StringEnumUserType.java

/*
 * Copyright 2011-2013 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package kr.debop4j.data.hibernate.usertype;

import lombok.extern.slf4j.Slf4j;
import org.hibernate.HibernateException;
import org.hibernate.annotations.common.util.ReflectHelper;
import org.hibernate.engine.spi.SessionImplementor;
import org.hibernate.type.StandardBasicTypes;
import org.hibernate.usertype.ParameterizedType;
import org.hibernate.usertype.UserType;

import java.io.Serializable;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Objects;
import java.util.Properties;

/**
 * Enum 값을 문자열로 DB에 저장하고, 로드 시에 Enum 값으로 파싱해서 설정한다.
 * Jpa@author 배성혁 ( sunghyouk.bae@gmail.com )
 *
 * @since 12. 11. 19.
 */
@Slf4j
public class StringEnumUserType implements UserType, ParameterizedType, Serializable {

    private Class<Enum> enumClass;

    @Override
    @SuppressWarnings("unchecked")
    public void setParameterValues(final Properties parameters) {
        String enumClassName = parameters.getProperty("enumClassName");
        try {
            enumClass = ReflectHelper.classForName(enumClassName);
        } catch (ClassNotFoundException e) {
            throw new HibernateException("Enum class not found. enumClassName=" + enumClassName, e);
        }
    }

    @Override
    public int[] sqlTypes() {
        return new int[] { StandardBasicTypes.STRING.sqlType() };
    }

    @Override
    public Class returnedClass() {
        return enumClass;
    }

    @Override
    public boolean equals(Object x, Object y) throws HibernateException {
        return Objects.equals(x, y);
    }

    @Override
    public int hashCode(Object x) throws HibernateException {
        return Objects.hashCode(x);
    }

    @Override
    public Object nullSafeGet(ResultSet rs, String[] names, SessionImplementor session, Object owner)
            throws HibernateException, SQLException {

        String value = rs.getString(names[0]);
        return rs.wasNull() ? null : Enum.valueOf(enumClass, value);
    }

    @Override
    public void nullSafeSet(PreparedStatement st, Object value, int index, SessionImplementor session)
            throws HibernateException, SQLException {

        if (value == null)
            st.setNull(index, sqlTypes()[0]);
        else
            st.setString(index, ((Enum) value).name());
    }

    @Override
    public Object deepCopy(Object value) throws HibernateException {
        return value;
    }

    @Override
    public boolean isMutable() {
        return false;
    }

    @Override
    public Serializable disassemble(Object value) throws HibernateException {
        return (Serializable) deepCopy(value);
    }

    @Override
    public Object assemble(Serializable cached, Object owner) throws HibernateException {
        return cached;
    }

    @Override
    public Object replace(Object original, Object target, Object owner) throws HibernateException {
        return original;
    }

    private static final long serialVersionUID = 4135696095152036946L;
}