| 1 | /* ============================================================= |
| 2 | * SmallSQL : a free Java DBMS library for the Java(tm) platform |
| 3 | * ============================================================= |
| 4 | * |
| 5 | * (C) Copyright 2004-2006, by Volker Berlin. |
| 6 | * |
| 7 | * Project Info: http://www.smallsql.de/ |
| 8 | * |
| 9 | * This library is free software; you can redistribute it and/or modify it |
| 10 | * under the terms of the GNU Lesser General Public License as published by |
| 11 | * the Free Software Foundation; either version 2.1 of the License, or |
| 12 | * (at your option) any later version. |
| 13 | * |
| 14 | * This library is distributed in the hope that it will be useful, but |
| 15 | * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| 16 | * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
| 17 | * License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU Lesser General Public |
| 20 | * License along with this library; if not, write to the Free Software |
| 21 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, |
| 22 | * USA. |
| 23 | * |
| 24 | * [Java is a trademark or registered trademark of Sun Microsystems, Inc. |
| 25 | * in the United States and other countries.] |
| 26 | * |
| 27 | * --------------- |
| 28 | * Command.java |
| 29 | * --------------- |
| 30 | * Author: Volker Berlin |
| 31 | * |
| 32 | */ |
| 33 | package smallsql.database; |
| 34 | |
| 35 | import java.sql.*; |
| 36 | |
| 37 | |
| 38 | abstract class Command { |
| 39 | |
| 40 | int type; |
| 41 | String catalog; |
| 42 | String name; |
| 43 | |
| 44 | SSResultSet rs; |
| 45 | int updateCount = -1; |
| 46 | |
| 47 | /** List of Columns */ |
| 48 | final Expressions columnExpressions; |
| 49 | |
| 50 | /** List of ExpressionValue */ |
| 51 | Expressions params = new Expressions(); |
| 52 | |
| 53 | final Logger log; |
| 54 | |
| 55 | Command(Logger log){ |
| 56 | this.log = log; |
| 57 | this.columnExpressions = new Expressions(); |
| 58 | } |
| 59 | |
| 60 | Command(Logger log, Expressions columnExpressions){ |
| 61 | this.log = log; |
| 62 | this.columnExpressions = columnExpressions; |
| 63 | } |
| 64 | |
| 65 | |
| 66 | /** |
| 67 | * Add a Expression that returns the value for Column. This method is used |
| 68 | * from SQLParser for different Commands (CommandSelect, CommandInsert). |
| 69 | * @see SQLParser#select() |
| 70 | * @see SQLParser#insert() |
| 71 | */ |
| 72 | void addColumnExpression( Expression column ){ |
| 73 | columnExpressions.add( column ); |
| 74 | } |
| 75 | |
| 76 | void addParameter( ExpressionValue param ){ |
| 77 | params.add( param ); |
| 78 | } |
| 79 | |
| 80 | |
| 81 | /** |
| 82 | * check if all parameters are set |
| 83 | */ |
| 84 | void verifyParams() throws SQLException{ |
| 85 | for(int p=0; p<params.size(); p++){ |
| 86 | if(((ExpressionValue)params.get(p)).isEmpty()) |
| 87 | throw Utils.createSQLException("Parameter " + (p+1) + " is empty."); |
| 88 | } |
| 89 | } |
| 90 | |
| 91 | /** |
| 92 | * Clear all parameters of a PreparedStatement |
| 93 | */ |
| 94 | void clearParams(){ |
| 95 | for(int p=0; p<params.size(); p++){ |
| 96 | ((ExpressionValue)params.get(p)).clear(); |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | /** |
| 101 | * Get a PreparedStatement parameter. |
| 102 | * The idx starts with 1. |
| 103 | */ |
| 104 | private ExpressionValue getParam(int idx) throws SQLException{ |
| 105 | if(idx < 1 || idx > params.size()) |
| 106 | throw Utils.createSQLException("Parameter index " +idx+ " out of range. The value must be between 1 and " + params.size()); |
| 107 | return ((ExpressionValue)params.get(idx-1)); |
| 108 | } |
| 109 | |
| 110 | /** |
| 111 | * Set value of a PreparedStatement parameter. |
| 112 | * The idx starts with 1. |
| 113 | */ |
| 114 | void setParamValue(int idx, Object value, int dataType) throws SQLException{ |
| 115 | getParam(idx).set( value, dataType ); |
| 116 | if(log.isLogging()){ |
| 117 | log.println("param"+idx+'='+value+"; type="+dataType); |
| 118 | } |
| 119 | } |
| 120 | |
| 121 | /** |
| 122 | * Set value of a PreparedStatement parameter. |
| 123 | * The idx starts with 1. |
| 124 | */ |
| 125 | void setParamValue(int idx, Object value, int dataType, int length) throws SQLException{ |
| 126 | getParam(idx).set( value, dataType, length ); |
| 127 | if(log.isLogging()){ |
| 128 | log.println("param"+idx+'='+value+"; type="+dataType+"; length="+length); |
| 129 | } |
| 130 | } |
| 131 | |
| 132 | final void execute(SSConnection con, SSStatement st) throws SQLException{ |
| 133 | int savepoint = con.getSavepoint(); |
| 134 | try{ |
| 135 | executeImpl( con, st ); |
| 136 | }catch(Throwable e){ |
| 137 | con.rollback(savepoint); |
| 138 | throw Utils.createSQLException(e); |
| 139 | }finally{ |
| 140 | if(con.getAutoCommit()) con.commit(); |
| 141 | } |
| 142 | } |
| 143 | |
| 144 | abstract void executeImpl(SSConnection con, SSStatement st) throws Exception; |
| 145 | |
| 146 | SSResultSet getQueryResult() throws SQLException{ |
| 147 | if(rs == null) |
| 148 | throw Utils.createSQLException("No ResultSet was produce."); |
| 149 | return rs; |
| 150 | } |
| 151 | |
| 152 | SSResultSet getResultSet(){ |
| 153 | return rs; |
| 154 | } |
| 155 | |
| 156 | int getUpdateCount(){ |
| 157 | return updateCount; |
| 158 | } |
| 159 | |
| 160 | |
| 161 | /** |
| 162 | * Set the max rows. Need to be override in the Commands that support it. |
| 163 | */ |
| 164 | void setMaxRows(int max){} |
| 165 | |
| 166 | |
| 167 | int getMaxRows(){return 0;} |
| 168 | } |