1 /* |
|
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. |
|
3 * |
|
4 * Copyright 2018 Mike Becker. All rights reserved. |
|
5 * |
|
6 * Redistribution and use in source and binary forms, with or without |
|
7 * modification, are permitted provided that the following conditions are met: |
|
8 * |
|
9 * 1. Redistributions of source code must retain the above copyright |
|
10 * notice, this list of conditions and the following disclaimer. |
|
11 * |
|
12 * 2. Redistributions in binary form must reproduce the above copyright |
|
13 * notice, this list of conditions and the following disclaimer in the |
|
14 * documentation and/or other materials provided with the distribution. |
|
15 * |
|
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
|
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
|
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
|
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
|
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
|
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
|
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
|
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
|
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
|
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
|
26 * POSSIBILITY OF SUCH DAMAGE. |
|
27 * |
|
28 */ |
|
29 package de.uapcore.lightpit.dao; |
|
30 |
|
31 import java.sql.*; |
|
32 import java.util.ArrayList; |
|
33 import java.util.List; |
|
34 import java.util.Optional; |
|
35 import java.util.function.Function; |
|
36 |
|
37 /** |
|
38 * Some DAO utilities. |
|
39 */ |
|
40 public final class Functions { |
|
41 |
|
42 public static String getSafeString(ResultSet rs, String column) throws SQLException { |
|
43 return Optional.ofNullable(rs.getString(column)).orElse(""); |
|
44 } |
|
45 |
|
46 public static void setStringOrNull(PreparedStatement stmt, int index, String str) throws SQLException { |
|
47 if (str == null || str.isBlank()) { |
|
48 stmt.setNull(index, Types.VARCHAR); |
|
49 } else { |
|
50 stmt.setString(index, str); |
|
51 } |
|
52 } |
|
53 |
|
54 public static void setDateOrNull(PreparedStatement stmt, int index, Date date) throws SQLException { |
|
55 if (date == null) { |
|
56 stmt.setNull(index, Types.DATE); |
|
57 } else { |
|
58 stmt.setDate(index, date); |
|
59 } |
|
60 } |
|
61 |
|
62 public static <T> void setForeignKeyOrNull(PreparedStatement stmt, int index, T instance, Function<? super T, Integer> keyGetter) throws SQLException { |
|
63 Integer key = Optional.ofNullable(instance).map(keyGetter).orElse(null); |
|
64 if (key == null) { |
|
65 stmt.setNull(index, Types.INTEGER); |
|
66 } else { |
|
67 stmt.setInt(index, key); |
|
68 } |
|
69 } |
|
70 |
|
71 @FunctionalInterface |
|
72 public interface ResultSetMapper<T> { |
|
73 T apply(ResultSet rs) throws SQLException; |
|
74 } |
|
75 |
|
76 public static <T> List<T> list(PreparedStatement stmt, ResultSetMapper<T> mapper) throws SQLException { |
|
77 List<T> results = new ArrayList<>(); |
|
78 try (var result = stmt.executeQuery()) { |
|
79 while (result.next()) { |
|
80 final var project = mapper.apply(result); |
|
81 results.add(project); |
|
82 } |
|
83 } |
|
84 return results; |
|
85 } |
|
86 |
|
87 public static <T> T find(PreparedStatement stmt, ResultSetMapper<T> mapper) throws SQLException { |
|
88 try (var result = stmt.executeQuery()) { |
|
89 if (result.next()) { |
|
90 final var ent = mapper.apply(result); |
|
91 return ent; |
|
92 } else { |
|
93 return null; |
|
94 } |
|
95 } |
|
96 } |
|
97 |
|
98 private Functions() { |
|
99 |
|
100 } |
|
101 } |
|