org.kawanfw.sql.tomcat.util.LinkedProperties.java Source code

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Here is the source code for org.kawanfw.sql.tomcat.util.LinkedProperties.java

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/*
 * This file is part of AceQL. 
 * AceQL: Remote JDBC access over HTTP.                                     
 * Copyright (C) 2015,  KawanSoft SAS
 * (http://www.kawansoft.com). All rights reserved.                                
 *                                                                               
 * AceQL is free software; you can redistribute it and/or                 
 * modify it under the terms of the GNU Lesser General Public                    
 * License as published by the Free Software Foundation; either                  
 * version 2.1 of the License, or (at your option) any later version.            
 *                                                                               
 * AceQL is distributed in the hope that it will be useful,               
 * but WITHOUT ANY WARRANTY; without even the implied warranty of                
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU             
 * Lesser General Public License for more details.                               
 *                                                                               
 * You should have received a copy of the GNU Lesser General Public              
 * License along with this library; if not, write to the Free Software           
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  
 * 02110-1301  USA
 *
 * Any modifications to this file must keep this entire header
 * intact.
 */
package org.kawanfw.sql.tomcat.util;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.Collections;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.Properties;
import java.util.Set;

import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;

/**
 * 
 * @author Nicolas de Pomereu
 * 
 *         Allows to read a properties with property names ordered on insertion
 *         order passed to constructor. (Just for reading, ordered store is not
 *         supported.)
 */

public class LinkedProperties extends Properties {

    /**
     * Generated serial ID
     */
    private static final long serialVersionUID = 6588861237819163772L;

    /** The ordered set of properties */
    private Set<String> orderedPropNames = new LinkedHashSet<String>();

    /**
     * Constructor
     * 
     * @param orderedPropNames
     *            the ordered properties names
     */
    public LinkedProperties(Set<String> orderedPropNames) {
        this.orderedPropNames = orderedPropNames;
    }

    /**
     * Returns a set of keys in this property list where the key and its
     * corresponding value are strings, including distinct keys in the default
     * property list if a key of the same name has not already been found from
     * the main properties list. Properties whose key or value is not of type
     * <tt>String</tt> are omitted.
     * <p>
     * The returned set is not backed by the <tt>Properties</tt> object. Changes
     * to this <tt>Properties</tt> are not reflected in the set, or vice versa.
     *
     * @return a set of keys in this property list where the key and its
     *         corresponding value are strings, including the keys in the
     *         default property list.
     * @see java.util.Properties#defaults
     * @since 1.6
     */
    @Override
    public Set<String> stringPropertyNames() {

        Set<String> orderedPropNamesNew = new LinkedHashSet<String>();

        for (Iterator<String> iterator = orderedPropNames.iterator(); iterator.hasNext();) {
            String propertyName = (String) iterator.next();

            if (super.containsKey(propertyName)) {
                orderedPropNamesNew.add(propertyName);
            }
        }

        return orderedPropNamesNew;
    }

    /*
     * (non-Javadoc)
     * 
     * @see java.util.Properties#propertyNames()
     */
    @Override
    public Enumeration<?> propertyNames() {

        Set<String> orderedPropNamesNew = new LinkedHashSet<String>();

        for (Iterator<String> iterator = orderedPropNames.iterator(); iterator.hasNext();) {
            String propertyName = (String) iterator.next();

            if (super.containsKey(propertyName)) {
                orderedPropNamesNew.add(propertyName);
            }
        }

        return Collections.enumeration(orderedPropNamesNew);

    }

    /*
     * (non-Javadoc)
     * 
     * @see java.util.Hashtable#keys()
     */
    @Override
    public synchronized Enumeration<Object> keys() {

        Set<Object> set = this.keySet();
        return Collections.enumeration(set);
    }

    /*
     * (non-Javadoc)
     * 
     * @see java.util.Hashtable#keySet()
     */
    @Override
    public Set<Object> keySet() {

        Set<Object> set = new LinkedHashSet<Object>();

        for (Iterator<?> iterator = orderedPropNames.iterator(); iterator.hasNext();) {
            Object obj = (Object) iterator.next();
            set.add(obj);
        }

        return set;
    }

    /**
     * Returns the properties name in the order of their position in a file.
     * 
     * @param fileProperties
     *            the file containing the properties
     * @return a Set of Strings backed by a LinkedHashSet ordererd by the
     *         property position in the file
     * @throws IOException
     */
    public static Set<String> getLinkedPropertiesName(File fileProperties) throws IOException {

        Set<String> linkedPropertiesName = new LinkedHashSet<String>();

        BufferedReader bufferedReader = null;

        try {
            bufferedReader = new BufferedReader(new FileReader(fileProperties));

            String line = null;
            while ((line = bufferedReader.readLine()) != null) {

                if (line.isEmpty()) {
                    continue;
                }

                if (line.startsWith("#")) {
                    continue;
                }

                if (line.startsWith("!")) {
                    continue;
                }

                if (!line.contains("=")) {
                    continue;
                }

                line = StringUtils.substringBefore(line, "=");

                line = line.trim();
                linkedPropertiesName.add(line);
            }
        } finally {
            IOUtils.closeQuietly(bufferedReader);
        }

        return linkedPropertiesName;

    }
}