Sorts a property list and turns the sorted list into a string. : Properties « Collections « Java Tutorial

import java.util.Enumeration;
import java.util.Properties;


   Derby - Class org.apache.derby.iapi.util.PropertyUtil

   Licensed to the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for additional information regarding copyright ownership.
   The ASF licenses this file to you 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

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   See the License for the specific language governing permissions and
   limitations under the License.


public class Main {

   * Sorts a property list and turns the sorted list into a string.
   * @param  list  property list to sort
   * @return a string version of the sorted list
 public  static  String  sortProperties( Properties list )
   // stringify them with no indentation
   return sortProperties(list, null);
   * Sorts property list and print out each key=value pair prepended with 
   * specific indentation.  If indent is null, do not prepend with
   * indentation. 
   * The output string shows up in two styles, style 1 looks like
   * { key1=value1, key2=value2, key3=value3 }
   * style 2 looks like
   *    key1=value1
   *    key2=value2
   *    key3=value3
   * where indent goes between the new line and the keys
   * To get style 1, pass in a null indent
   * To get sytle 2, pass in non-null indent (whatever you want to go before
   * the key value)
  public  static  String  sortProperties( Properties list, String indent )
    int       size = list == null ? 0 : list.size();
    int       count = 0;
    String[]    array = new String[size];
    String      key;
    String      value;
    StringBuffer  buffer;

    // Calculate the number of properties in the property list and
    // build an array of all the property names.
    // We need to go thru the enumeration because Properties has a
    // recursive list of defaults.
    if (list != null)
      for (Enumeration propertyNames = list.propertyNames();
         propertyNames.hasMoreElements(); )
        if (count == size)
          // need to expand the array
          size = size*2;
          String[] expandedArray = new String[size];
          System.arraycopy(array, 0, expandedArray, 0, count);
          array = expandedArray;
        key = (String) propertyNames.nextElement();
        array[ count++ ] = key;

      // now sort the array
      java.util.Arrays.sort(array, 0, count);

    // now stringify the array
    buffer = new StringBuffer();
    if (indent == null)
      buffer.append( "{ " );

    for ( int ictr = 0; ictr < count; ictr++ )
      if ( ictr > 0 && indent == null)
        buffer.append( ", " );

      key = array[ ictr ];

      if (indent != null)
        buffer.append( indent );

      buffer.append( key ); buffer.append( "=" );

      value = list.getProperty( key, "MISSING_VALUE" );
      buffer.append( value );

      if (indent != null)
        buffer.append( "\n" );

    if (indent == null)
      buffer.append( " }" );

    return  buffer.toString();


9.34.1.Setting and Getting Elements
9.34.2.using properties
9.34.3.Getting property by String key value
9.34.4.Getting a key List from Properties
9.34.5.Loading and Saving properties
9.34.6.Use store() to save the properties
9.34.7.List Properties to a print stream or print writer
9.34.8.Using Enumeration to loop through Properties
9.34.9.Put value to a Property list.
9.34.10.Sort Properties when saving
9.34.11.Sorts a property list and turns the sorted list into a string.
9.34.12.Sorts property list and print out each key=value pair prepended with specific indentation.
9.34.13.Load a properties file in the classpath
9.34.14.A Properties file stored in a JAR can be loaded this way
9.34.15.Load a properties file in the startup directory
9.34.16.Have a multi-line value in a properties file
9.34.17.Use XML with Properties
9.34.18.Store properties as XML file
9.34.19.Getting and Setting Properties
9.34.20.Convert a Properties list into a map.
9.34.21.To read a Properties file via an Applet
9.34.22.Read system property as an integer
9.34.23.Read a set of properties from the received input stream, strip off any excess white space that exists in those property values,
9.34.24.Property access utility methods
9.34.25.An utility class to ease up using property-file resource bundles.
9.34.26.Copy a set of properties from one Property to another.
9.34.27.Create Properties from String array
9.34.28.Gets strong-type-value property from a standard Properties
9.34.29.Merge Properties Into Map
9.34.30.Property Loader
9.34.31.Returns a Properties object matching the given node
9.34.32.The properties iterator iterates over a set of enumerated properties.
9.34.33.Use a default property list.