org.eclipse.emf.teneo.hibernate.mapping.XSDDuration.java Source code

Introduction

Here is the source code for org.eclipse.emf.teneo.hibernate.mapping.XSDDuration.java

Source

/**
 * <copyright>
 *
 * Copyright (c) 2005, 2006, 2007, 2008 Springsite BV (The Netherlands) and others
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   Martin Taal
 * </copyright>
 *
 * $Id: XSDDuration.java,v 1.5 2008/09/04 10:45:17 mtaal Exp $
 */
package org.eclipse.emf.teneo.hibernate.mapping;

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

import javax.xml.datatype.DatatypeFactory;
import javax.xml.datatype.Duration;

import org.eclipse.emf.teneo.hibernate.HbMapperException;
import org.hibernate.usertype.UserType;

/**
 * Provides a Hibernate extension (called a UserType) to support the xml Duration type. The duration
 * is persisted as a string.
 * 
 * @author <a href="mailto:mtaal@elver.org">Martin Taal</a>
 */
public class XSDDuration implements UserType {

    private static final int[] SQL_TYPES = { Types.VARCHAR };
    private final DatatypeFactory factory;

    /**
     * Construct a new VARCHAR custom data type.
     */
    public XSDDuration() {
        try {
            factory = DatatypeFactory.newInstance();
        } catch (Exception e) {
            throw new HbMapperException("Exception while creating datatypefactory ", e);
        }
    }

    /**
     * Return the types of the columns that this UserType will serialize into.
     * 
     * @return a single column of type VARCHAR.
     */
    public int[] sqlTypes() {
        return SQL_TYPES;
    }

    /**
     * Return the Java class of the object that is serialized for the column.
     * 
     * @return the Java instance class associated with the EMF DataType.
     */
    public Class<?> returnedClass() {
        return javax.xml.datatype.Duration.class;
    }

    /**
     * Is this datatype mutable?
     * 
     * @return Being conservative - false always.
     */
    public boolean isMutable() {
        return false;
    }

    /**
     * Provide a copy of the datatypes. Converts to String and then back to datatype again.
     * 
     * @param value
     *            the value to copy.
     * @return the value always.
     */
    public Object deepCopy(Object value) {
        if (value == null) {
            return null;
        }
        return factory.newDuration(((Duration) value).toString());
    }

    /**
     * Are the two objects equal?
     * 
     * @param x
     *            an object to compare.
     * @param y
     *            an object to compare.
     * @return a standard equals test between the objects.
     */
    public boolean equals(Object x, Object y) {
        if (x == y) {
            return true;
        }
        if (x == null || y == null) {
            return false;
        }
        return x.equals(y);
    }

    /**
     * Populate the model object property from the ResultSet.
     * 
     * @param resultSet
     *            the non-null ResultSet from which the field will be populated.
     * @param names
     *            the names of the columns.
     * @param owner
     *            the owning object.
     * @return null if the column's value is null; otherwise, use the EMF factory to construct a new
     *         instance of the custom EMF data type from the contents of the String value of the
     *         column.
     * @throws SQLException
     *             if the value cannot be retrieved from the ResultSet.
     */
    public Object nullSafeGet(ResultSet resultSet, String[] names, Object owner) throws SQLException {

        final String data = resultSet.getString(names[0]);
        if (data == null) {
            return null;
        }
        return factory.newDuration(data);
    }

    /**
     * Populate the database statement from the model object property.
     * 
     * @param statement
     *            the non-null Statement to insert the value into.
     * @param value
     *            the object to convert.
     * @param index
     *            the index into the statement where to insert the converted value.
     * @throws SQLException
     *             if the converted value cannot be set in the statement.
     */
    public void nullSafeSet(PreparedStatement statement, Object value, int index) throws SQLException {
        String pvalue = null;
        if (value != null) {
            pvalue = ((Duration) value).toString();
        }
        if (pvalue != null) {
            statement.setString(index, pvalue);
        } else {
            statement.setNull(index, Types.VARCHAR);
        }
    }

    /**
     * No-op implementation.
     * 
     * @param value
     *            the value to dissemble.
     * @return the value passed in.
     */
    public Serializable disassemble(Object value) {
        if (value == null) {
            return null;
        }
        return ((Duration) value).toString();
    }

    /**
     * No-op implementation.
     * 
     * @param cachedValue
     *            the value to assemble.
     * @param owner
     *            the owning object.
     * @return the cachedValue passed in.
     */
    public Object assemble(Serializable cachedValue, Object owner) {
        return cachedValue;
    }

    /**
     * No-op implementation.
     * 
     * @param original
     *            the value to replace.
     * @param target
     *            the target object.
     * @param owner
     *            the owning object.
     * @return the original value passed in.
     */
    public Object replace(Object original, Object target, Object owner) {
        return original;
    }

    /**
     * No-op implementation.
     * 
     * @param x
     *            the object to get the hashcode for.
     * @return x's hashcode.
     */
    public int hashCode(Object x) {
        return x.hashCode();
    }
}