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1
5 package org.h2.result;
6
7 import java.io.IOException  ;
8 import java.sql.SQLException ;
9
10 import org.h2.engine.Constants;
11 import org.h2.engine.SessionRemote;
12 import org.h2.message.Message;
13 import org.h2.util.ObjectArray;
14 import org.h2.value.Transfer;
15 import org.h2.value.Value;
16
17 public class ResultRemote implements ResultInterface {
18
19 private SessionRemote session;
20 private Transfer transfer;
21 private int id;
22 private ResultColumn[] columns;
23 private Value[] currentRow;
24 private int rowId, rowCount;
25 private ObjectArray result;
26
27 private boolean isUpdateCount;
28 private int updateCount;
29
30 public ResultRemote(int updateCount) {
31 this.isUpdateCount = true;
32 this.updateCount = updateCount;
33 }
34
35 public boolean isUpdateCount() {
36 return isUpdateCount;
37 }
38
39 public int getUpdateCount() {
40 return updateCount;
41 }
42
43 public ResultRemote(SessionRemote session, Transfer transfer, int id, int columnCount, int readRows) throws IOException , SQLException {
44 this.session = session;
45 this.transfer = transfer;
46 this.id = id;
47 this.columns = new ResultColumn[columnCount];
48 rowCount = transfer.readInt();
49 for (int i = 0; i < columnCount; i++) {
50 columns[i] = new ResultColumn(transfer);
51 }
52 rowId = -1;
53 if(rowCount < readRows) {
54 result = new ObjectArray();
55 readFully();
56 sendClose();
57 }
58 }
59
60 private void readFully() throws SQLException {
61 while(true) {
62 Value[] values = fetchRow(false);
63 if(values == null) {
64 break;
65 }
66 result.add(values);
67 }
68 }
69
70 public String getAlias(int i) {
71 return columns[i].alias;
72 }
73
74 public String getSchemaName(int i) {
75 return columns[i].schemaName;
76 }
77
78 public String getTableName(int i) {
79 return columns[i].tableName;
80 }
81
82 public String getColumnName(int i) {
83 return columns[i].columnName;
84 }
85
86 public int getColumnType(int i) {
87 return columns[i].columnType;
88 }
89
90 public long getColumnPrecision(int i) {
91 return columns[i].precision;
92 }
93
94 public int getColumnScale(int i) {
95 return columns[i].scale;
96 }
97
98 public int getDisplaySize(int i) {
99 return columns[i].displaySize;
100 }
101
102 public boolean isAutoIncrement(int i) {
103 return columns[i].autoIncrement;
104 }
105
106 public int getNullable(int i) {
107 return columns[i].nullable;
108 }
109
110 public void reset() throws SQLException {
111 rowId = -1;
112 currentRow = null;
113 if(session == null) {
114 return;
115 }
116 synchronized (session) {
117 session.checkClosed();
118 try {
119 session.traceOperation("RESULT_RESET", id);
120 transfer.writeInt(SessionRemote.RESULT_RESET).writeInt(id).flush();
121 } catch (IOException e) {
122 throw Message.convert(e);
123 }
124 }
125 }
126
127 public Value[] currentRow() {
128 return currentRow;
129 }
130
131 public boolean next() throws SQLException {
132 if (rowId < rowCount) {
134 rowId++;
135 if (rowId < rowCount) {
136 if(session == null) {
137 currentRow = (Value[]) result.get(rowId);
138 } else {
139 currentRow = fetchRow(true);
140 }
141 return true;
142 }
143 currentRow = null;
144 }
145 return false;
146 }
147
148 public int getRowId() {
149 return rowId;
150 }
151
152 public int getVisibleColumnCount() {
153 return columns.length;
154 }
155
156 public int getRowCount() {
157 return rowCount;
158 }
159
160 private void sendClose() {
161 if (session == null) {
162 return;
163 }
164 synchronized (session) {
166 try {
167 session.traceOperation("RESULT_CLOSE", id);
168 transfer.writeInt(SessionRemote.RESULT_CLOSE).writeInt(id);
169 } catch (IOException e) {
170 session.getTrace().error("close", e);
171 } finally {
172 transfer = null;
173 session = null;
174 }
175 }
176 }
177
178 public void close() {
179 result = null;
180 sendClose();
181 }
182
183
190 private Value[] fetchRow(boolean sendFetch) throws SQLException {
191 synchronized (session) {
192 session.checkClosed();
193 try {
194 if(id <= session.getCurrentId() - Constants.SERVER_CACHED_OBJECTS / 2) {
195 int newId = session.getNextId();
197 session.traceOperation("CHANGE_ID", id);
198 transfer.writeInt(SessionRemote.CHANGE_ID).writeInt(id).writeInt(newId);
199 id = newId;
200 }
202 if(sendFetch) {
203 session.traceOperation("RESULT_FETCH_ROW", id);
204 transfer.writeInt(SessionRemote.RESULT_FETCH_ROW).writeInt(id);
205 session.done(transfer);
206 }
207 boolean row = transfer.readBoolean();
208 if (row) {
209 int len = columns.length;
210 Value[] values = new Value[len];
211 for (int i = 0; i < len; i++) {
212 values[i] = transfer.readValue();
213 }
214 return values;
215 } else {
216 sendClose();
217 return null;
218 }
219 } catch (IOException e) {
220 throw Message.convert(e);
221 }
222 }
223 }
224
225 }
226 |
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