PatternTransformer.java

package silentium.commons.configuration.transformers;

import silentium.commons.configuration.PropertyTransformer;
import silentium.commons.configuration.TransformationException;

import java.lang.reflect.Field;
import java.util.regex.Pattern;

/**
 * Authomatic pattern transformer for RegExp resolving
 *
 * @author SoulKeeper
 */
@SuppressWarnings("unchecked")
public class PatternTransformer implements PropertyTransformer {
	/**
	 * Shared instance of this transformer
	 */
	public static final PatternTransformer SHARED_INSTANCE = new PatternTransformer();

	/**
	 * Transforms String to Pattern object
	 *
	 * @param value value that will be transformed
	 * @param field value will be assigned to this field
	 * @return Pattern Object
	 * @throws TransformationException if pattern is not valid
	 */
	@Override
	public Pattern transform(final String value, final Field field) throws TransformationException {
		try {
			return Pattern.compile(value);
		} catch (Exception e) {
			throw new TransformationException("Not valid RegExp: " + value, e);
		}
	}
}