HSQLDB example source code file (HsqlProperties.java)

This example HSQLDB source code file (HsqlProperties.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

enumeration, exception, fileaccess, hsqlproperties, hsqlproperties, inputstream, io, no_value_for_key, numberformatexception, numberformatexception, object, properties, properties, string, string, util

The HSQLDB HsqlProperties.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.persist;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.Properties;

import org.hsqldb.Trace;
import org.hsqldb.lib.ArrayUtil;
import org.hsqldb.lib.FileAccess;
import org.hsqldb.lib.FileUtil;
import org.hsqldb.lib.ResourceStreamProvider;
import org.hsqldb.lib.java.JavaSystem;

/**
 * Wrapper for java.util.Properties to limit values to Specific types and
 * allow saving and loading.<p>
 *
 * @author fredt@users
 * @version 1.7.2
 * @since 1.7.0
 */
public class HsqlProperties {

    public static final int NO_VALUE_FOR_KEY = 1;
    protected String        fileName;
    protected Properties    stringProps;
    protected int[]         errorCodes = new int[0];
    protected String[]      errorKeys  = new String[0];
    protected boolean       resource   = false;
    protected FileAccess    fa;

    public HsqlProperties() {
        stringProps = new Properties();
        fileName    = null;
    }

    public HsqlProperties(String name) {

        stringProps = new Properties();
        fileName    = name;
        fa          = FileUtil.getDefaultInstance();
    }

    public HsqlProperties(String name, FileAccess accessor, boolean b) {

        stringProps = new Properties();
        fileName    = name;
        resource    = b;
        fa          = accessor;
    }

    public HsqlProperties(Properties props) {
        stringProps = props;
    }

    public void setFileName(String name) {
        fileName = name;
    }

    public String setProperty(String key, int value) {
        return setProperty(key, Integer.toString(value));
    }

    public String setProperty(String key, boolean value) {
        return setProperty(key, String.valueOf(value));
    }

    public String setProperty(String key, String value) {
        return (String) stringProps.put(key, value);
    }

    public String setPropertyIfNotExists(String key, String value) {

        value = getProperty(key, value);

        return setProperty(key, value);
    }

    public Properties getProperties() {
        return stringProps;
    }

    public String getProperty(String key) {
        return stringProps.getProperty(key);
    }

    public String getProperty(String key, String defaultValue) {
        return stringProps.getProperty(key, defaultValue);
    }

    public int getIntegerProperty(String key, int defaultValue) {

        String prop = getProperty(key);

        try {
            if (prop != null) {
                defaultValue = Integer.parseInt(prop);
            }
        } catch (NumberFormatException e) {}

        return defaultValue;
    }

    public int getIntegerProperty(String key, int defaultValue, int minimum,
                                  int maximum) {

        String  prop     = getProperty(key);
        boolean badvalue = false;

        try {
            defaultValue = Integer.parseInt(prop);
        } catch (NumberFormatException e) {}

        if (defaultValue < minimum) {
            defaultValue = minimum;
            badvalue     = true;
        } else if (defaultValue > maximum) {
            defaultValue = maximum;
            badvalue     = true;
        }

        return defaultValue;
    }

    /**
     * Choice limited to values list, defaultValue must be in the values list.
     */
    public int getIntegerProperty(String key, int defaultValue, int[] values) {

        String prop  = getProperty(key);
        int    value = defaultValue;

        try {
            if (prop != null) {
                value = Integer.parseInt(prop);
            }
        } catch (NumberFormatException e) {}

        if (ArrayUtil.find(values, value) == -1) {
            return defaultValue;
        }

        return value;
    }

    public boolean isPropertyTrue(String key) {
        return isPropertyTrue(key, false);
    }

    public boolean isPropertyTrue(String key, boolean defaultValue) {

        String value = stringProps.getProperty(key);

        if (value == null) {
            return defaultValue;
        }

        return value.toLowerCase().equals("true");
    }

    public void removeProperty(String key) {
        stringProps.remove(key);
    }

    public void addProperties(Properties props) {

        if (props == null) {
            return;
        }

        Enumeration keys = props.keys();

        while (keys.hasMoreElements()) {
            Object key = keys.nextElement();

            this.stringProps.put(key, props.get(key));
        }
    }

    public void addProperties(HsqlProperties props) {

        if (props == null) {
            return;
        }

        addProperties(props.stringProps);
    }

// oj@openoffice.org
    public boolean checkFileExists() throws IOException {

        String propFilename = fileName + ".properties";

        return fa.isStreamElement(propFilename);
    }

    public boolean load() throws Exception {

        if (!checkFileExists()) {
            return false;
        }

        if (fileName == null || fileName.length() == 0) {
            throw new FileNotFoundException(
                Trace.getMessage(Trace.HsqlProperties_load));
        }

        InputStream fis           = null;
        String      propsFilename = fileName + ".properties";

// oj@openoffice.org
        try {
            fis = resource ? ResourceStreamProvider.getResourceAsStream(propsFilename)
                           : fa.openInputStreamElement(propsFilename);

            stringProps.load(fis);
        } finally {
            if (fis != null) {
                fis.close();
            }
        }

        return true;
    }

    /**
     *  Saves the properties.
     */
    public void save() throws Exception {

        if (fileName == null || fileName.length() == 0) {
            throw new java.io.FileNotFoundException(
                Trace.getMessage(Trace.HsqlProperties_load));
        }

        String filestring = fileName + ".properties";

        save(filestring);
    }

    /**
     *  Saves the properties using JDK2 method if present, otherwise JDK1.
     */
    public void save(String fileString) throws Exception {

// oj@openoffice.org
        fa.createParentDirs(fileString);

        OutputStream        fos = fa.openOutputStreamElement(fileString);
        FileAccess.FileSync outDescriptor = fa.getFileSync(fos);

        JavaSystem.saveProperties(
            stringProps,
            HsqlDatabaseProperties.PRODUCT_NAME + " "
            + HsqlDatabaseProperties.THIS_FULL_VERSION, fos);
        fos.flush();
        outDescriptor.sync();
        fos.close();

        return;
    }

    /**
     * Adds the error code and the key to the list of errors. This list
     * is populated during construction or addition of elements and is used
     * outside this class to act upon the errors.
     */
    private void addError(int code, String key) {

        errorCodes = (int[]) ArrayUtil.resizeArray(errorCodes,
                errorCodes.length + 1);
        errorKeys = (String[]) ArrayUtil.resizeArray(errorKeys,
                errorKeys.length + 1);
        errorCodes[errorCodes.length - 1] = code;
        errorKeys[errorKeys.length - 1]   = key;
    }

    /**
     * Creates and populates an HsqlProperties Object from the arguments
     * array of a Main method. Properties are in the form of "-key value"
     * pairs. Each key is prefixed with the type argument and a dot before
     * being inserted into the properties Object. <p>
     *
     * "-?" is treated as a key with no value and not inserted.
     */
    public static HsqlProperties argArrayToProps(String[] arg, String type) {

        HsqlProperties props = new HsqlProperties();

        for (int i = 0; i < arg.length; i++) {
            String p = arg[i];

            if (p.startsWith("-?")) {
                props.addError(NO_VALUE_FOR_KEY, p.substring(1));
            } else if (p.charAt(0) == '-') {
                String value = i + 1 < arg.length ? arg[i + 1]
                                                  : "";

                props.setProperty(type + "." + p.substring(1), value);

                i++;
            }
        }

        return props;
    }

    /**
     * Creates and populates a new HsqlProperties Object using a string
     * such as "key1=value1;key2=value2". <p>
     *
     * The string that represents the = sign above is specified as pairsep
     * and the one that represents the semicolon is specified as delimiter,
     * allowing any string to be used for either.<p>
     *
     * Leading / trailing spaces around the keys and values are discarded.<p>
     *
     * The string is parsed by (1) subdividing into segments by delimiter
     * (2) subdividing each segment in two by finding the first instance of
     * the pairsep (3) trimming each pair of segments from step 2 and
     * inserting into the properties object.<p>
     *
     * Each key is prefixed with the type argument and a dot before being
     * inserted.<p>
     *
     * Any key without a value is added to the list of errors.
     */
    public static HsqlProperties delimitedArgPairsToProps(String s,
            String pairsep, String dlimiter, String type) {

        HsqlProperties props       = new HsqlProperties();
        int            currentpair = 0;

        while (true) {
            int nextpair = s.indexOf(dlimiter, currentpair);

            if (nextpair == -1) {
                nextpair = s.length();
            }

            // find value within the segment
            int valindex = s.substring(0, nextpair).indexOf(pairsep,
                                       currentpair);

            if (valindex == -1) {
                props.addError(NO_VALUE_FOR_KEY,
                               s.substring(currentpair, nextpair).trim());
            } else {
                String key = s.substring(currentpair, valindex).trim();
                String value = s.substring(valindex + pairsep.length(),
                                           nextpair).trim();

                if (type != null) {
                    key = type + "." + key;
                }

                props.setProperty(key, value);
            }

            if (nextpair == s.length()) {
                break;
            }

            currentpair = nextpair + dlimiter.length();
        }

        return props;
    }

    public Enumeration propertyNames() {
        return stringProps.propertyNames();
    }

    public boolean isEmpty() {
        return stringProps.isEmpty();
    }

    public String[] getErrorKeys() {
        return errorKeys;
    }
/*
    public static void main(String[] argv) {

        HsqlProperties props1 = delimitedArgPairsToProps("-dbname.0", "=",
            ";", "server");
        HsqlProperties props2 = delimitedArgPairsToProps(
            "filename.cvs;a=123 ;  b=\\delta ;c= another; derrorkey;", "=",
            ";", "textdb");
    }
*/
}