HSQLDB example source code file (RCData.java)

This example HSQLDB source code file (RCData.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - HSQLDB tags/keywords

connection, default_jdbc_driver, exception, exception, illegalargumentexception, illegalargumentexception, io, ioexception, jdbc, net, network, rcdata, rcdata, sql, sqlexception, string, string, transaction_read_committed, transaction_serializable, util

The HSQLDB RCData.java source code

/* Copyright (c) 2001-2008, The HSQL Development Group
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the HSQL Development Group nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL HSQL DEVELOPMENT GROUP, HSQLDB.ORG,
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


package org.hsqldb.lib;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.net.MalformedURLException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;
import java.util.StringTokenizer;

/* $Id: RCData.java 1153 2009-02-14 04:14:23Z unsaved $ */

/**
 * Manages all the details we need to connect up to database(s),
 * in a declarative way.
 * <P/>
 * The file <CODE>src/org/hsqldb/sample/SqlFileEmbedder.java
 * in the HSQLDB distribution provides an example of how to use RCData for your
 * own programs.
 *
 * @see <a href="../../../../util-guide/sqltool-chapt.html#sqltool_auth-sect"
 *      target="guide">
 *     The RC File section of the HyperSQL Utilities Guide</a>
 * @see org.hsqldb.sample.SqlFileEmbedder
 * @author Blaine Simpson (blaine dot simpson at admc dot com)
 */
public class RCData {

    public static final String DEFAULT_JDBC_DRIVER   = "org.hsqldb.jdbcDriver";
    private String             defaultJdbcDriverName = DEFAULT_JDBC_DRIVER;

    public void setDefaultJdbcDriver(String defaultJdbcDriverName) {
        this.defaultJdbcDriverName = defaultJdbcDriverName;
    }

    public String getDefaultJdbcDriverName() {
        return defaultJdbcDriverName;
    }

    /**
     * DISABLED DUE TO SECURITY CONCERNS.
     * Just for testing and debugging.
     *
     * N.b. this echoes passwords!
    public void report() {
        System.err.println("urlid: " + id + ", url: " + url + ", username: "
                           + username + ", password: " + password);
    }
     */

    /**
     * Creates a RCDataObject by looking up the given key in the
     * given authentication file.
     *
     * @param dbKey Key to look up in the file.
     *              If null, then will echo all urlids in the file to stdout.
     * @param file File containing the authentication information.
     */
    public RCData(File file, String dbKey) throws Exception {

        if (file == null) {
            throw new IllegalArgumentException("RC file name not specified");
        }

        if (!file.canRead()) {
            throw new IOException("Please set up authentication file '" + file
                                  + "'");
        }

        // System.err.println("Using RC file '" + file + "'");
        StringTokenizer tokenizer = null;
        boolean         thisone   = false;
        String          s;
        String          keyword, value;
        int             linenum = 0;
        BufferedReader  br      = new BufferedReader(new FileReader(file));

        while ((s = br.readLine()) != null) {
            ++linenum;

            s = s.trim();

            if (s.length() == 0) {
                continue;
            }

            if (s.charAt(0) == '#') {
                continue;
            }

            tokenizer = new StringTokenizer(s);

            if (tokenizer.countTokens() == 1) {
                keyword = tokenizer.nextToken();
                value   = "";
            } else if (tokenizer.countTokens() > 1) {
                keyword = tokenizer.nextToken();
                value   = tokenizer.nextToken("").trim();
            } else {
                try {
                    br.close();
                } catch (IOException e) {
                    // Can only report on so many errors at one time
                }

                throw new Exception("Corrupt line " + linenum + " in '" + file
                                    + "':  " + s);
            }

            if (dbKey == null) {
                if (keyword.equals("urlid")) {
                    System.out.println(value);
                }

                continue;
            }

            if (keyword.equals("urlid")) {
                if (value.equals(dbKey)) {
                    if (id == null) {
                        id      = dbKey;
                        thisone = true;
                    } else {
                        try {
                            br.close();
                        } catch (IOException e) {
                            // Can only report on so many errors at one time
                        }

                        throw new Exception("Key '" + dbKey + " redefined at"
                                            + " line " + linenum + " in '"
                                            + file);
                    }
                } else {
                    thisone = false;
                }

                continue;
            }

            if (thisone) {
                if (keyword.equals("url")) {
                    url = value;
                } else if (keyword.equals("username")) {
                    username = value;
                } else if (keyword.equals("driver")) {
                    driver = value;
                } else if (keyword.equals("charset")) {
                    charset = value;
                } else if (keyword.equals("truststore")) {
                    truststore = value;
                } else if (keyword.equals("password")) {
                    password = value;
                } else if (keyword.equals("transiso")) {
                    ti = value;
                } else if (keyword.equals("libpath")) {
                    libpath = value;
                } else {
                    try {
                        br.close();
                    } catch (IOException e) {
                        // Can only report on so many errors at one time
                    }

                    throw new Exception("Bad line " + linenum + " in '" + file
                                        + "':  " + s);
                }
            }
        }

        br.close();

        if (dbKey == null) {
            return;
        }

        if (url == null) {
            throw new Exception("url not set " + "for '" + dbKey
                                + "' in file '" + file + "'");
        }

        if (libpath != null) {
            throw new IllegalArgumentException(
                "Sorry, 'libpath' not supported yet");
        }
    }

    /**
     * Convenience constructor for backward compatibility.
     *
     * @see #RCData(String,String,String,String,String,String,String,String)
     */
    public RCData(String id, String url, String username, String password,
                  String driver, String charset,
                  String truststore) throws Exception {
        this(id, url, username, password, driver, charset, truststore, null);
    }

    /**
     * Wrapper for unset Transaction Isolation.
     */
    public RCData(String id, String url, String username, String password,
                  String driver, String charset, String truststore,
                  String libpath) throws Exception {
        this(id, url, username, password, driver, charset, truststore,
                libpath, null);
    }

    /**
     * <p>Creates a new RCData object.
     *
     * <p>The parameters driver, charset, truststore, and libpath are optional.
     * Setting these parameters to <code>NULL will set them to their
     * default values.
     *
     * @param id The identifier for these connection settings
     * @param url The URL of the database to connect to
     * @param username The username to log in as
     * @param password The password of the username
     * @param driver The JDBC driver to use
     * @param charset The character set to use
     * @param truststore The trust store to use
     * @param libpath The JDBC library to add to CLASSPATH
     * @throws Exception if the a non-optional parameter is set to <code>NULL
     */
    public RCData(String id, String url, String username, String password,
                  String driver, String charset, String truststore,
                  String libpath, String ti) throws Exception {

        this.id         = id;
        this.url        = url;
        this.username   = username;
        this.password   = password;
        this.ti         = ti;
        this.driver     = driver;
        this.charset    = charset;
        this.truststore = truststore;
        this.libpath    = libpath;

        if (libpath != null) {
            throw new IllegalArgumentException(
                "Sorry, 'libpath' not supported yet");
        }

        if (id == null || url == null) {
            throw new Exception("id or url was not set");
        }
    }

    /* Purposefully not using JavaBean paradigm so that these fields can
     * be used as a traditional, public DO */
    public String id         = null;
    public String url        = null;
    public String username   = null;
    public String password   = null;
    public String ti         = null;
    public String driver     = null;
    public String charset    = null;
    public String truststore = null;
    public String libpath    = null;

    /**
     * Gets a JDBC Connection using the data of this RCData object.
     *
     * @return New JDBC Connection
     */
    public Connection getConnection()
    throws ClassNotFoundException, SQLException, MalformedURLException {
        return getConnection(null, null, null);
    }

    /**
     * Gets a JDBC Connection using the data of this RCData object with
     * specified override elements
     *
     * @return New JDBC Connection
     */
    public Connection getConnection(String curDriverIn, String curCharsetIn,
                                    String curTrustStoreIn)
                                    throws ClassNotFoundException,
                                           MalformedURLException,
                                           SQLException {

        // Local vars to satisfy compiler warnings
        String curDriver = curDriverIn;
        String curCharset = curCharsetIn;
        String curTrustStore = curTrustStoreIn;

        Properties sysProps = System.getProperties();

        if (curDriver == null) {

            // If explicit driver not specified
            curDriver = ((driver == null) ? DEFAULT_JDBC_DRIVER
                                          : driver);
        }

        if (curCharset == null && charset != null) {
            curCharset = charset;
        }

        if (curTrustStore == null && truststore != null) {
            curTrustStore = truststore;
        }

        if (curCharset == null) {
            sysProps.remove("sqlfile.charset");
        } else {
            sysProps.put("sqlfile.charset", curCharset);
        }

        if (curTrustStore == null) {
            sysProps.remove("javax.net.ssl.trustStore");
        } else {
            sysProps.put("javax.net.ssl.trustStore", curTrustStore);
        }

        String urlString = null;

        try {
            urlString = expandSysPropVars(url);
        } catch (IllegalArgumentException iae) {
            throw new MalformedURLException(iae.getMessage() + " for URL '"
                                            + url + "'");
        }

        String userString = null;

        if (username != null) try {
            userString = expandSysPropVars(username);
        } catch (IllegalArgumentException iae) {
            throw new MalformedURLException(iae.getMessage()
                                            + " for user name '" + username
                                            + "'");
        }

        String passwordString = null;

        if (password != null) try {
            passwordString = expandSysPropVars(password);
        } catch (IllegalArgumentException iae) {
            throw new MalformedURLException(iae.getMessage()
                                            + " for password");
        }

        Class.forName(curDriver);
        // This is not necessary for jdbc:odbc or if class loaded by a
        // service resource file.  Consider checking for that.

        Connection c = (userString == null)
                     ? DriverManager.getConnection(urlString)
                     : DriverManager.getConnection(urlString, userString,
                                                   passwordString);
        if (ti != null) RCData.setTI(c, ti);
        // Would like to verify the setting made by checking
        // c.getTransactionIsolation().  Unfortunately, the spec allows for
        // databases to substitute levels according to some rules, and it's
        // impossible to know what to expect since custom levels are permitted.
        // Debug:
        // System.err.println("TI set to " + ti + "\nPOST: "
        // + SqlTool.tiToString(c.getTransactionIsolation()));

        return c;
    }

    static public String expandSysPropVars(String inString) {

        String outString = new String(inString);
        int    varOffset, varEnd;
        String varVal, varName;

        while (true) {

            // Recursive substitution for ${x} variables.
            varOffset = outString.indexOf("${");

            if (varOffset < 0) {
                break;
            }

            varEnd = outString.indexOf('}', varOffset + 2);

            if (varEnd < 0) {
                break;
            }

            varName = outString.substring(varOffset + 2, varEnd);

            if (varName.length() < 1) {
                throw new IllegalArgumentException("Bad variable setting");
            }

            varVal = System.getProperty(varName);

            if (varVal == null) {
                throw new IllegalArgumentException(
                    "No Java system property with name '" + varName + "'");
            }

            outString = outString.substring(0, varOffset) + varVal
                        + outString.substring(varEnd + 1);
        }

        return outString;
    }

    static public void setTI(Connection c, String tiString)
            throws SQLException {
        int i = -1;
        if (tiString.equals("TRANSACTION_READ_UNCOMMITTED"))
            i = Connection.TRANSACTION_READ_UNCOMMITTED;
        if (tiString.equals("TRANSACTION_READ_COMMITTED"))
            i = Connection.TRANSACTION_READ_COMMITTED;
        if (tiString.equals("TRANSACTION_REPEATABLE_READ"))
            i = Connection.TRANSACTION_REPEATABLE_READ;
        if (tiString.equals("TRANSACTION_SERIALIZABLE"))
            i = Connection.TRANSACTION_SERIALIZABLE;
        if (tiString.equals("TRANSACTION_NONE"))
            i = Connection.TRANSACTION_NONE;
        if (i < 0) {
            throw new SQLException(
                    "Trans. isol. value not supported by "
                    + RCData.class.getName() + ": " + tiString);
        }
        c.setTransactionIsolation(i);
    }

    /**
     * Return String for numerical java.sql.Connection Transaction level.
     *
     * Returns null, since DB implementations are free to provide
     * their own transaction isolation levels.
     */
    static public String tiToString(int ti) {
        switch (ti) {
            case Connection.TRANSACTION_READ_UNCOMMITTED:
                return "TRANSACTION_READ_UNCOMMITTED";
            case Connection.TRANSACTION_READ_COMMITTED:
                return "TRANSACTION_READ_COMMITTED";
            case Connection.TRANSACTION_REPEATABLE_READ:
                return "TRANSACTION_REPEATABLE_READ";
            case Connection.TRANSACTION_SERIALIZABLE:
                return "TRANSACTION_SERIALIZABLE";
            case Connection.TRANSACTION_NONE:
                return "TRANSACTION_NONE";
        }
        return "Custom Transaction Isolation numerical value: " + ti;
    }
}