org.ambraproject.hibernate.SchemaGenerator.java Source code

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Here is the source code for org.ambraproject.hibernate.SchemaGenerator.java

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/*
 * $HeadURL$
 * $Id$
 *
 * Copyright (c) 2006-2011 by Public Library of Science
 *     http://plos.org
 *     http://ambraproject.org
 *
 * 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 org.ambraproject.hibernate;

import org.hibernate.cfg.Configuration;
import org.hibernate.tool.hbm2ddl.SchemaExport;

import java.io.File;

/**
 * Tool for generating ddl from hibernate config.  Inspiration taken from <a href="http://jandrewthompson.blogspot.com/2009/10/how-to-generate-ddl-scripts-from.html">this
 * blog</a>
 *
 * @author Alex Kudlick Date: 6/2/11
 *         <p/>
 *         org.ambraproject.service
 */
public class SchemaGenerator {
    private Configuration configuration;
    private boolean updateSchema;
    private String outputDir;

    /**
     * Create a new schema generator
     *
     * @param updateSchema - true if the tables in the schema already exist and need to be dropped, false to create the
     *                     schema from scratch
     */
    public SchemaGenerator(boolean updateSchema, String outputDir) {
        this.configuration = new Configuration().configure();
        configuration.setProperty("format_sql", "true");
        this.updateSchema = updateSchema;
        this.outputDir = outputDir;
    }

    /**
     * Create a new schema generator that won't drop tables
     */
    public SchemaGenerator() {
        this(false, new File("").getAbsolutePath());
    }

    /**
     * Generate the sql for creating the schema
     *
     * @param dialect - Database dialect to use
     */
    public void generateSQL(Dialect dialect) {
        configuration.setProperty("hibernate.dialect", dialect.getDialectClass());

        SchemaExport export = new SchemaExport(configuration);
        export.setDelimiter(";");
        String outputFile = this.outputDir + File.separator + "ddl_" + dialect.name().toLowerCase() + ".sql";
        export.setOutputFile(outputFile);
        export.execute(false, false, false, !updateSchema);
    }

    /**
     * Run the schema creation script
     *
     * @param jdbcUrl  - the jdbc url for the database in which to run the script
     * @param dialect- the sql dialect for the database
     * @param username - the username for the database
     * @param password - the password to use
     */
    public void createSchema(String jdbcUrl, Dialect dialect, String username, String password) {
        configuration.setProperty("connection.url", jdbcUrl);
        configuration.setProperty("connection.username", username);
        configuration.setProperty("connection.password", password);
        configuration.setProperty("dialect", dialect.getDialectClass());
        configuration.setProperty("connection.driver_class", dialect.getDriverClass());
        SchemaExport export = new SchemaExport(configuration);
        export.setDelimiter(";");
        export.execute(false, true, false, !updateSchema);
    }

    /**
     * Holds the classnames of hibernate dialects for easy reference.
     */
    public static enum Dialect {
        ORACLE("org.hibernate.dialect.Oracle10gDialect", "oracle.jdbc.driver.OracleDriver"), MYSQL(
                "org.hibernate.dialect.MySQLDialect",
                "com.mysql.jdbc.Driver"), HSQL("org.hibernate.dialect.HSQLDialect", "org.hsqldb.jdbcDriver");

        private String dialectClass;
        private String driverClass;

        private Dialect(String dialectClass, String driverClass) {
            this.dialectClass = dialectClass;
            this.driverClass = driverClass;
        }

        public String getDialectClass() {
            return dialectClass;
        }

        public String getDriverClass() {
            return driverClass;
        }

        public static Dialect fromString(String arg) {
            if ("oracle".equals(arg.toLowerCase())) {
                return ORACLE;
            } else if ("mysql".equals(arg.toLowerCase())) {
                return MYSQL;
            } else if ("hsql".equals(arg.toLowerCase())) {
                return HSQL;
            }
            throw new IllegalArgumentException("Didn't recognize dialect: " + arg
                    + ";\n Must be one of: oracle mysql hsql (case insensitive)");
        }
    }
}