org.eclipse.emf.teneo.test.stores.PgsqlTestDatabaseAdapter.java Source code

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Here is the source code for org.eclipse.emf.teneo.test.stores.PgsqlTestDatabaseAdapter.java

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/**
 * <copyright>
 *
 * Copyright (c) 2005, 2006, 2007, 2008 Springsite BV (The Netherlands) and others
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   Martin Taal
 * </copyright>
 *
 * $Id: PgsqlTestDatabaseAdapter.java,v 1.5 2008/07/13 13:13:39 mtaal Exp $
 */

package org.eclipse.emf.teneo.test.stores;

import java.sql.Connection;
import java.sql.Driver;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.Properties;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.eclipse.emf.teneo.test.StoreTestException;

/**
 * Test database adapter for postgressql. Overrides the database create and drop actions because
 * these require the database name in the url.
 * 
 * The specific issue with the test environment was that at start and cleanup of the test (create
 * and drop of the database), postgresql apparently does not release closed connections quick
 * enough. Therefore create or drop database failed sometimes. Therefore a very rough workaround has
 * been implemented, i.e. the drop/create is retried a number of times before failing.
 * 
 * @author <a href="mailto:mtaal@elver.org">Martin Taal</a>
 * @version $Revision: 1.5 $
 */

public class PgsqlTestDatabaseAdapter extends BaseTestDatabaseAdapter {
    /** The logger */
    private static Log log = LogFactory.getLog(PgsqlTestDatabaseAdapter.class);

    /** The number of tries a create database or drop database is run before giving up */
    private static int NO_TRIES = 20;

    /** The amount of milliseconds to wait for postgres to nicely clean up connections */
    // private static long WAIT_TIME = 10000;
    /** Sets the dbName */
    @Override
    public void setDbName(String databaseName) {
        super.setDbName(databaseName.toLowerCase());
    }

    /** Drops the database and creates a new one */
    @Override
    public void createDatabase() {
        try {
            log.info("Creating database: " + logInfo);

            final Driver driver = (Driver) Class.forName(dbDriver).newInstance();
            Properties info = new Properties();
            info.put("user", dbUser);
            info.put("password", dbPwd);
            Connection conn = null;
            Statement stmt = null;
            try {
                final String useUrl = dbUrl + "template1";
                conn = driver.connect(useUrl, info);
                if (!databaseExists(conn)) {
                    int tries = 0;
                    while (true) {
                        try {
                            tries++;
                            stmt = conn.createStatement();
                            stmt.execute("CREATE DATABASE " + dbName + ";");
                            // conn.commit();
                            return;
                        } catch (Exception e) {
                            Thread.sleep(500);
                            log.warn("Exception (" + e.getMessage() + ") while creating database (" + getDbName()
                                    + "), num of tries: " + tries + ", the create database gives up at: "
                                    + NO_TRIES);
                            // log.warn("Waiting for " + WAIT_TIME +
                            // " milli seconds on postgresql to release connections");
                            // wait(WAIT_TIME);
                            if (tries == NO_TRIES) {
                                throw e;
                            }
                        } finally {
                            if (stmt != null) {
                                stmt.close();
                            }
                            if (conn != null) {
                                conn.close();
                            }
                            conn = driver.connect(useUrl, info);
                        }
                    }
                }
            } finally {
                if (stmt != null) {
                    stmt.close();
                }
                if (conn != null) {
                    conn.close();
                }
            }
        } catch (Exception e) {
            throw new StoreTestException("Exception while creating database: " + logInfo, e);
        }
    }

    /**
     * Drops the database, uses the conn.getMetaData().getCatalogs() method to determine if the
     * database already exists. This should be supported by the database driver.
     */
    @Override
    public void dropDatabase() {
        try {
            final Driver driver = (Driver) Class.forName(dbDriver).newInstance();
            Properties info = new Properties();
            info.put("user", dbUser);
            info.put("password", dbPwd);
            Connection conn = null;
            Statement stmt = null;
            try {
                final String useUrl = dbUrl + "template1";
                conn = driver.connect(useUrl, info);

                // check if the database exists
                stmt = conn.createStatement();
                log.info("Dropping database: " + logInfo);
                ResultSet rs = stmt.executeQuery("SELECT datname FROM pg_database");
                boolean exists = false;
                while (rs.next()) {
                    exists |= dbName.compareTo(rs.getString("datname")) == 0;
                    if (exists) {
                        break;
                    }
                }
                rs.close();
                stmt.close();
                if (exists) {
                    int tries = 0;
                    while (true) {
                        try {
                            tries++;
                            stmt = conn.createStatement();
                            stmt.execute("DROP DATABASE " + dbName + ";");
                            // conn.commit();
                            return;
                        } catch (Exception e) {
                            Thread.sleep(500);
                            log.warn("Exception (" + e.getMessage() + ") while creating database (" + getDbName()
                                    + "), num of tries: " + tries + ", the create database gives up at: "
                                    + NO_TRIES);
                            // log.warn("Waiting for " + WAIT_TIME +
                            // " milli seconds on postgresql to release connections");
                            // wait(WAIT_TIME);
                            if (tries == NO_TRIES) {
                                throw e;
                            }
                        } finally {
                            if (stmt != null) {
                                stmt.close();
                            }
                            if (conn != null) {
                                conn.close();
                            }
                            conn = driver.connect(useUrl, info);
                        }
                    }
                }
                // conn.commit();
                return;
            } finally {
                if (stmt != null) {
                    stmt.close();
                }
                if (conn != null) {
                    conn.close();
                }
            }
        } catch (Exception e) {
            throw new StoreTestException("Exception while dropping database: " + logInfo, e);
        }
    }
}