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package org.apache.commons.configuration2.convert;


Definition of an interface used by ListDelimiterHandler to perform additional transformations on behalf of a configuration when a property value is escaped.

Some Configuration implementations require a special encoding of their property values before they get written on disk. In some constellations, e.g. when a property with multiple values is to be forced on a single line, this encoding has to be done together with the escaping of list delimiter characters - which is in the responsibility of ListDelimiterHandler.

In order to allow a proper collaboration between the parties involved, this interface was introduced. A configuration object provides an implementation of ValueTransformer and passes it to the ListDelimiterHandler when escaping of properties is needed. The delimiter handler can then call back to perform the additional encoding as its pleasure.

Since:2.0
/** * <p> * Definition of an interface used by {@link ListDelimiterHandler} to perform * additional transformations on behalf of a configuration when a property value * is escaped. * </p> * <p> * Some {@code Configuration} implementations require a special encoding of * their property values before they get written on disk. In some * constellations, e.g. when a property with multiple values is to be forced on * a single line, this encoding has to be done together with the escaping of * list delimiter characters - which is in the responsibility of * {@link ListDelimiterHandler}. * </p> * <p> * In order to allow a proper collaboration between the parties involved, this * interface was introduced. A configuration object provides an implementation * of {@code ValueTransformer} and passes it to the {@code ListDelimiterHandler} * when escaping of properties is needed. The delimiter handler can then call * back to perform the additional encoding as its pleasure. * </p> * * @since 2.0 */
public interface ValueTransformer {
Performs an arbitrary encoding of the passed in value object. This method is called by a ListDelimiterHandler implementation before or after list delimiters have been escaped.
Params:
  • value – the property value to be transformed
Returns:the transformed property value
/** * Performs an arbitrary encoding of the passed in value object. This method * is called by a {@link ListDelimiterHandler} implementation before or * after list delimiters have been escaped. * * @param value the property value to be transformed * @return the transformed property value */
Object transformValue(Object value); }