributeConverterSignature.getActualTypeArguments()[1]);
if ( databaseColumnType == null ) {
throw new AnnotationException(
"Could not determine 'database column' type from given AttributeConverter [" +
attributeConverterClass.getName() + "]"
);
}
}
private ParameterizedType extractAttributeConverterParameterizedType(Type base) {
if ( base != null ) {
Class clazz = extractClass( base );
List<Type> types = new ArrayList<Type>();
types.add( clazz.getGenericSuperclass() );
types.addAll( Arrays.asList( clazz.getGenericInterfaces() ) );
for ( Type type : types ) {
type = resolveType( type, base );
if ( ParameterizedType.class.isInstance( type ) ) {
final ParameterizedType parameterizedType = (ParameterizedType) type;
if ( AttributeConverter.class.equals( parameterizedType.getRawType() ) ) {
return parameterizedType;
}
}
ParameterizedType parameterizedType = extractAttributeConverterParameterizedType( type );
if ( parameterizedType != null ) {
return parameterizedType;
}
}
}
return null;
}
private static Type resolveType(Type target, Type context) {
if ( target instanceof ParameterizedType ) {
return resolveParameterizedType( (ParameterizedType) target, context );
}
else if ( target instanceof TypeVariable ) {
return resolveTypeVariable( (TypeVariable) target, (ParameterizedType) context );
}
return target;
}
private static ParameterizedType resolveParameterizedType(final ParameterizedType parameterizedType, Type context) {
Type[] actualTypeArguments = parameterizedType.getActualTypeArguments();
final Type[] resolvedTypeArguments = new Type[actualTypeArguments.length];
for ( int idx = 0; idx < actualTypeArguments.length; idx++ ) {
resolvedTypeArguments[idx] = resolveType( actualTypeArguments[idx], context );
}
return new ParameterizedType() {
@Override
public Type[] getActualTypeArguments() {
return resolvedTypeArguments;
}
@Override
public Type getRawType() {
return parameterizedType.getRawType();
}
@Override
public Type getOwnerType() {
return parameterizedType.getOwnerType();
}
};
}
private static Type resolveTypeVariable(TypeVariable typeVariable, ParameterizedType context) {
Class clazz = extractClass( context.getRawType() );
TypeVariable[] typeParameters = clazz.getTypeParameters();
for ( int idx = 0; idx < typeParameters.length; idx++ ) {
if ( typeVariable.getName().equals( typeParameters[idx].getName() ) ) {
return resolveType( context.getActualTypeArguments()[idx], context );
}
}
return typeVariable;
}
public AttributeConverter getAttributeConverter() {
return attributeConverter;
}
public boolean isAutoApply() {
return autoApply;
}
public Class getEntityAttributeType() {
return entityAttributeType;
}
public Class getDatabaseColumnType() {
return databaseColumnType;
}
private static Class extractType(TypeVariable typeVariable) {
java.lang.reflect.Type[] boundTypes = typeVariable.getBounds();
if ( boundTypes == null || boundTypes.length != 1 ) {
return null;
}
return (Class) boundTypes[0];
}
private static Class extractClass(Type type) {
if ( type instanceof Class ) {
return (Class) type;
}
else if ( type instanceof ParameterizedType ) {
return extractClass( ( (ParameterizedType) type ).getRawType() );
}
return null;
}
@Override
public String toString() {
return String.format(
"%s[converterClass=%s, domainType=%s, jdbcType=%s]",
this.getClass().getName(),
attributeConverter.getClass().getName(),
entityAttributeType.getName(),
databaseColumnType.getName()
);
}
}