fix SearchCacheService

@@ -57,7 +57,7 @@ public class SearchCacheService {
 		sb.append("searchType:").append(searchParam.getSearchType() == null ? "" : searchParam.getSearchType().name()).append(';');
 		// 拼装报文
 		SearchSourceBuilder searchSourceBuilder = SearchParamUtils.genSearchSourceBuilderFromSearchParam(searchParam);
-		sb.append("searchSource:").append(searchSourceBuilder.toString()).append(';');
+		sb.append("searchSource:").append(searchSourceBuilder).append(';');
 		String cacheKey = "YOHOSEARCH:" + MD5Util.string2MD5(sb.toString());
 		return cacheKey;
 	}