| package org.onlab.onos.store.service; |
| |
| /** |
| * A container object which either has a result or an exception. |
| * <p> |
| * If a result is present, get() will return it otherwise get() will throw |
| * the exception that was encountered in the process of generating the result. |
| * </p> |
| * @param <R> type of result. |
| * @param <E> exception encountered in generating the result. |
| */ |
| public interface OptionalResult<R, E extends Throwable> { |
| |
| /** |
| * Returns the result or throws an exception if there is no |
| * valid result. |
| * @return result |
| */ |
| public R get(); |
| |
| /** |
| * Returns true if there is a valid result. |
| * @return true is yes, false otherwise. |
| */ |
| public boolean hasValidResult(); |
| } |