BooleanTransformer.java

package silentium.commons.configuration.transformers;

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

import java.lang.reflect.Field;

/**
 * This class implements basic boolean transfromer.
 * <p/>
 * Boolean can be represented by "true/false" (case doen't matter) or "1/0". In other cases
 * {@link org.bnsworld.commons.configuration.TransformationException} is thrown
 *
 * @author SoulKeeper
 */
public class BooleanTransformer implements PropertyTransformer<Boolean> {
	/**
	 * Shared instance of this transformer, it's thread safe so no need to create multiple instances
	 */
	public static final BooleanTransformer SHARED_INSTANCE = new BooleanTransformer();

	/**
	 * Transforms string to boolean.
	 *
	 * @param value value that will be transformed
	 * @param field value will be assigned to this field
	 * @return Boolean object that represents transformed value
	 * @throws TransformationException if something goes wrong
	 */
	@Override
	public Boolean transform(final String value, final Field field) throws TransformationException {
		// We should have error here if value is not correct, default
		// "Boolean.parseBoolean" returns false if string
		// is not "true" ignoring case
		if ("true".equalsIgnoreCase(value) || "1".equals(value))
			return true;
		else if ("false".equalsIgnoreCase(value) || "0".equals(value))
			return false;
		else
			throw new TransformationException("Invalid boolean string: " + value);
	}
}