UUIDUserType

package edu.ufl.flmnh.db;

import java.io.Serializable;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Types;
import java.util.UUID;

import org.hibernate.HibernateException;
import org.hibernate.usertype.UserType;

public class UUIDUserType implements UserType {

	private static final String CAST_EXCEPTION_TEXT = "Cannot be cast to a java.util.UUID";

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.hibernate.usertype.UserType#assemble(java.io.Serializable,
	 * java.lang.Object)
	 */
	public Object assemble(Serializable cached, Object owner)
			throws HibernateException {
		if (!String.class.isAssignableFrom(cached.getClass())) {
			return null;
		}

		return UUID.fromString((String) cached);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.hibernate.usertype.UserType#deepCopy(java.lang.Object)
	 */
	public Object deepCopy(Object value) throws HibernateException {

		if (!UUID.class.isAssignableFrom(value.getClass())) {
			throw new HibernateException(value.getClass().toString()
					+ CAST_EXCEPTION_TEXT);
		}

		UUID other = (UUID) value;

		return UUID.fromString(other.toString());
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.hibernate.usertype.UserType#disassemble(java.lang.Object)
	 */
	public Serializable disassemble(Object value) throws HibernateException {
		return value.toString();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.hibernate.usertype.UserType#equals(java.lang.Object,
	 * java.lang.Object)
	 */
	public boolean equals(Object x, Object y) throws HibernateException {
		if (x == y)
			return true;

		if (!UUID.class.isAssignableFrom(x.getClass())) {
			throw new HibernateException(x.getClass().toString()
					+ CAST_EXCEPTION_TEXT);
		} else if (!UUID.class.isAssignableFrom(y.getClass())) {

			throw new HibernateException(y.getClass().toString()
					+ CAST_EXCEPTION_TEXT);
		}

		UUID a = (UUID) x;
		UUID b = (UUID) y;

		return a.equals(b);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.hibernate.usertype.UserType#hashCode(java.lang.Object)
	 */
	public int hashCode(Object x) throws HibernateException {
		if (!UUID.class.isAssignableFrom(x.getClass())) {
			throw new HibernateException(x.getClass().toString()
					+ CAST_EXCEPTION_TEXT);
		}

		return x.hashCode();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.hibernate.usertype.UserType#isMutable()
	 */
	public boolean isMutable() {
		return false;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.hibernate.usertype.UserType#nullSafeGet(java.sql.ResultSet,
	 * java.lang.String[], java.lang.Object)
	 */
	public Object nullSafeGet(ResultSet rs, String[] names, Object owner)
			throws HibernateException, SQLException {
		String value = rs.getString(names[0]);
		if (value == null) {
			return null;
		} else {
			return UUID.fromString(value);
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.hibernate.usertype.UserType#nullSafeSet(java.sql.PreparedStatement,
	 * java.lang.Object, int)
	 */
	public void nullSafeSet(PreparedStatement st, Object value, int index)
			throws HibernateException, SQLException {
		if (value == null) {
			st.setNull(index, Types.VARCHAR);
			return;
		}

		if (!UUID.class.isAssignableFrom(value.getClass())) {
			throw new HibernateException(value.getClass().toString()
					+ CAST_EXCEPTION_TEXT);
		}

		st.setString(index, value.toString());
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.hibernate.usertype.UserType#replace(java.lang.Object,
	 * java.lang.Object, java.lang.Object)
	 */
	public Object replace(Object original, Object target, Object owner)
			throws HibernateException {
		if (!UUID.class.isAssignableFrom(original.getClass())) {
			throw new HibernateException(original.getClass().toString()
					+ CAST_EXCEPTION_TEXT);
		}
		return UUID.fromString(original.toString());
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.hibernate.usertype.UserType#returnedClass()
	 */
	@SuppressWarnings("unchecked")
	public Class returnedClass() {
		return UUID.class;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.hibernate.usertype.UserType#sqlTypes()
	 */
	public int[] sqlTypes() {
		return new int[] { Types.CHAR };
	}
}