Examples of org.apache.commons.configuration.convert.ListDelimiterHandler

org.apache.commons.configuration.convert.ListDelimiterHandler

Definition of an interface that controls the handling of list delimiters in configuration properties.

{@link org.apache.commons.configuration.AbstractConfiguration AbstractConfiguration} supports list delimiters in property values. If such adelimiter is found, the value actually contains multiple values and has to be split. This is useful for instance for {@link org.apache.commons.configuration.PropertiesConfiguration PropertiesConfiguration}: properties files that have to be compatible with the {@code java.util.Properties} class cannot have multiple occurrences of asingle property key, therefore a different storage scheme for multi-valued properties is needed. A possible storage scheme could look as follows:

 myProperty=value1,value2,value3

Here a comma is used as list delimiter. When parsing this property (and using a corresponding {@code ListDelimiterHandler} implementation) the string valueis split, and three values are added for the property key.

A {@code ListDelimiterHandler} knows how to parse and to escape propertyvalues. It is called by concrete {@code Configuration} implementations whenthey have to deal with properties with multiple values.

@version $Id: ListDelimiterHandler.java 1588831 2014-04-20 19:32:08Z oheger $ @since 2.0

     * @param value the value to be added
     */
    @Override
    protected void addPropertyInternal(String key, Object value)
    {
        ListDelimiterHandler oldHandler = getListDelimiterHandler();
        try
        {
            // temporarily disable delimiter parsing
            setListDelimiterHandler(DisabledListDelimiterHandler.INSTANCE);
            super.addPropertyInternal(key, value);

     * @return Properties created from the Configuration
     */
    public static Properties getProperties(Configuration config)
    {
        Properties props = new Properties();
        ListDelimiterHandler listHandler;
        boolean useDelimiterHandler;


        if(config instanceof AbstractConfiguration)
        {
            listHandler = ((AbstractConfiguration) config).getListDelimiterHandler();
            useDelimiterHandler = true;
        }
        else
        {
            listHandler = null;
            useDelimiterHandler = false;
        }


        for (Iterator<String> keys = config.getKeys(); keys.hasNext();)
        {
            String key = keys.next();
            List<Object> list = config.getList(key);


            String propValue;
            if (useDelimiterHandler)
            {
                try
                {
                    propValue =
                            String.valueOf(listHandler.escapeList(list,
                                    ListDelimiterHandler.NOOP_TRANSFORMER));
                }
                catch (Exception ex)
                {
                    // obviously, the list handler does not support splitting

Related Classes of org.apache.commons.configuration.convert.ListDelimiterHandler

All source code are property of their respective owners. Java is a trademark of Sun Microsystems, Inc and owned by ORACLE Inc. Contact coftware#gmail.com.