be.fedict.eid.pkira.blm.hibernateutil.SchemaGenerator.java Source code

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Here is the source code for be.fedict.eid.pkira.blm.hibernateutil.SchemaGenerator.java

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/*
 * eID PKI RA Project.
 * Copyright (C) 2010-2014 FedICT.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License version
 * 3.0 as published by the Free Software Foundation.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, see
 * http://www.gnu.org/licenses/.
 */
package be.fedict.eid.pkira.blm.hibernateutil;

import java.io.File;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Queue;
import java.util.Set;

import javax.persistence.Entity;

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

/**
 * Hibernate Schema Generator Code based on
 * http://jandrewthompson.blogspot.com/2009
 * /10/how-to-generate-ddl-scripts-from.html
 */
public class SchemaGenerator {

    /**
     * Holds the classnames of hibernate dialects for easy reference.
     */
    private static enum Dialect {
        HSQL("org.hibernate.dialect.HSQLDialect"), MYSQL("org.hibernate.dialect.MySQLDialect"), ORACLE(
                "org.hibernate.dialect.Oracle10gDialect"), POSTGRES("org.hibernate.dialect.PostgreSQLDialect");

        private String dialectClass;

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

        public String getDialectClass() {
            return dialectClass;
        }
    }

    public static void main(String[] args) throws Exception {
        String workingDir;
        if (args.length > 0) {
            workingDir = new File(args[0]).getCanonicalPath();
        } else {
            workingDir = new File("target").getCanonicalPath();
        }

        SchemaGenerator gen = new SchemaGenerator("be.fedict.eid.pkira.blm.model", workingDir);
        gen.generate(Dialect.MYSQL);
        gen.generate(Dialect.ORACLE);
        gen.generate(Dialect.HSQL);
        gen.generate(Dialect.POSTGRES);
    }

    private final AnnotationConfiguration cfg;
    private final String workingDir;

    public SchemaGenerator(String packageName, String workingDir) throws Exception {
        this.workingDir = workingDir;

        // Find entities on the class path
        Set<String> classNames = enumerateClasses(workingDir + "/classes");
        Set<Class<?>> entityClasses = new HashSet<Class<?>>();
        for (String className : classNames) {
            Class<?> clazz = Class.forName(className);
            if (clazz.getAnnotation(Entity.class) != null) {
                entityClasses.add(clazz);
            }
        }

        if (entityClasses.size() == 0) {
            throw new Exception("No entity classes found in classes directory: " + workingDir + "/classes");
        }
        System.out.println("Found " + entityClasses.size() + " entity classes.");

        // Create hibernate configuration
        cfg = new AnnotationConfiguration();
        cfg.setProperty("hibernate.hbm2ddl.auto", "create");
        for (Class<?> entityClass : entityClasses) {
            cfg.addAnnotatedClass(entityClass);
        }
    }

    private Set<String> enumerateClasses(String path) {
        Set<String> result = new HashSet<String>();
        Queue<String> todo = new LinkedList<String>();
        todo.add("");

        while (!todo.isEmpty()) {
            String relativePath = todo.poll();
            String thePath = path + relativePath;

            for (File entry : new File(thePath).listFiles()) {
                if (entry.isDirectory()) {
                    todo.add(relativePath + '/' + entry.getName());
                } else if (entry.isFile() && entry.getName().endsWith(".class")) {
                    String file = relativePath + '/' + entry.getName();
                    file = file.substring(1, file.length() - 6);
                    file = file.replaceAll("/", ".");
                    result.add(file);
                }
            }
        }

        return result;
    }

    /**
     * Method that actually creates the file.
     * 
     * @param dbDialect
     *            to use
     */
    private void generate(Dialect dialect) {
        new java.io.File(workingDir + "/schema").mkdirs();

        cfg.setProperty("hibernate.dialect", dialect.getDialectClass());

        SchemaExport export = new SchemaExport(cfg);
        export.setDelimiter(";");
        export.setOutputFile(workingDir + "/schema/ddl_" + dialect.name().toLowerCase() + ".sql");
        export.execute(true, false, false, false);
    }
}