001    /*
002     $Id: DataSet.java,v 1.8 2004/05/15 04:53:01 bran Exp $
003    
004     Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
005    
006     Redistribution and use of this software and associated documentation
007     ("Software"), with or without modification, are permitted provided
008     that the following conditions are met:
009    
010     1. Redistributions of source code must retain copyright
011        statements and notices.  Redistributions must also contain a
012        copy of this document.
013    
014     2. Redistributions in binary form must reproduce the
015        above copyright notice, this list of conditions and the
016        following disclaimer in the documentation and/or other
017        materials provided with the distribution.
018    
019     3. The name "groovy" must not be used to endorse or promote
020        products derived from this Software without prior written
021        permission of The Codehaus.  For written permission,
022        please contact info@codehaus.org.
023    
024     4. Products derived from this Software may not be called "groovy"
025        nor may "groovy" appear in their names without prior written
026        permission of The Codehaus. "groovy" is a registered
027        trademark of The Codehaus.
028    
029     5. Due credit should be given to The Codehaus -
030        http://groovy.codehaus.org/
031    
032     THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
033     ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
034     NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
035     FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
036     THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
037     INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
038     (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
039     SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
040     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
041     STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
042     ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
043     OF THE POSSIBILITY OF SUCH DAMAGE.
044    
045     */
046    package groovy.sql;
047    
048    import groovy.lang.Closure;
049    import groovy.lang.GroovyRuntimeException;
050    
051    import java.sql.Connection;
052    import java.sql.PreparedStatement;
053    import java.sql.SQLException;
054    import java.util.ArrayList;
055    import java.util.Iterator;
056    import java.util.List;
057    import java.util.Map;
058    import java.util.logging.Level;
059    
060    import org.codehaus.groovy.ast.ClassNode;
061    import org.codehaus.groovy.ast.MethodNode;
062    import org.codehaus.groovy.ast.stmt.Statement;
063    
064    /**
065     * Represents an extent of objects
066     * 
067     * @author Chris Stevenson
068     * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
069     * @version $Revision: 1.8 $
070     */
071    public class DataSet extends Sql {
072    
073        private Closure where;
074        private DataSet parent;
075        private String table;
076        private SqlWhereVisitor visitor;
077        private String sql;
078        private List params;
079    
080        public DataSet(Sql sql, Class type) {
081            super(sql);
082            String table = type.getName();
083            int idx = table.lastIndexOf('.');
084            if (idx > 0) {
085                table = table.substring(idx + 1);
086            }
087            this.table = table.toLowerCase();
088        }
089    
090        public DataSet(Sql sql, String table) {
091            super(sql);
092            this.table = table;
093        }
094    
095        public DataSet(DataSet parent, Closure where) {
096            super(parent);
097            this.table = parent.table;
098            this.parent = parent;
099            this.where = where;
100        }
101    
102        public void add(Map values) throws SQLException {
103            StringBuffer buffer = new StringBuffer("insert into ");
104            buffer.append(table);
105            buffer.append(" (");
106            StringBuffer paramBuffer = new StringBuffer();
107            boolean first = true;
108            for (Iterator iter = values.entrySet().iterator(); iter.hasNext();) {
109                Map.Entry entry = (Map.Entry) iter.next();
110                String column = entry.getKey().toString();
111                if (first) {
112                    first = false;
113                    paramBuffer.append("?");
114                }
115                else {
116                    buffer.append(", ");
117                    paramBuffer.append(", ?");
118                }
119                buffer.append(column);
120            }
121            buffer.append(") values (");
122            buffer.append(paramBuffer.toString());
123            buffer.append(")");
124    
125            Connection connection = createConnection();
126            PreparedStatement statement = null;
127            try {
128                statement = connection.prepareStatement(buffer.toString());
129                int i = 1;
130                for (Iterator iter = values.entrySet().iterator(); iter.hasNext();) {
131                    Map.Entry entry = (Map.Entry) iter.next();
132                    setObject(statement, i++, entry.getValue());
133                }
134                int answer = statement.executeUpdate();
135                if (answer != 1) {
136                    log.log(Level.WARNING, "Should have updated 1 row not " + answer + " when trying to add: " + values);
137                }
138            }
139            catch (SQLException e) {
140                log.log(Level.WARNING, "Failed to add row for: " + values, e);
141                throw e;
142            }
143            finally {
144                closeResources(connection, statement);
145            }
146        }
147    
148        public DataSet findAll(Closure where) {
149            return new DataSet(this, where);
150        }
151    
152        public void each(Closure closure) throws SQLException {
153            eachRow(getSql(), getParameters(), closure);
154        }
155    
156        public String getSql() {
157            if (sql == null) {
158                sql = "select * from " + table;
159                if (where != null) {
160                    String clause = "";
161                    if (parent != null && parent.where != null) {
162                        clause += parent.getSqlVisitor().getWhere() + " and ";
163                    }
164                    clause += getSqlVisitor().getWhere();
165                    if (clause.length() > 0) {
166                        sql += " where " + clause;
167                    }
168                }
169            }
170            return sql;
171        }
172    
173        public List getParameters() {
174            if (params == null) {
175                params = new ArrayList();
176                if (parent != null && parent.where != null) {
177                    params.addAll(parent.getParameters());
178                }
179                params.addAll(getSqlVisitor().getParameters());
180            }
181            return params;
182        }
183    
184        protected SqlWhereVisitor getSqlVisitor() {
185            if (visitor == null) {
186                visitor = new SqlWhereVisitor();
187                if (where != null) {
188                    ClassNode classNode = where.getMetaClass().getClassNode();
189                    if (classNode == null) {
190                        throw new GroovyRuntimeException(
191                            "Could not find the ClassNode for MetaClass: " + where.getMetaClass());
192                    }
193                    List methods = classNode.getDeclaredMethods("doCall");
194                    if (!methods.isEmpty()) {
195                        MethodNode method = (MethodNode) methods.get(0);
196                        if (method != null) {
197                            Statement statement = method.getCode();
198                            if (statement != null) {
199                                statement.visit(visitor);
200                            }
201                        }
202                    }
203                }
204            }
205            return visitor;
206        }
207        /*
208         * create a subset of the original dataset
209         */
210        public DataSet createView(Closure criteria) {
211            return new DataSet(this, criteria);
212        }
213    }