Ray Milkey | fbfd2da | 2014-05-09 17:30:14 -0700 | [diff] [blame^] | 1 | package net.onrc.onos.api.rest; |
| 2 | |
| 3 | import java.util.HashMap; |
| 4 | import java.util.Map; |
| 5 | |
| 6 | /** |
| 7 | * Maintains a catalog of RestErrors and allows lookup by error code. |
| 8 | */ |
| 9 | public final class RestErrorCatalog { |
| 10 | |
| 11 | /** |
| 12 | * Hide the default constructor of a utility class. |
| 13 | */ |
| 14 | private RestErrorCatalog() { } |
| 15 | |
| 16 | /** |
| 17 | * Static list of known errors. Someday this will be read in from an |
| 18 | * external file. |
| 19 | */ |
| 20 | private static final RestError[] ERROR_LIST = { |
| 21 | new RestError(RestErrorCodes.RestErrorCode.INTENT_NOT_FOUND, |
| 22 | "Intent not found", |
| 23 | "An intent with the identifier {} was not found."), |
| 24 | new RestError(RestErrorCodes.RestErrorCode.INTENT_ALREADY_EXISTS, |
| 25 | "Intent already exists", |
| 26 | "An intent with the identifier {} could not be created " + |
| 27 | "because one already exists."), |
| 28 | new RestError(RestErrorCodes.RestErrorCode.INTENT_NO_PATH, |
| 29 | "No path found", |
| 30 | "No path found between {} and {}"), |
| 31 | |
| 32 | }; |
| 33 | |
| 34 | /** |
| 35 | * Singleton implementation using the demand holder idiom. |
| 36 | */ |
| 37 | private static class RestErrorMapHolder { |
| 38 | /** |
| 39 | * Load up the error map. |
| 40 | * |
| 41 | * @return REST error map |
| 42 | */ |
| 43 | private static Map<Integer, RestError> initializeRestErrorMap() { |
| 44 | restErrorMap = new HashMap<>(); |
| 45 | for (final RestError restError : ERROR_LIST) { |
| 46 | restErrorMap.put(restError.getCode().ordinal(), restError); |
| 47 | } |
| 48 | return restErrorMap; |
| 49 | } |
| 50 | |
| 51 | /** |
| 52 | * Fetch the singleton map. |
| 53 | * |
| 54 | * @return map of the Rest Errors that was created from the known error |
| 55 | * list. |
| 56 | */ |
| 57 | public static Map<Integer, RestError> getRestErrorMap() { |
| 58 | return restErrorMap; |
| 59 | } |
| 60 | |
| 61 | |
| 62 | private static Map<Integer, RestError> restErrorMap = initializeRestErrorMap(); |
| 63 | } |
| 64 | |
| 65 | /** |
| 66 | * Fetch the map of REST errors. |
| 67 | * |
| 68 | * @return map of possible REST errors. |
| 69 | */ |
| 70 | public static Map<Integer, RestError> getRestErrorMap() { |
| 71 | return RestErrorMapHolder.getRestErrorMap(); |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * Fetch the RestError for the given code. |
| 76 | * |
| 77 | * @param code the code for the message to look up. |
| 78 | * @return the REST error for the code if one exists, null if it does not |
| 79 | * exist. |
| 80 | */ |
| 81 | public static RestError getRestError(final RestErrorCodes.RestErrorCode code) { |
| 82 | return getRestErrorMap().get(code.ordinal()); |
| 83 | } |
| 84 | } |