de.juplo.plugins.hibernate4.Hbm2DdlMojo.java Source code

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Here is the source code for de.juplo.plugins.hibernate4.Hbm2DdlMojo.java

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package de.juplo.plugins.hibernate4;

/*
 * Copyright 2001-2005 The Apache Software Foundation.
 *
 * 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.
 */

import com.pyx4j.log4j.MavenLogAppender;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.math.BigInteger;
import java.net.URL;
import java.net.URLClassLoader;
import java.security.MessageDigest;
import java.sql.Connection;
import java.sql.Driver;
import java.sql.DriverManager;
import java.sql.DriverPropertyInfo;
import java.sql.SQLException;
import java.sql.SQLFeatureNotSupportedException;
import java.util.Comparator;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Properties;
import java.util.Set;
import java.util.TreeSet;
import java.util.logging.Logger;

import javax.persistence.Embeddable;
import javax.persistence.Entity;
import javax.persistence.MappedSuperclass;

import org.apache.maven.plugin.AbstractMojo;
import org.apache.maven.plugin.MojoExecutionException;
import org.apache.maven.plugin.MojoFailureException;
import org.apache.maven.project.MavenProject;
import org.hibernate.cfg.Configuration;
import org.hibernate.cfg.NamingStrategy;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.hibernate.tool.hbm2ddl.SchemaExport.Type;
import org.hibernate.tool.hbm2ddl.Target;
import org.scannotation.AnnotationDB;

/**
 * Goal which extracts the hibernate-mapping-configuration and
 * exports an according SQL-database-schema.
 *
 * @goal export
 * @phase process-classes
 * @threadSafe
 * @requiresDependencyResolution runtime
 */
public class Hbm2DdlMojo extends AbstractMojo {
    public final static String EXPORT_SKIPPED_PROPERTY = "hibernate.export.skipped";

    public final static String DRIVER_CLASS = "hibernate.connection.driver_class";
    public final static String URL = "hibernate.connection.url";
    public final static String USERNAME = "hibernate.connection.username";
    public final static String PASSWORD = "hibernate.connection.password";
    public final static String DIALECT = "hibernate.dialect";
    public final static String NAMING_STRATEGY = "hibernate.ejb.naming_strategy";

    private final static String MD5S = "schema.md5s";

    /**
     * The maven project.
     * <p>
     * Only needed internally.
     *
     * @parameter property="project"
     * @required
     * @readonly
     */
    private MavenProject project;

    /**
     * Build-directory.
     * <p>
     * Only needed internally.
     *
     * @parameter property="project.build.directory"
     * @required
     * @readonly
     */
    private String buildDirectory;

    /**
     * Classes-Directory to scan.
     * <p>
     * This parameter defaults to the maven build-output-directory for classes.
     * Additonally, all dependencies are scanned for annotated classes.
     *
     * @parameter property="project.build.outputDirectory"
     */
    private String outputDirectory;

    /**
     * Wether to scan test-classes too, or not.
     * <p>
     * If this parameter is set to <code>true</code> the test-classes of the
     * artifact will be scanned for hibernate-annotated classes additionally.
     *
     * @parameter property="hibernate.export.scan_testclasses" default-value="false"
     */
    private boolean scanTestClasses;

    /**
     * Test-Classes-Directory to scan.
     * <p>
     * This parameter defaults to the maven build-output-directory for
     * test-classes.
     * <p>
     * This parameter is only used, when <code>scanTestClasses</code> is set
     * to <code>true</code>!
     *
     * @parameter property="project.build.testOutputDirectory"
     */
    private String testOutputDirectory;

    /**
     * Skip execution
     * <p>
     * If set to <code>true</code>, the execution is skipped.
     * <p>
     * A skipped excecution is signaled via the maven-property
     * <code>${hibernate.export.skipped}</code>.
     * <p>
     * The excecution is skipped automatically, if no modified or newly added
     * annotated classes are found and the dialect was not changed.
     *
     * @parameter property="maven.test.skip" default-value="false"
     */
    private boolean skip;

    /**
     * Force execution
     * <p>
     * Force execution, even if no modified or newly added annotated classes
     * where found and the dialect was not changed.
     * <p>
     * <code>skip</code> takes precedence over <code>force</code>.
     *
     * @parameter property="hibernate.export.force" default-value="false"
     */
    private boolean force;

    /**
     * SQL-Driver name.
     *
     * @parameter property="hibernate.connection.driver_class"
     */
    private String driverClassName;

    /**
     * Database URL.
     *
     * @parameter property="hibernate.connection.url"
     */
    private String url;

    /**
     * Database username
     *
     * @parameter property="hibernate.connection.username"
     */
    private String username;

    /**
     * Database password
     *
     * @parameter property="hibernate.connection.password"
     */
    private String password;

    /**
     * Hibernate dialect.
     *
     * @parameter property="hibernate.dialect"
     */
    private String hibernateDialect;

    /**
     * Hibernate Naming Strategy
     * @parameter property="hibernate.ejb.naming_strategy"
     * @author nicus
     */
    private String hibernateNamingStrategy;

    /**
     * Path to Hibernate configuration file.
     *
     * @parameter default-value="${project.build.outputDirectory}/hibernate.properties"
     */
    private String hibernateProperties;

    /**
     * Target of execution:
     * <ul>
     *   <li><strong>NONE</strong> do nothing - just validate the configuration (forces excecution, signals skip)</li>
     *   <li><strong>EXPORT</strong> create database (<strong>DEFAULT!</strong>. forces excecution, signals skip)</li>
     *   <li><strong>SCRIPT</strong> export schema to SQL-script</li>
     *   <li><strong>BOTH</strong></li>
     * </ul>
     *
     * @parameter property="hibernate.export.target" default-value="EXPORT"
     */
    private String target;

    /**
     * Type of execution.
     * <ul>
     *   <li><strong>NONE</strong> do nothing - just validate the configuration</li>
     *   <li><strong>CREATE</strong> create database-schema</li>
     *   <li><strong>DROP</strong> drop database-schema</li>
     *   <li><strong>BOTH</strong> (<strong>DEFAULT!</strong>)</li>
     * </ul>
     *
     * @parameter property="hibernate.export.type" default-value="BOTH"
     */
    private String type;

    /**
     * Output file.
     *
     * @parameter property="hibernate.export.schema.filename" default-value="${project.build.directory}/schema.sql"
     */
    private String outputFile;

    /**
     * Delimiter in output-file.
     *
     * @parameter property="hibernate.export.schema.delimiter" default-value=";"
     */
    private String delimiter;

    /**
     * Format output-file.
     *
     * @parameter property="hibernate.export.schema.format" default-value="true"
     */
    private boolean format;

    @Override
    public void execute() throws MojoFailureException, MojoExecutionException {
        if (skip) {
            getLog().info("Exectuion of hibernate4-maven-plugin:export was skipped!");
            project.getProperties().setProperty(EXPORT_SKIPPED_PROPERTY, "true");
            return;
        }

        File dir = new File(outputDirectory);
        if (!dir.exists())
            throw new MojoExecutionException(
                    "Cannot scan for annotated classes in " + outputDirectory + ": directory does not exist!");

        Map<String, String> md5s;
        boolean modified = false;
        File saved = new File(buildDirectory + File.separator + MD5S);

        if (saved.exists()) {
            try {
                FileInputStream fis = new FileInputStream(saved);
                ObjectInputStream ois = new ObjectInputStream(fis);
                md5s = (HashMap<String, String>) ois.readObject();
                ois.close();
            } catch (Exception e) {
                md5s = new HashMap<String, String>();
                getLog().warn("Cannot read timestamps from saved: " + e);
            }
        } else {
            md5s = new HashMap<String, String>();
            try {
                saved.createNewFile();
            } catch (IOException e) {
                getLog().warn("Cannot create saved for timestamps: " + e);
            }
        }

        ClassLoader classLoader = null;
        try {
            getLog().debug("Creating ClassLoader for project-dependencies...");
            List<String> classpathFiles = project.getCompileClasspathElements();
            if (scanTestClasses)
                classpathFiles.addAll(project.getTestClasspathElements());
            URL[] urls = new URL[classpathFiles.size()];
            for (int i = 0; i < classpathFiles.size(); ++i) {
                getLog().debug("Dependency: " + classpathFiles.get(i));
                urls[i] = new File(classpathFiles.get(i)).toURI().toURL();
            }
            classLoader = new URLClassLoader(urls, getClass().getClassLoader());
        } catch (Exception e) {
            getLog().error("Error while creating ClassLoader!", e);
            throw new MojoExecutionException(e.getMessage());
        }

        Set<Class<?>> classes = new TreeSet<Class<?>>(new Comparator<Class<?>>() {
            @Override
            public int compare(Class<?> a, Class<?> b) {
                return a.getName().compareTo(b.getName());
            }
        });

        try {
            AnnotationDB db = new AnnotationDB();
            getLog().info("Scanning directory " + outputDirectory + " for annotated classes...");
            URL dirUrl = dir.toURI().toURL();
            db.scanArchives(dirUrl);
            if (scanTestClasses) {
                dir = new File(testOutputDirectory);
                if (!dir.exists())
                    throw new MojoExecutionException("Cannot scan for annotated test-classes in "
                            + testOutputDirectory + ": directory does not exist!");
                getLog().info("Scanning directory " + testOutputDirectory + " for annotated classes...");
                dirUrl = dir.toURI().toURL();
                db.scanArchives(dirUrl);
            }

            Set<String> classNames = new HashSet<String>();
            if (db.getAnnotationIndex().containsKey(Entity.class.getName()))
                classNames.addAll(db.getAnnotationIndex().get(Entity.class.getName()));
            if (db.getAnnotationIndex().containsKey(MappedSuperclass.class.getName()))
                classNames.addAll(db.getAnnotationIndex().get(MappedSuperclass.class.getName()));
            if (db.getAnnotationIndex().containsKey(Embeddable.class.getName()))
                classNames.addAll(db.getAnnotationIndex().get(Embeddable.class.getName()));

            MessageDigest digest = java.security.MessageDigest.getInstance("MD5");
            for (String name : classNames) {
                Class<?> annotatedClass = classLoader.loadClass(name);
                classes.add(annotatedClass);
                InputStream is = annotatedClass.getResourceAsStream(annotatedClass.getSimpleName() + ".class");
                byte[] buffer = new byte[1024 * 4]; // copy data in 4MB-chunks
                int i;
                while ((i = is.read(buffer)) > -1)
                    digest.update(buffer, 0, i);
                is.close();
                byte[] bytes = digest.digest();
                BigInteger bi = new BigInteger(1, bytes);
                String newMd5 = String.format("%0" + (bytes.length << 1) + "x", bi);
                String oldMd5 = !md5s.containsKey(name) ? "" : md5s.get(name);
                if (!newMd5.equals(oldMd5)) {
                    getLog().debug("Found new or modified annotated class: " + name);
                    modified = true;
                    md5s.put(name, newMd5);
                } else {
                    getLog().debug(oldMd5 + " -> class unchanged: " + name);
                }
            }
        } catch (ClassNotFoundException e) {
            getLog().error("Error while adding annotated classes!", e);
            throw new MojoExecutionException(e.getMessage());
        } catch (Exception e) {
            getLog().error("Error while scanning!", e);
            throw new MojoFailureException(e.getMessage());
        }

        if (classes.isEmpty())
            throw new MojoFailureException("No annotated classes found in directory " + outputDirectory);

        getLog().debug("Detected classes with mapping-annotations:");
        for (Class<?> annotatedClass : classes)
            getLog().debug("  " + annotatedClass.getName());

        Properties properties = new Properties();

        /** Try to read configuration from properties-file */
        try {
            File file = new File(hibernateProperties);
            if (file.exists()) {
                getLog().info("Reading properties from file " + hibernateProperties + "...");
                properties.load(new FileInputStream(file));
            } else
                getLog().info("No hibernate-properties-file found! (Checked path: " + hibernateProperties + ")");
        } catch (IOException e) {
            getLog().error("Error while reading properties!", e);
            throw new MojoExecutionException(e.getMessage());
        }

        /** Overwrite values from propertie-file or set, if given */
        if (driverClassName != null) {
            if (properties.containsKey(DRIVER_CLASS))
                getLog().debug("Overwriting property " + DRIVER_CLASS + "=" + properties.getProperty(DRIVER_CLASS)
                        + " with the value " + driverClassName);
            else
                getLog().debug("Using the value " + driverClassName);
            properties.setProperty(DRIVER_CLASS, driverClassName);
        }
        if (url != null) {
            if (properties.containsKey(URL))
                getLog().debug("Overwriting property " + URL + "=" + properties.getProperty(URL)
                        + " with the value " + url);
            else
                getLog().debug("Using the value " + url);
            properties.setProperty(URL, url);
        }
        if (username != null) {
            if (properties.containsKey(USERNAME))
                getLog().debug("Overwriting property " + USERNAME + "=" + properties.getProperty(USERNAME)
                        + " with the value " + username);
            else
                getLog().debug("Using the value " + username);
            properties.setProperty(USERNAME, username);
        }
        if (password != null) {
            if (properties.containsKey(PASSWORD))
                getLog().debug("Overwriting property " + PASSWORD + "=" + properties.getProperty(PASSWORD)
                        + " with the value " + password);
            else
                getLog().debug("Using the value " + password);
            properties.setProperty(PASSWORD, password);
        }
        if (hibernateDialect != null) {
            if (properties.containsKey(DIALECT))
                getLog().debug("Overwriting property " + DIALECT + "=" + properties.getProperty(DIALECT)
                        + " with the value " + hibernateDialect);
            else
                getLog().debug("Using the value " + hibernateDialect);
            properties.setProperty(DIALECT, hibernateDialect);
        }
        if (hibernateNamingStrategy != null) {
            if (properties.contains(NAMING_STRATEGY))
                getLog().debug("Overwriting property " + NAMING_STRATEGY + "="
                        + properties.getProperty(NAMING_STRATEGY) + " with the value " + hibernateNamingStrategy);
            else
                getLog().debug("Using the value " + hibernateNamingStrategy);
            properties.setProperty(NAMING_STRATEGY, hibernateNamingStrategy);
        }

        /** The generated SQL varies with the dialect! */
        if (md5s.containsKey(DIALECT)) {
            String dialect = properties.getProperty(DIALECT);
            if (md5s.get(DIALECT).equals(dialect))
                getLog().debug("SQL-dialect unchanged.");
            else {
                getLog().debug("SQL-dialect changed: " + dialect);
                modified = true;
                md5s.put(DIALECT, dialect);
            }
        } else {
            modified = true;
            md5s.put(DIALECT, properties.getProperty(DIALECT));
        }

        if (properties.isEmpty()) {
            getLog().error("No properties set!");
            throw new MojoFailureException("Hibernate-Configuration is missing!");
        }

        Configuration config = new Configuration();
        config.setProperties(properties);

        if (properties.containsKey(NAMING_STRATEGY)) {
            String namingStrategy = properties.getProperty(NAMING_STRATEGY);
            getLog().debug("Explicitly set NamingStrategy: " + namingStrategy);
            try {
                @SuppressWarnings("unchecked")
                Class<NamingStrategy> namingStrategyClass = (Class<NamingStrategy>) Class.forName(namingStrategy);
                config.setNamingStrategy(namingStrategyClass.newInstance());
            } catch (Exception e) {
                getLog().error("Error setting NamingStrategy", e);
                throw new MojoExecutionException(e.getMessage());
            }
        }

        getLog().debug("Adding annotated classes to hibernate-mapping-configuration...");
        for (Class<?> annotatedClass : classes) {
            getLog().debug("Class " + annotatedClass);
            config.addAnnotatedClass(annotatedClass);
        }

        Target target = null;
        try {
            target = Target.valueOf(this.target.toUpperCase());
        } catch (IllegalArgumentException e) {
            getLog().error("Invalid value for configuration-option \"target\": " + this.target);
            getLog().error("Valid values are: NONE, SCRIPT, EXPORT, BOTH");
            throw new MojoExecutionException("Invalid value for configuration-option \"target\"");
        }
        Type type = null;
        try {
            type = Type.valueOf(this.type.toUpperCase());
        } catch (IllegalArgumentException e) {
            getLog().error("Invalid value for configuration-option \"type\": " + this.type);
            getLog().error("Valid values are: NONE, CREATE, DROP, BOTH");
            throw new MojoExecutionException("Invalid value for configuration-option \"type\"");
        }

        if (target.equals(Target.SCRIPT) || target.equals(Target.NONE)) {
            project.getProperties().setProperty(EXPORT_SKIPPED_PROPERTY, "true");
        }
        if (!modified && !target.equals(Target.SCRIPT) && !target.equals(Target.NONE) && !force) {
            getLog().info("No modified annotated classes found and dialect unchanged.");
            getLog().info("Skipping schema generation!");
            project.getProperties().setProperty(EXPORT_SKIPPED_PROPERTY, "true");
            return;
        }

        getLog().info("Gathered hibernate-configuration (turn on debugging for details):");
        for (Entry<Object, Object> entry : properties.entrySet())
            getLog().info("  " + entry.getKey() + " = " + entry.getValue());

        Connection connection = null;
        try {
            /**
             * The connection must be established outside of hibernate, because
             * hibernate does not use the context-classloader of the current
             * thread and, hence, would not be able to resolve the driver-class!
             */
            switch (target) {
            case EXPORT:
            case BOTH:
                switch (type) {
                case CREATE:
                case DROP:
                case BOTH:
                    Class driverClass = classLoader.loadClass(properties.getProperty(DRIVER_CLASS));
                    getLog().debug("Registering JDBC-driver " + driverClass.getName());
                    DriverManager.registerDriver(new DriverProxy((Driver) driverClass.newInstance()));
                    getLog().debug("Opening JDBC-connection to " + properties.getProperty(URL) + " as "
                            + properties.getProperty(USERNAME) + " with password "
                            + properties.getProperty(PASSWORD));
                    connection = DriverManager.getConnection(properties.getProperty(URL),
                            properties.getProperty(USERNAME), properties.getProperty(PASSWORD));
                }
            }
        } catch (ClassNotFoundException e) {
            getLog().error("Dependency for driver-class " + properties.getProperty(DRIVER_CLASS) + " is missing!");
            throw new MojoExecutionException(e.getMessage());
        } catch (Exception e) {
            getLog().error("Cannot establish connection to database!");
            Enumeration<Driver> drivers = DriverManager.getDrivers();
            if (!drivers.hasMoreElements())
                getLog().error("No drivers registered!");
            while (drivers.hasMoreElements())
                getLog().debug("Driver: " + drivers.nextElement());
            throw new MojoExecutionException(e.getMessage());
        }

        ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader();
        MavenLogAppender.startPluginLog(this);
        try {
            /**
             * Change class-loader of current thread, so that hibernate can
             * see all dependencies!
             */
            Thread.currentThread().setContextClassLoader(classLoader);

            SchemaExport export = new SchemaExport(config, connection);
            export.setOutputFile(outputFile);
            export.setDelimiter(delimiter);
            export.setFormat(format);
            export.execute(target, type);

            for (Object exception : export.getExceptions())
                getLog().debug(exception.toString());
        } finally {
            /** Stop Log-Capturing */
            MavenLogAppender.endPluginLog(this);

            /** Restore the old class-loader (TODO: is this really necessary?) */
            Thread.currentThread().setContextClassLoader(contextClassLoader);

            /** Close the connection */
            try {
                if (connection != null)
                    connection.close();
            } catch (SQLException e) {
                getLog().error("Error while closing connection: " + e.getMessage());
            }
        }

        /** Write md5-sums for annotated classes to file */
        try {
            FileOutputStream fos = new FileOutputStream(saved);
            ObjectOutputStream oos = new ObjectOutputStream(fos);
            oos.writeObject(md5s);
            oos.close();
            fos.close();
        } catch (Exception e) {
            getLog().error("Cannot write md5-sums to file: " + e);
        }
    }

    /**
     * Needed, because DriverManager won't pick up drivers, that were not
     * loaded by the system-classloader!
     * See:
     * http://stackoverflow.com/questions/288828/how-to-use-a-jdbc-driver-fromodifiedm-an-arbitrary-location
     */
    static final class DriverProxy implements Driver {
        private final Driver target;

        DriverProxy(Driver target) {
            if (target == null)
                throw new NullPointerException();
            this.target = target;
        }

        public java.sql.Driver getTarget() {
            return target;
        }

        @Override
        public boolean acceptsURL(String url) throws SQLException {
            return target.acceptsURL(url);
        }

        @Override
        public java.sql.Connection connect(String url, java.util.Properties info) throws SQLException {
            return target.connect(url, info);
        }

        @Override
        public int getMajorVersion() {
            return target.getMajorVersion();
        }

        @Override
        public int getMinorVersion() {
            return target.getMinorVersion();
        }

        @Override
        public DriverPropertyInfo[] getPropertyInfo(String url, Properties info) throws SQLException {
            return target.getPropertyInfo(url, info);
        }

        @Override
        public boolean jdbcCompliant() {
            return target.jdbcCompliant();
        }

        /**
         * This Method cannot be annotated with @Override, becaus the plugin
         * will not compile then under Java 1.6!
         */
        public Logger getParentLogger() throws SQLFeatureNotSupportedException {
            throw new SQLFeatureNotSupportedException("Not supported, for backward-compatibility with Java 1.6");
        }

        @Override
        public String toString() {
            return "Proxy: " + target;
        }

        @Override
        public int hashCode() {
            return target.hashCode();
        }

        @Override
        public boolean equals(Object obj) {
            if (!(obj instanceof DriverProxy))
                return false;
            DriverProxy other = (DriverProxy) obj;
            return this.target.equals(other.target);
        }
    }
}