|
1 /** |
|
2 * SQL-DK |
|
3 * Copyright © 2013 František Kučera (frantovo.cz) |
|
4 * |
|
5 * This program is free software: you can redistribute it and/or modify |
|
6 * it under the terms of the GNU General Public License as published by |
|
7 * the Free Software Foundation, either version 3 of the License, or |
|
8 * (at your option) any later version. |
|
9 * |
|
10 * This program is distributed in the hope that it will be useful, |
|
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of |
|
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
|
13 * GNU General Public License for more details. |
|
14 * |
|
15 * You should have received a copy of the GNU General Public License |
|
16 * along with this program. If not, see <http://www.gnu.org/licenses/>. |
|
17 */ |
|
18 package info.globalcode.sql.dk.formatting; |
|
19 |
|
20 import info.globalcode.sql.dk.Parameter; |
|
21 import java.io.OutputStream; |
|
22 import java.util.EmptyStackException; |
|
23 import java.util.EnumSet; |
|
24 import java.util.List; |
|
25 import java.util.Stack; |
|
26 |
|
27 /** |
|
28 * |
|
29 * @author Ing. František Kučera (frantovo.cz) |
|
30 */ |
|
31 public abstract class AbstractFormatter implements Formatter { |
|
32 |
|
33 private Stack<State> state = new Stack<>(); |
|
34 private OutputStream outputStream; |
|
35 private ColumnsHeader currentColumnsHeader; |
|
36 private String currentQuery; |
|
37 private int currentColumnsCount; |
|
38 |
|
39 public AbstractFormatter(OutputStream outputStream) { |
|
40 this.outputStream = outputStream; |
|
41 state.push(State.ROOT); |
|
42 } |
|
43 |
|
44 /* |
|
45 * root |
|
46 * .database |
|
47 * ..resultSet |
|
48 * ...@query |
|
49 * ...@parameters |
|
50 * ...@columnsHeader |
|
51 * ...row |
|
52 * ....@columnValue |
|
53 * ..updatesResult |
|
54 * ...@query |
|
55 * ...@parameters |
|
56 * ...@updatedRowsCount |
|
57 * ...generatedKeys |
|
58 * ....resultSet (see above) |
|
59 */ |
|
60 protected enum State { |
|
61 |
|
62 ROOT, |
|
63 DATABASE, |
|
64 RESULT_SET, |
|
65 ROW, |
|
66 UPDATES_RESULT, |
|
67 GENERATED_KEYS |
|
68 } |
|
69 |
|
70 /** |
|
71 * Go down in hierarchy. |
|
72 * Pushes new state and verifies the old one. |
|
73 * |
|
74 * @param current the new state – currently entering |
|
75 * @param expected expected previous states (any of them is valid) |
|
76 * @return previous state |
|
77 * @throws IllegalStateException if previous state was not one from expected |
|
78 */ |
|
79 private State pushState(State current, EnumSet expected) { |
|
80 State previous = state.peek(); |
|
81 |
|
82 if (expected.contains(previous)) { |
|
83 state.push(current); |
|
84 return previous; |
|
85 } else { |
|
86 throw new IllegalStateException("Formatter was in wrong state: " + previous + " when it should be in one of: " + expected); |
|
87 } |
|
88 } |
|
89 |
|
90 protected State peekState(EnumSet expected) { |
|
91 State current = state.peek(); |
|
92 |
|
93 if (expected.contains(current)) { |
|
94 return current; |
|
95 } else { |
|
96 throw new IllegalStateException("Formatter is in wrong state: " + current + " when it should be in one of: " + expected); |
|
97 } |
|
98 |
|
99 } |
|
100 |
|
101 /** |
|
102 * Go up in hierarchy. |
|
103 * Pops the superior state/branch. |
|
104 * |
|
105 * @param expected expected superior state |
|
106 * @return the superior state |
|
107 * @throws IllegalStateException if superior state was not one from expected or if there is no |
|
108 * more superior state (we are at root level) |
|
109 */ |
|
110 private State popState(EnumSet expected) { |
|
111 try { |
|
112 State superior = state.pop(); |
|
113 if (expected.contains(superior)) { |
|
114 return superior; |
|
115 } else { |
|
116 throw new IllegalStateException("Formatter had wrong superior state: " + superior + " when it should be in one of: " + expected); |
|
117 } |
|
118 } catch (EmptyStackException e) { |
|
119 throw new IllegalStateException("Formatter was already at root level – there is nothing above that.", e); |
|
120 } |
|
121 } |
|
122 |
|
123 @Override |
|
124 public void writeStartDatabase() { |
|
125 pushState(State.DATABASE, EnumSet.of(State.ROOT)); |
|
126 } |
|
127 |
|
128 @Override |
|
129 public void writeEndDatabase() { |
|
130 popState(EnumSet.of(State.ROOT)); |
|
131 } |
|
132 |
|
133 @Override |
|
134 public void writeStartResultSet() { |
|
135 pushState(State.RESULT_SET, EnumSet.of(State.DATABASE, State.GENERATED_KEYS)); |
|
136 } |
|
137 |
|
138 @Override |
|
139 public void writeEndResultSet() { |
|
140 popState(EnumSet.of(State.DATABASE, State.GENERATED_KEYS)); |
|
141 currentColumnsHeader = null; |
|
142 } |
|
143 |
|
144 @Override |
|
145 public void writeQuery(String sql) { |
|
146 peekState(EnumSet.of(State.RESULT_SET, State.UPDATES_RESULT)); |
|
147 |
|
148 if (currentColumnsHeader == null) { |
|
149 currentQuery = sql; |
|
150 } else { |
|
151 throw new IllegalStateException("Query string '" + sql + "' must be set before columns header – was already set: " + currentColumnsHeader); |
|
152 } |
|
153 } |
|
154 |
|
155 @Override |
|
156 public void writeParameters(List<Parameter> parameters) { |
|
157 peekState(EnumSet.of(State.RESULT_SET, State.UPDATES_RESULT)); |
|
158 |
|
159 if (currentColumnsHeader != null) { |
|
160 throw new IllegalStateException("Parameters '" + parameters + "' must be set before columns header – was already set: " + currentColumnsHeader); |
|
161 } |
|
162 |
|
163 if (currentQuery == null) { |
|
164 throw new IllegalStateException("Parameters '" + parameters + "' must be set after query – was not yet set."); |
|
165 } |
|
166 } |
|
167 |
|
168 @Override |
|
169 public void writeColumnsHeader(ColumnsHeader header) { |
|
170 peekState(EnumSet.of(State.RESULT_SET, State.UPDATES_RESULT)); |
|
171 |
|
172 if (currentColumnsHeader == null) { |
|
173 currentColumnsHeader = header; |
|
174 } else { |
|
175 throw new IllegalStateException("Columns header can be set only once per result set – was already set: " + currentColumnsHeader); |
|
176 } |
|
177 } |
|
178 |
|
179 @Override |
|
180 public void writeStartRow() { |
|
181 pushState(State.ROW, EnumSet.of(State.RESULT_SET)); |
|
182 currentColumnsCount = 0; |
|
183 } |
|
184 |
|
185 @Override |
|
186 public void writeEndRow() { |
|
187 popState(EnumSet.of(State.RESULT_SET)); |
|
188 } |
|
189 |
|
190 @Override |
|
191 public void writeColumnValue(Object value) { |
|
192 peekState(EnumSet.of(State.ROW)); |
|
193 currentColumnsCount++; |
|
194 |
|
195 int declaredCount = currentColumnsHeader.getColumnCount(); |
|
196 if (currentColumnsCount > declaredCount) { |
|
197 throw new IllegalStateException("Current columns count is " + currentColumnsCount + " which is more than declared " + declaredCount + " in header."); |
|
198 } |
|
199 } |
|
200 |
|
201 @Override |
|
202 public void writeStartUpdatesResult() { |
|
203 pushState(State.RESULT_SET, EnumSet.of(State.DATABASE)); |
|
204 } |
|
205 |
|
206 @Override |
|
207 public void writeEndUpdatesResult() { |
|
208 popState(EnumSet.of(State.DATABASE)); |
|
209 currentColumnsHeader = null; |
|
210 } |
|
211 |
|
212 @Override |
|
213 public void writeUpdatedRowsCount(int updatedRowsCount) { |
|
214 peekState(EnumSet.of(State.UPDATES_RESULT)); |
|
215 } |
|
216 |
|
217 @Override |
|
218 public void writeStartGeneratedKeys() { |
|
219 pushState(State.GENERATED_KEYS, EnumSet.of(State.UPDATES_RESULT)); |
|
220 } |
|
221 |
|
222 @Override |
|
223 public void writeEndGeneratedKeys() { |
|
224 popState(EnumSet.of(State.UPDATES_RESULT)); |
|
225 } |
|
226 |
|
227 protected OutputStream getOutputStream() { |
|
228 return outputStream; |
|
229 } |
|
230 |
|
231 protected ColumnsHeader getCurrentColumnsHeader() { |
|
232 return currentColumnsHeader; |
|
233 } |
|
234 |
|
235 protected int getCurrentColumnsCount() { |
|
236 return currentColumnsCount; |
|
237 } |
|
238 /** |
|
239 * TODO: write SQLWarning |
|
240 */ |
|
241 } |