interpolator.addValueSource(new EnvarBasedValueSource());
            } catch (IOException e) {
                // ignored
            }
            interpolator.addValueSource(new MapBasedValueSource(System.getProperties()));

            try {
                if (fileString != null && !fileString.isEmpty()) {
                    fileString = interpolator.interpolate(fileString, "").replace("\\", "/");

import org.codehaus.plexus.interpolation.InterpolationException;

/**
 * Determines profile activation based on the existence/absence of some file.
 * File name interpolation support is limited to <code>${project.basedir}</code>
 * system properties and user properties.
 *
 * @see ActivationFile
 * @see org.apache.maven.internal.impl.model.DefaultModelValidator#validateRawModel
 */
@Named("file")
@Singleton