//$Id: IdentifierGeneratorFactory.java 9686 2006-03-27 16:47:06Z [email protected] $
package org.hibernate.id;
import java.io.Serializable;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Properties;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.HibernateException;
import org.hibernate.MappingException;
import org.hibernate.dialect.Dialect;
import org.hibernate.type.Type;
import org.hibernate.util.ReflectHelper;
/**
* Factory and helper methods for <tt>IdentifierGenerator</tt> framework.
*
* @author Gavin King
*/
public final class IdentifierGeneratorFactory {
private static final Log log = LogFactory.getLog(IdentifierGeneratorFactory.class);
/**
* Get the generated identifier when using identity columns
*/
public static Serializable getGeneratedIdentity(ResultSet rs, Type type)
throws SQLException, HibernateException, IdentifierGenerationException {
if ( !rs.next() ) {
throw new HibernateException( "The database returned no natively generated identity value" );
}
final Serializable id = IdentifierGeneratorFactory.get( rs, type );
if ( log.isDebugEnabled() ) log.debug( "Natively generated identity: " + id );
return id;
}
// unhappy about this being public ... is there a better way?
public static Serializable get(ResultSet rs, Type type)
throws SQLException, IdentifierGenerationException {
Class clazz = type.getReturnedClass();
if ( clazz==Long.class ) {
return new Long( rs.getLong(1) );
}
else if ( clazz==Integer.class ) {
return new Integer( rs.getInt(1) );
}
else if ( clazz==Short.class ) {
return new Short( rs.getShort(1) );
}
else if ( clazz==String.class ) {
return rs.getString(1);
}
else {
throw new IdentifierGenerationException("this id generator generates long, integer, short or string");
}
}
private static final HashMap GENERATORS = new HashMap();
public static final Serializable SHORT_CIRCUIT_INDICATOR = new Serializable() {
public String toString() { return "SHORT_CIRCUIT_INDICATOR"; }
};
public static final Serializable POST_INSERT_INDICATOR = new Serializable() {
public String toString() { return "POST_INSERT_INDICATOR"; }
};
static {
GENERATORS.put("uuid", UUIDHexGenerator.class);
GENERATORS.put("hilo", TableHiLoGenerator.class);
GENERATORS.put("assigned", Assigned.class);
GENERATORS.put("identity", IdentityGenerator.class);
GENERATORS.put("select", SelectGenerator.class);
GENERATORS.put("sequence", SequenceGenerator.class);
GENERATORS.put("seqhilo", SequenceHiLoGenerator.class);
GENERATORS.put("increment", IncrementGenerator.class);
GENERATORS.put("foreign", ForeignGenerator.class);
GENERATORS.put("guid", GUIDGenerator.class);
GENERATORS.put("uuid.hex", UUIDHexGenerator.class); //uuid.hex is deprecated
GENERATORS.put("sequence-identity", SequenceIdentityGenerator.class);
}
public static IdentifierGenerator create(String strategy, Type type, Properties params, Dialect dialect)
throws MappingException {
try {
Class clazz = getIdentifierGeneratorClass( strategy, dialect );
IdentifierGenerator idgen = (IdentifierGenerator) clazz.newInstance();
if (idgen instanceof Configurable) ( (Configurable) idgen).configure(type, params, dialect);
return idgen;
}
catch (Exception e) {
throw new MappingException("could not instantiate id generator", e);
}
}
public static Class getIdentifierGeneratorClass(String strategy, Dialect dialect) {
Class clazz = (Class) GENERATORS.get(strategy);
if ( "native".equals(strategy) ) clazz = dialect.getNativeIdentifierGeneratorClass();
try {
if (clazz==null) clazz = ReflectHelper.classForName(strategy);
}
catch (ClassNotFoundException e) {
throw new MappingException("could not interpret id generator strategy: " + strategy);
}
return clazz;
}
public static Number createNumber(long value, Class clazz) throws IdentifierGenerationException {
if ( clazz==Long.class ) {
return new Long(value);
}
else if ( clazz==Integer.class ) {
return new Integer( (int) value );
}
else if ( clazz==Short.class ) {
return new Short( (short) value );
}
else {
throw new IdentifierGenerationException("this id generator generates long, integer, short");
}
}
private IdentifierGeneratorFactory() {} //cannot be instantiated
}
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