Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
QueryResults |
|
| 1.0;1 |
1 | /** | |
2 | * Copyright 2005-2011 The Kuali Foundation | |
3 | * | |
4 | * Licensed under the Educational Community License, Version 2.0 (the "License"); | |
5 | * you may not use this file except in compliance with the License. | |
6 | * You may obtain a copy of the License at | |
7 | * | |
8 | * http://www.opensource.org/licenses/ecl2.php | |
9 | * | |
10 | * Unless required by applicable law or agreed to in writing, software | |
11 | * distributed under the License is distributed on an "AS IS" BASIS, | |
12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
13 | * See the License for the specific language governing permissions and | |
14 | * limitations under the License. | |
15 | */ | |
16 | package org.kuali.rice.core.api.criteria; | |
17 | ||
18 | ||
19 | import java.util.List; | |
20 | ||
21 | /** | |
22 | * Contains a collection of results from a query. This interface exists as a | |
23 | * utility for services that want to implement it to represents results from | |
24 | * criteria-based (or other) queries. | |
25 | * | |
26 | * <p> | |
27 | * Also may provide information related to the count of rows returned | |
28 | * by the query as well as whether or not the query returned all available results. | |
29 | * </p> | |
30 | * | |
31 | * <p> | |
32 | * All the information in this interface is populated depending on the information | |
33 | * requested via the {@link QueryByCriteria}. | |
34 | * </p> | |
35 | * | |
36 | * @param <T> the type of the objects contained within the results list | |
37 | * | |
38 | * @author Kuali Rice Team (rice.collab@kuali.org) | |
39 | * | |
40 | */ | |
41 | public interface QueryResults<T> { | |
42 | ||
43 | /** | |
44 | * Return the list of results that are contained within. This list can | |
45 | * be empty but it should never be null. | |
46 | * | |
47 | * @return the list of results | |
48 | */ | |
49 | List<T> getResults(); | |
50 | ||
51 | /** | |
52 | * Gets the total number of records that match the executed query. Note | |
53 | * that this number will not necessarily match the number of results | |
54 | * returned by {@link #getResults()} as the query may cut off the number | |
55 | * of records returned by the actual query request. In these cases, the | |
56 | * total row count represents the total number of results which would be | |
57 | * returned by the query if there was no cap on the results returned (i.e. | |
58 | * the equivalent of the result of a "count" query in SQL). | |
59 | * | |
60 | * <p> | |
61 | * The total row count is optional depending on whether or not the | |
62 | * client requested the total row count when invoking the query. The client | |
63 | * requests this information by setting the {@link CountFlag#INCLUDE} or | |
64 | * {@link CountFlag#ONLY} on the {@link QueryByCriteria}. It's also | |
65 | * possible that the query is unable to produce a total row count depending | |
66 | * on the back-end implementation, in which cases this value will also not | |
67 | * be available. | |
68 | * </p> | |
69 | * | |
70 | * <p> | |
71 | * Will never be less than 0. | |
72 | * <p> | |
73 | * | |
74 | * @return the total number of rows, or null if the total row count was not | |
75 | * requested by the query or could not be determined | |
76 | */ | |
77 | Integer getTotalRowCount(); | |
78 | ||
79 | /** | |
80 | * Indicates if there are more results available for the query immediately | |
81 | * following the last result that was returned. In this case, the records | |
82 | * returned in {@link #getResults()} will not include the complete result | |
83 | * set for the query. This could be because the query only requested a | |
84 | * certain number of rows, or that the query couldn't return the number | |
85 | * of rows that were requested. | |
86 | * | |
87 | * <p> | |
88 | * It is intended that this value be used to facilitate paging or | |
89 | * reporting in the client in cases where that is desired. | |
90 | * </p> | |
91 | * | |
92 | * <p> | |
93 | * This information will only be available if the client sets a limit on the | |
94 | * results returned. This limit is set with the maxResults field on the | |
95 | * {@link QueryByCriteria}. | |
96 | * </p> | |
97 | * | |
98 | * @return true if there are more results available for the query, false otherwise | |
99 | */ | |
100 | boolean isMoreResultsAvailable(); | |
101 | } |