[#6005] Add DDLDatabase to reverse engineer DDL files

jOOQ-meta-extensions/src/main/java/org/jooq/util/ddl/DDLDatabase.java

@@ -0,0 +1,155 @@
+/*
+ * 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.
+ *
+ * Other licenses:
+ * -----------------------------------------------------------------------------
+ * Commercial licenses for this work are available. These replace the above
+ * ASL 2.0 and offer limited warranties, support, maintenance, and commercial
+ * database integrations.
+ *
+ * For more information, please visit: http://www.jooq.org/licenses
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ */
+package org.jooq.util.ddl;
+
+import static org.jooq.tools.StringUtils.isBlank;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.InputStream;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Scanner;
+
+import org.jooq.DSLContext;
+import org.jooq.Queries;
+import org.jooq.Query;
+import org.jooq.exception.DataAccessException;
+import org.jooq.impl.DSL;
+import org.jooq.tools.JooqLogger;
+import org.jooq.util.SchemaDefinition;
+import org.jooq.util.h2.H2Database;
+
+/**
+ * The DDL database.
+ * <p>
+ * This meta data source parses a set of SQL scripts, translates them to the H2
+ * dialect and runs them on an in-memory H2 database before reverse engineering
+ * the outcome.
+ * <p>
+ * The SQL scripts are located in the <code>scripts</code> scripts property
+ * available from {@link #getProperties()}.
+ *
+ * @author Lukas Eder
+ */
+public class DDLDatabase extends H2Database {
+
+    private static final JooqLogger log = JooqLogger.getLogger(DDLDatabase.class);
+
+    private Connection              connection;
+
+    @SuppressWarnings("serial")
+    @Override
+    protected DSLContext create0() {
+        if (connection == null) {
+            String scripts = getProperties().getProperty("scripts");
+            String encoding = getProperties().getProperty("encoding", "UTF-8");
+
+            if (isBlank(scripts)) {
+                scripts = "";
+                log.warn("No scripts defined", "It is recommended that you provide an explicit script directory to scan");
+            }
+
+            try {
+                connection = DriverManager.getConnection("jdbc:h2:mem:jooq-meta-extensions", "sa", "");
+
+                InputStream in = null;
+                try {
+                    in = DDLDatabase.class.getResourceAsStream(scripts);
+                    if (in != null) {
+                        log.info("Reading from classpath: " + scripts);
+                    }
+                    else {
+                        File file = new File(scripts);
+
+                        if (file.exists()) {
+                            if (file.isFile()) {
+                                log.info("Reading from file: " + scripts);
+                                in = new FileInputStream(file);
+                            }
+                            else if (file.isDirectory()) {
+                                log.warn("Reading from directory not yet supported: " + scripts);
+                            }
+                        }
+                    }
+
+                    if (in != null) {
+                        Scanner s = new Scanner(in, encoding).useDelimiter("\\A");
+                        Queries queries = DSL
+                            .using(connection)
+                            .parser()
+                            .parse(s.hasNext() ? s.next() : "");
+
+                        for (Query query : queries)
+                            query.execute();
+                    }
+                    else {
+                        log.error("Could not find script source : " + scripts);
+                    }
+                }
+                finally {
+                    if (in != null)
+                        try {
+                            in.close();
+                        }
+                        catch (Exception ignore) {}
+                }
+            }
+            catch (Exception e) {
+                throw new DataAccessException("Error while exporting schema", e);
+            }
+        }
+
+        return DSL.using(connection);
+    }
+
+    @Override
+    protected List<SchemaDefinition> getSchemata0() throws SQLException {
+        List<SchemaDefinition> result = new ArrayList<SchemaDefinition>(super.getSchemata0());
+
+        // [#5608] The H2-specific INFORMATION_SCHEMA is undesired in the DDLDatabase's output
+        //         we're explicitly omitting it here for user convenience.
+        Iterator<SchemaDefinition> it = result.iterator();
+        while (it.hasNext())
+            if ("INFORMATION_SCHEMA".equals(it.next().getName()))
+                it.remove();
+
+        return result;
+    }
+}