We ha开发者_JS百科ve been using the GenericEnumUserType for our extensible enumerations and our classes fail to load in JBoss 6, on a Hibernate 3.6+ container.
The following error is thrown
#abc state=Create: java.lang.NoSuchMethodError: org.hibernate.type.Type
Factory.basic(Ljava/lang/String;)Lorg/hibernate/type/Type;
on the following code
type = (NullableType)TypeFactory.basic(identifierType.getName());
Unfortunately @Enumerated does not work if you need to serialize based on something other than the Enum's ordinal or name. I've managed to find a solution (modified slightly from here).
import java.io.Serializable;
import java.lang.reflect.Method;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Properties;
import org.hibernate.HibernateException;
import org.hibernate.type.AbstractSingleColumnStandardBasicType;
import org.hibernate.type.TypeResolver;
import org.hibernate.usertype.ParameterizedType;
import org.hibernate.usertype.UserType;
public class GenericEnumUserType implements UserType, ParameterizedType {
private Class<? extends Enum> enumClass;
private Class<?> identifierType;
private Method identifierMethod;
private Method valueOfMethod;
private static final String defaultIdentifierMethodName = "name";
private static final String defaultValueOfMethodName = "valueOf";
private AbstractSingleColumnStandardBasicType type;
private int[] sqlTypes;
@Override
public void setParameterValues( Properties parameters )
{
String enumClassName = parameters.getProperty("enumClass");
try
{
enumClass = Class.forName( enumClassName ).asSubclass( Enum.class );
}
catch (ClassNotFoundException exception) {
throw new HibernateException("Enum class not found", exception);
}
String identifierMethodName = parameters.getProperty( "identifierMethod", defaultIdentifierMethodName );
try
{
identifierMethod = enumClass.getMethod( identifierMethodName,
new Class[0]);
identifierType = identifierMethod.getReturnType();
}
catch (Exception exception)
{
throw new HibernateException("Failed to optain identifier method",
exception);
}
TypeResolver tr = new TypeResolver();
type = (AbstractSingleColumnStandardBasicType)tr.basic( identifierType.getName() );
if (type == null)
{
throw new HibernateException( "Unsupported identifier type " + identifierType.getName() );
}
sqlTypes = new int[] { type.sqlType() };
String valueOfMethodName = parameters.getProperty( "valueOfMethod",
defaultValueOfMethodName);
try
{
valueOfMethod = enumClass.getMethod( valueOfMethodName,
new Class[] { identifierType } );
}
catch ( Exception exception )
{
throw new HibernateException( "Failed to optain valueOf method",
exception);
}
}
@Override
public Class returnedClass()
{
return enumClass;
}
@Override
public Object nullSafeGet( ResultSet rs, String[] names, Object owner )
throws HibernateException, SQLException
{
Object identifier = type.get( rs, names[0] );
try
{
return valueOfMethod.invoke( enumClass, new Object[] { identifier } );
}
catch ( Exception exception )
{
throw new HibernateException( "Exception while invoking valueOfMethod of enumeration class: ",
exception);
}
}
public void nullSafeSet( PreparedStatement st, Object value, int index )
throws HibernateException, SQLException
{
try
{
Object identifier = value != null ? identifierMethod.invoke( value,
new Object[0] ) : null;
st.setObject( index, identifier );
}
catch ( Exception exception )
{
throw new HibernateException( "Exception while invoking identifierMethod of enumeration class: ",
exception );
}
}
@Override
public int[] sqlTypes()
{
return sqlTypes;
}
@Override
public Object assemble( Serializable cached, Object owner )
throws HibernateException
{
return cached;
}
@Override
public Object deepCopy( Object value )
throws HibernateException
{
return value;
}
@Override
public Serializable disassemble( Object value )
throws HibernateException
{
return (Serializable) value;
}
@Override
public boolean equals( Object x, Object y )
throws HibernateException
{
return x == y;
}
@Override
public int hashCode( Object x )
throws HibernateException
{
return x.hashCode();
}
public boolean isMutable()
{
return false;
}
public Object replace( Object original, Object target, Object owner )
throws HibernateException
{
return original;
}
}
There's no TypeFactory.basic(String) in Hibernate 3.6 anymore. Compare the javadocs:
http://docs.jboss.org/hibernate/core/3.6/javadocs/org/hibernate/type/TypeFactory.html http://docs.jboss.org/hibernate/core/3.3/api/org/hibernate/type/TypeFactory.html
I think it's now time to move from a custom UserType to the standard @Enumerated :-)
I looked into the TypeResolver's code and took note of the inner implementation of the basic
method, which is using classes not already deprecated. So, I replaced
TypeResolver tr = new TypeResolver();
type = (AbstractSingleColumnStandardBasicType)tr.basic( identifierType.getName() );
with
type = (AbstractSingleColumnStandardBasicType<? extends Object>) new TypeConfiguration()
.getBasicTypeRegistry().getRegisteredType(identifierType.getName());
And... So far, so good.
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