java/jdbc-loopback-driver/src/info/globalcode/jdbc/loopback/PreparedStatement.java
author František Kučera <franta-hg@frantovo.cz>
Tue, 26 Feb 2019 18:19:49 +0100
branchv_0
changeset 236 a3ec71fa8e17
parent 176 9aa00e214020
permissions -rw-r--r--
Avoid reusing/rewriting the DB connection properties.
There was weird random errors while testing connection to multiple DB in parallel when one of them was meta connection to same DB connection.
Two kinds of exception: 1) missing password 2) „Passing DB password as CLI parameter is insecure!“
     1 /**
     2  * SQL-DK
     3  * Copyright © 2014 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.jdbc.loopback;
    19 
    20 import java.sql.SQLException;
    21 import java.sql.SQLWarning;
    22 import java.sql.Types;
    23 import java.util.ArrayList;
    24 import java.util.HashMap;
    25 import java.util.List;
    26 import java.util.Map;
    27 
    28 /**
    29  *
    30  * @author Ing. František Kučera (frantovo.cz)
    31  */
    32 public class PreparedStatement extends AbstractPreparedStatement {
    33 
    34 	private final Map<Integer, ObjectParameter> parameters = new HashMap<>();
    35 	private List<Object[]> table;
    36 	private final ResultSetMetaData metadata = new ResultSetMetaData();
    37 
    38 	@Override
    39 	public void setObject(int parameterNumber, Object data, int targetSqlType) throws SQLException {
    40 		parameters.put(parameterNumber, new ObjectParameter(data, targetSqlType));
    41 	}
    42 
    43 	@Override
    44 	public boolean execute() throws SQLException {
    45 
    46 		if (parameters.size() < 1) {
    47 			throw new SQLException("Missing first parameter (column count)");
    48 		} else {
    49 			int columnCount = Integer.valueOf(String.valueOf(parameters.get(1).getData()));
    50 
    51 			for (int i = 0; i < columnCount; i++) {
    52 				String label = parameters.get(1 + i + 1).getData().toString();
    53 				metadata.addColumn(new ResultSetMetaData.ColumnDescriptor(Types.VARCHAR, "VARCHAR", label, label));
    54 			}
    55 
    56 			int cellIndex = 0;
    57 
    58 			table = new ArrayList<>();
    59 			Object[] currentRow = null;
    60 
    61 			for (int parameterNumber = (1 + columnCount + 1); true; parameterNumber++) {
    62 				ObjectParameter data = parameters.get(parameterNumber);
    63 				if (data == null) {
    64 					break;
    65 				} else {
    66 					int columnIndex = cellIndex % columnCount;
    67 					cellIndex++;
    68 					if (columnIndex == 0) {
    69 						currentRow = new Object[columnCount];
    70 						table.add(currentRow);
    71 					}
    72 					currentRow[columnIndex] = data.getData();
    73 				}
    74 			}
    75 
    76 			return true;
    77 		}
    78 	}
    79 
    80 	@Override
    81 	public java.sql.ResultSet getResultSet() throws SQLException {
    82 		return new ResultSet(metadata, table);
    83 	}
    84 
    85 	@Override
    86 	public int getUpdateCount() throws SQLException {
    87 		return -1;
    88 	}
    89 
    90 	@Override
    91 	public boolean getMoreResults() throws SQLException {
    92 		return false;
    93 	}
    94 
    95 	@Override
    96 	public void close() throws SQLException {
    97 	}
    98 
    99 	@Override
   100 	public SQLWarning getWarnings() throws SQLException {
   101 		return null;
   102 	}
   103 
   104 	@Override
   105 	public void clearWarnings() throws SQLException {
   106 	}
   107 }