/*
 * 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.type.descriptor.java;

import java.io.Serializable;
import java.util.Comparator;

import org.hibernate.internal.util.compare.ComparableComparator;
import org.hibernate.internal.util.compare.EqualsHelper;
import org.hibernate.type.descriptor.WrapperOptions;

Descriptor for the Java side of a value mapping.
Author:Steve Ebersole
/** * Descriptor for the Java side of a value mapping. * * @author Steve Ebersole */
public interface JavaTypeDescriptor<T> extends Serializable {
Retrieve the Java type handled here.
Returns:The Java type.
Deprecated:Use getJavaType() instead
/** * Retrieve the Java type handled here. * * @return The Java type. * * @deprecated Use {@link #getJavaType()} instead */
@Deprecated Class<T> getJavaTypeClass();
Get the Java type described
/** * Get the Java type described */
default Class<T> getJavaType() { // default on this side since #getJavaTypeClass is the currently implemented method return getJavaTypeClass(); }
Retrieve the mutability plan for this Java type.
/** * Retrieve the mutability plan for this Java type. */
@SuppressWarnings("unchecked") default MutabilityPlan<T> getMutabilityPlan() { return ImmutableMutabilityPlan.INSTANCE; }
Retrieve the natural comparator for this type.
/** * Retrieve the natural comparator for this type. */
default Comparator<T> getComparator() { return Comparable.class.isAssignableFrom( Comparable.class ) ? ComparableComparator.INSTANCE : null; }
Extract a proper hash code for this value.
Params:
  • value – The value for which to extract a hash code.
Returns:The extracted hash code.
/** * Extract a proper hash code for this value. * * @param value The value for which to extract a hash code. * * @return The extracted hash code. */
default int extractHashCode(T value) { if ( value == null ) { throw new IllegalArgumentException( "Value to extract hashCode from cannot be null" ); } return value.hashCode(); }
Determine if two instances are equal
Params:
  • one – One instance
  • another – The other instance
Returns:True if the two are considered equal; false otherwise.
/** * Determine if two instances are equal * * @param one One instance * @param another The other instance * * @return True if the two are considered equal; false otherwise. */
default boolean areEqual(T one, T another) { return EqualsHelper.areEqual( one, another ); }
Extract a loggable representation of the value.
Params:
  • value – The value for which to extract a loggable representation.
Returns:The loggable representation
/** * Extract a loggable representation of the value. * * @param value The value for which to extract a loggable representation. * * @return The loggable representation */
default String extractLoggableRepresentation(T value) { return toString( value ); } default String toString(T value) { return value == null ? "null" : value.toString(); } T fromString(String string);
Unwrap an instance of our handled Java type into the requested type.

As an example, if this is a JavaTypeDescriptor<Integer> and we are asked to unwrap the Integer value as a Long we would return something like Long.valueOf( value.longValue() ).

Intended use is during PreparedStatement binding.
Params:
  • value – The value to unwrap
  • type – The type as which to unwrap
  • options – The options
Type parameters:
  • <X> – The conversion type.
Returns:The unwrapped value.
/** * Unwrap an instance of our handled Java type into the requested type. * <p/> * As an example, if this is a {@code JavaTypeDescriptor<Integer>} and we are asked to unwrap * the {@code Integer value} as a {@code Long} we would return something like * <code>Long.valueOf( value.longValue() )</code>. * <p/> * Intended use is during {@link java.sql.PreparedStatement} binding. * * @param value The value to unwrap * @param type The type as which to unwrap * @param options The options * @param <X> The conversion type. * * @return The unwrapped value. */
<X> X unwrap(T value, Class<X> type, WrapperOptions options);
Wrap a value as our handled Java type.

Intended use is during ResultSet extraction.
Params:
  • value – The value to wrap.
  • options – The options
Type parameters:
  • <X> – The conversion type.
Returns:The wrapped value.
/** * Wrap a value as our handled Java type. * <p/> * Intended use is during {@link java.sql.ResultSet} extraction. * * @param value The value to wrap. * @param options The options * @param <X> The conversion type. * * @return The wrapped value. */
<X> T wrap(X value, WrapperOptions options); }