| 1 | /* |
| 2 | |
| 3 | Derby - Class org.apache.derby.client.net.NetResultSet |
| 4 | |
| 5 | Copyright (c) 2001, 2005 The Apache Software Foundation or its licensors, where applicable. |
| 6 | |
| 7 | Licensed under the Apache License, Version 2.0 (the "License"); |
| 8 | you may not use this file except in compliance with the License. |
| 9 | You may obtain a copy of the License at |
| 10 | |
| 11 | http://www.apache.org/licenses/LICENSE-2.0 |
| 12 | |
| 13 | Unless required by applicable law or agreed to in writing, software |
| 14 | distributed under the License is distributed on an "AS IS" BASIS, |
| 15 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 16 | See the License for the specific language governing permissions and |
| 17 | limitations under the License. |
| 18 | |
| 19 | */ |
| 20 | package org.apache.derby.client.net; |
| 21 | |
| 22 | import org.apache.derby.client.am.Cursor; |
| 23 | import org.apache.derby.client.am.DisconnectException; |
| 24 | import org.apache.derby.client.am.Section; |
| 25 | import org.apache.derby.client.am.SqlException; |
| 26 | |
| 27 | |
| 28 | public class NetResultSet extends org.apache.derby.client.am.ResultSet { |
| 29 | // Alias for (NetConnection) super.statement.connection |
| 30 | private final NetConnection netConnection_; |
| 31 | |
| 32 | // Alias for (NetStatement) super.statement |
| 33 | private final NetStatement netStatement_; |
| 34 | |
| 35 | // Alias for (NetCursor) super.cursor |
| 36 | final NetCursor netCursor_; |
| 37 | |
| 38 | // Alias for (NetAgent) super.agent |
| 39 | final private NetAgent netAgent_; |
| 40 | |
| 41 | // Indicates whether the fixed row protocol is being used. If so, |
| 42 | // the fetch size will always be 1. |
| 43 | private boolean isFixedRowProtocol = false; |
| 44 | |
| 45 | //-----------------------------state------------------------------------------ |
| 46 | |
| 47 | // This is used to avoid sending multiple outovr over subsequent next()'s |
| 48 | public boolean firstOutovrBuilt_ = false; |
| 49 | |
| 50 | //---------------------constructors/finalizer--------------------------------- |
| 51 | |
| 52 | // parseOpnqrym() is called right after this constructor is called. |
| 53 | |
| 54 | NetResultSet(NetAgent netAgent, |
| 55 | NetStatement netStatement, |
| 56 | Cursor cursor, |
| 57 | int qryprctyp, //protocolType, CodePoint.FIXROWPRC | |
| 58 | // CodePoint.LMTBLKPRC |
| 59 | int sqlcsrhld, // holdOption, 0xF0 for false (default) | 0xF1 for true. |
| 60 | int qryattscr, // scrollOption, 0xF0 for false (default) | 0xF1 for true. |
| 61 | int qryattsns, // sensitivity, CodePoint.QRYUNK | |
| 62 | // CodePoint.QRYINS | |
| 63 | // CodePoint.QRYSNSSTC |
| 64 | int qryattset, // rowsetCursor, 0xF0 for false (default) | 0xF1 for true. |
| 65 | long qryinsid, // instanceIdentifier, 0 (if not returned, check default) or number |
| 66 | int actualResultSetType, |
| 67 | int actualResultSetConcurrency, |
| 68 | int actualResultSetHoldability) //throws DisconnectException |
| 69 | { |
| 70 | super(netAgent, |
| 71 | netStatement.statement_, |
| 72 | //new NetCursor (netAgent, qryprctyp), |
| 73 | cursor, |
| 74 | // call the constructor with the real resultSetType and resultSetConcurrency |
| 75 | // returned from the server |
| 76 | actualResultSetType, |
| 77 | actualResultSetConcurrency, |
| 78 | actualResultSetHoldability); |
| 79 | |
| 80 | netAgent_ = netAgent; |
| 81 | |
| 82 | // Set up cheat-links |
| 83 | netCursor_ = (NetCursor) cursor_; |
| 84 | netStatement_ = netStatement; |
| 85 | netConnection_ = netStatement.netConnection_; |
| 86 | |
| 87 | netCursor_.netResultSet_ = this; |
| 88 | |
| 89 | cursorHold_ = (sqlcsrhld != 0xf0); |
| 90 | if (qryattscr == 0xF1) { |
| 91 | scrollable_ = true; |
| 92 | } |
| 93 | |
| 94 | // The number of rows returned by the server will always be 1 when the |
| 95 | // Fixed Row Protocol is being used. |
| 96 | if (qryprctyp == CodePoint.FIXROWPRC) { |
| 97 | isFixedRowProtocol = true; |
| 98 | fetchSize_ = 1; |
| 99 | } else { |
| 100 | fetchSize_ = suggestedFetchSize_; |
| 101 | } |
| 102 | |
| 103 | switch (qryattsns) { |
| 104 | case CodePoint.QRYUNK: |
| 105 | sensitivity_ = sensitivity_unknown__; |
| 106 | break; |
| 107 | case CodePoint.QRYINS: |
| 108 | sensitivity_ = sensitivity_insensitive__; |
| 109 | break; |
| 110 | case CodePoint.QRYSNSSTC: |
| 111 | sensitivity_ = sensitivity_sensitive_static__; |
| 112 | break; |
| 113 | default: // shouldn't happen |
| 114 | break; |
| 115 | } |
| 116 | |
| 117 | if (qryattset == 0xF1) { |
| 118 | isRowsetCursor_ = true; |
| 119 | } |
| 120 | |
| 121 | queryInstanceIdentifier_ = qryinsid; |
| 122 | nestingLevel_ = (int) ((queryInstanceIdentifier_ >>> 48) & 0xFFFF); |
| 123 | } |
| 124 | |
| 125 | |
| 126 | //-------------------------------flow methods--------------------------------- |
| 127 | |
| 128 | // Go through the QRYDTA's received, and calculate the column offsets for each row. |
| 129 | protected void parseRowset_() throws SqlException { |
| 130 | int row = 0; |
| 131 | // Parse all the rows received in the rowset |
| 132 | // The index we are passing will keep track of which row in the rowset we are parsing |
| 133 | // so we can reuse the columnDataPosition/Length/IsNull arrays. |
| 134 | while (netCursor_.calculateColumnOffsetsForRow_(row, true)) { |
| 135 | rowsReceivedInCurrentRowset_++; |
| 136 | row++; |
| 137 | } |
| 138 | |
| 139 | // if rowset is not complete and an endqryrm was received, will skip the while loop |
| 140 | // and go to the checkAndThrow method. otherwise flow an cntqry to try to complete |
| 141 | // the rowset. |
| 142 | // -- there is no need to complete the rowset for rowset cursors. fetching stops when |
| 143 | // the end of data is returned or when an error occurs. all successfully fetched rows |
| 144 | // are returned to the user. the specific error is not returned until the next fetch. |
| 145 | while (rowsReceivedInCurrentRowset_ != fetchSize_ && |
| 146 | !netCursor_.allRowsReceivedFromServer() && !isRowsetCursor_ && |
| 147 | sensitivity_ != sensitivity_sensitive_dynamic__ && |
| 148 | sensitivity_ != sensitivity_sensitive_static__) { |
| 149 | flowFetchToCompleteRowset(); |
| 150 | while (netCursor_.calculateColumnOffsetsForRow_(row, true)) { |
| 151 | rowsReceivedInCurrentRowset_++; |
| 152 | row++; |
| 153 | } |
| 154 | } |
| 155 | checkAndThrowReceivedQueryTerminatingException(); |
| 156 | } |
| 157 | |
| 158 | public void setFetchSize_(int rows) { |
| 159 | // Do not change the fetchSize for Fixed Row Protocol |
| 160 | suggestedFetchSize_ = (rows == 0) ? 64 : rows; |
| 161 | if (!isFixedRowProtocol) { |
| 162 | fetchSize_ = suggestedFetchSize_; |
| 163 | } |
| 164 | } |
| 165 | |
| 166 | //-----------------------------helper methods--------------------------------- |
| 167 | |
| 168 | void flowFetchToCompleteRowset() throws DisconnectException { |
| 169 | try { |
| 170 | agent_.beginWriteChain(statement_); |
| 171 | |
| 172 | writeScrollableFetch_((generatedSection_ == null) ? statement_.section_ : generatedSection_, |
| 173 | fetchSize_ - rowsReceivedInCurrentRowset_, |
| 174 | scrollOrientation_relative__, |
| 175 | 1, |
| 176 | false); // false means do not disard pending |
| 177 | // partial row and pending query blocks |
| 178 | |
| 179 | agent_.flow(statement_); |
| 180 | readScrollableFetch_(); |
| 181 | agent_.endReadChain(); |
| 182 | } catch (SqlException e) { |
| 183 | throw new DisconnectException(agent_, e); |
| 184 | } |
| 185 | } |
| 186 | |
| 187 | void queryDataWasReturnedOnOpen() throws DisconnectException { |
| 188 | } |
| 189 | |
| 190 | // ------------------------------- abstract box car methods -------------------------------------- |
| 191 | public void writeFetch_(Section section) throws SqlException { |
| 192 | if (resultSetType_ == java.sql.ResultSet.TYPE_FORWARD_ONLY && fetchSize_ != 0 && |
| 193 | rowsYetToBeReceivedForRowset_ > 0) { |
| 194 | netAgent_.resultSetRequest_.writeFetch(this, |
| 195 | section, |
| 196 | rowsYetToBeReceivedForRowset_); |
| 197 | } else { |
| 198 | netAgent_.resultSetRequest_.writeFetch(this, |
| 199 | section, |
| 200 | fetchSize_); |
| 201 | } |
| 202 | } |
| 203 | |
| 204 | public void readFetch_() throws SqlException { |
| 205 | netAgent_.resultSetReply_.readFetch(this); |
| 206 | } |
| 207 | |
| 208 | public void writeScrollableFetch_(Section section, |
| 209 | int fetchSize, |
| 210 | int orientation, |
| 211 | long rowToFetch, |
| 212 | boolean resetQueryBlocks) throws SqlException { |
| 213 | netAgent_.resultSetRequest_.writeScrollableFetch(this, |
| 214 | section, |
| 215 | fetchSize, |
| 216 | orientation, |
| 217 | rowToFetch, |
| 218 | resetQueryBlocks); |
| 219 | } |
| 220 | |
| 221 | // think about splitting out the position cursor stuff from the fetch stuff |
| 222 | // use commented out abstract position cursor methods above |
| 223 | public void readScrollableFetch_() throws SqlException { |
| 224 | netAgent_.resultSetReply_.readScrollableFetch(this); |
| 225 | } |
| 226 | |
| 227 | public void writePositioningFetch_(Section section, |
| 228 | int orientation, |
| 229 | long rowToFetch) throws SqlException { |
| 230 | netAgent_.resultSetRequest_.writePositioningFetch(this, |
| 231 | section, |
| 232 | orientation, |
| 233 | rowToFetch); |
| 234 | } |
| 235 | |
| 236 | public void readPositioningFetch_() throws SqlException { |
| 237 | netAgent_.resultSetReply_.readPositioningFetch(this); |
| 238 | } |
| 239 | |
| 240 | public void writeCursorClose_(Section section) throws SqlException { |
| 241 | netAgent_.resultSetRequest_.writeCursorClose(this, section); |
| 242 | } |
| 243 | |
| 244 | public void readCursorClose_() throws SqlException { |
| 245 | netAgent_.resultSetReply_.readCursorClose(this); |
| 246 | } |
| 247 | |
| 248 | /** |
| 249 | * Method that is invoked by <code>closeX()</code> before the |
| 250 | * result set is actually being closed. If QRYCLSIMP is enabled on |
| 251 | * the cursor, scan data buffer for end of data (SQL state |
| 252 | * 02000). If end of data is received, the result set is closed on |
| 253 | * the server. |
| 254 | * |
| 255 | * @exception SqlException |
| 256 | */ |
| 257 | protected void preClose_() throws SqlException { |
| 258 | if (netCursor_.getQryclsimpEnabled()) { |
| 259 | netCursor_.scanDataBufferForEndOfData(); |
| 260 | } |
| 261 | } |
| 262 | } |