Throw 404 instead of 500 if no leaderboard entry could be found.

This happens regularly if the leaderboard record is inactive.
Fixes #371, also fixes #302

src/main/java/com/faforever/api/leaderboard/LeaderboardController.java

@@ -1,6 +1,8 @@
 package com.faforever.api.leaderboard;
 
-import com.faforever.api.web.ResourceNotFoundException;
+import com.faforever.api.error.Error;
+import com.faforever.api.error.ErrorCode;
+import com.faforever.api.error.NotFoundApiException;
 import com.google.common.collect.ImmutableMap;
 import com.yahoo.elide.jsonapi.models.Data;
 import com.yahoo.elide.jsonapi.models.JsonApiDocument;
@@ -76,13 +78,13 @@ public CompletableFuture<JsonApiDocument> getGlobal(@RequestParam(value = "page[
   @Async
   @RequestMapping(path = "/ladder1v1/{playerId}", method = RequestMethod.GET)
   @ApiOperation("Lists the ladder1v1 leaderboard for the specified player")
-  public CompletableFuture<JsonApiDocument> getSingleLadder1v1(@PathVariable("playerId") String playerId) {
-    Ladder1v1LeaderboardEntry entry = leaderboardService.getLadder1v1Entry(Integer.valueOf(playerId));
+  public CompletableFuture<JsonApiDocument> getSingleLadder1v1(@PathVariable("playerId") Integer playerId) {
+    Ladder1v1LeaderboardEntry entry = leaderboardService.getLadder1v1Entry(playerId);
     if (entry == null) {
-      throw new ResourceNotFoundException("No ladder1v1 entry found for player: " + playerId);
+      throw new NotFoundApiException(new Error(ErrorCode.ENTITY_NOT_FOUND, playerId));
     }
 
-    Resource resource = new Resource(LADDER_1V1_LEADERBOARD_ENTRY, playerId, ImmutableMap.<String, Object>builder()
+    Resource resource = new Resource(LADDER_1V1_LEADERBOARD_ENTRY, playerId.toString(), ImmutableMap.<String, Object>builder()
       .put("name", entry.getPlayerName())
       .put("mean", entry.getMean())
       .put("deviation", entry.getDeviation())
@@ -99,13 +101,13 @@ public CompletableFuture<JsonApiDocument> getSingleLadder1v1(@PathVariable("play
   @Async
   @RequestMapping(path = "/global/{playerId}", method = RequestMethod.GET)
   @ApiOperation("Lists the global leaderboard for the specified player")
-  public CompletableFuture<JsonApiDocument> getSingleGlobal(@PathVariable("playerId") String playerId) {
-    GlobalLeaderboardEntry entry = leaderboardService.getGlobalEntry(Integer.valueOf(playerId));
+  public CompletableFuture<JsonApiDocument> getSingleGlobal(@PathVariable("playerId") Integer playerId) {
+    GlobalLeaderboardEntry entry = leaderboardService.getGlobalEntry(playerId);
     if (entry == null) {
-      throw new ResourceNotFoundException("No global leaderboard entry found for player: " + playerId);
+      throw new NotFoundApiException(new Error(ErrorCode.ENTITY_NOT_FOUND, playerId));
     }
 
-    Resource resource = new Resource(GLOBAL_LEADERBOARD_ENTRY, playerId, ImmutableMap.<String, Object>builder()
+    Resource resource = new Resource(GLOBAL_LEADERBOARD_ENTRY, playerId.toString(), ImmutableMap.<String, Object>builder()
       .put("name", entry.getPlayerName())
       .put("mean", entry.getMean())
       .put("deviation", entry.getDeviation())