001    //$HeadURL: svn+ssh://jwilden@svn.wald.intevation.org/deegree/base/branches/2.5_testing/src/org/deegree/io/datastore/schema/content/SQLFunctionCall.java $
002    /*----------------------------------------------------------------------------
003     This file is part of deegree, http://deegree.org/
004     Copyright (C) 2001-2009 by:
005       Department of Geography, University of Bonn
006     and
007       lat/lon GmbH
008    
009     This library is free software; you can redistribute it and/or modify it under
010     the terms of the GNU Lesser General Public License as published by the Free
011     Software Foundation; either version 2.1 of the License, or (at your option)
012     any later version.
013     This library is distributed in the hope that it will be useful, but WITHOUT
014     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
015     FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
016     details.
017     You should have received a copy of the GNU Lesser General Public License
018     along with this library; if not, write to the Free Software Foundation, Inc.,
019     59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
020    
021     Contact information:
022    
023     lat/lon GmbH
024     Aennchenstr. 19, 53177 Bonn
025     Germany
026     http://lat-lon.de/
027    
028     Department of Geography, University of Bonn
029     Prof. Dr. Klaus Greve
030     Postfach 1147, 53001 Bonn
031     Germany
032     http://www.geographie.uni-bonn.de/deegree/
033    
034     e-mail: info@deegree.org
035    ----------------------------------------------------------------------------*/
036    package org.deegree.io.datastore.schema.content;
037    
038    import java.util.HashSet;
039    import java.util.List;
040    import java.util.Set;
041    
042    import org.deegree.io.datastore.schema.MappedSimplePropertyType;
043    
044    /**
045     * Content class for {@link MappedSimplePropertyType}s that describes a call to a function provided
046     * by an SQL database.
047     *
048     * @author <a href="mailto:schneider@lat-lon.de">Markus Schneider</a>
049     * @author last edited by: $Author: mschneider $
050     *
051     * @version $Revision: 18195 $, $Date: 2009-06-18 17:55:39 +0200 (Do, 18 Jun 2009) $
052     */
053    public class SQLFunctionCall extends FunctionCall {
054    
055        private String callString;
056    
057        private int typeCode;
058    
059        private int[] usedVarNumbers;
060    
061        /**
062         * Initializes a newly created <code>SQLFunctionCall</code> with the given call string and
063         * {@link FunctionParam}s.
064         *
065         * @param callString
066         *            call string with placeholders ($1,$2,...,$n)
067         * @param typeCode
068         *            SQL type code of the return value
069         * @param params
070         *            parameters to be used for the placeholders
071         */
072        public SQLFunctionCall( String callString, int typeCode, List<FunctionParam> params ) {
073            super( params );
074            this.callString = callString;
075            this.typeCode = typeCode;
076            this.usedVarNumbers = extractUsedVars( callString );
077        }
078    
079        /**
080         * Initializes a newly created <code>SQLFunctionCall</code> with the given call string and
081         * {@link FunctionParam}s.
082         *
083         * @param callString
084         *            call string with placeholders ($1,$2,...,$n)
085         * @param typeCode
086         *            SQL type code of the return value
087         * @param params
088         *            parameters to be used for the placeholders
089         */
090        public SQLFunctionCall( String callString, int typeCode, FunctionParam... params ) {
091            super( params );
092            this.callString = callString;
093            this.typeCode = typeCode;
094            this.usedVarNumbers = extractUsedVars( callString );
095        }
096    
097        /**
098         * Extracts all variable numbers ('$i') used in the given call string.
099         *
100         * @param callString
101         * @return all variable numbers used in the given call string
102         */
103        private int[] extractUsedVars( String callString ) {
104    
105            Set<Integer> usedVars = new HashSet<Integer>();
106    
107            int foundAt = callString.indexOf( '$' );
108            while ( foundAt != -1 ) {
109                foundAt++;
110                String varNumberString = "";
111                while ( foundAt < callString.length() ) {
112                    char numberChar = callString.charAt( foundAt++ );
113                    if ( numberChar >= '0' && numberChar <= '9' ) {
114                        varNumberString += numberChar;
115                    } else {
116                        break;
117                    }
118                }
119    
120                assert varNumberString.length() != 0;
121    
122                try {
123                    int varNo = Integer.parseInt( varNumberString );
124                    assert varNo != 0;
125                    usedVars.add( varNo );
126                } catch ( NumberFormatException e ) {
127                    assert false;
128                }
129    
130                // find next '$' symbol
131                foundAt = callString.indexOf( '$', foundAt );
132            }
133    
134            int[] usedVarInts = new int[usedVars.size()];
135            int i = 0;
136            for ( Integer pos : usedVars ) {
137                usedVarInts[i++] = pos;
138            }
139    
140            return usedVarInts;
141        }
142    
143        /**
144         * Returns true, because the result of an SQL function call is (in general) suitable as a sort
145         * criterion.
146         *
147         * @return true, because the result of an SQL function call is (in general) suitable as a sort
148         *         criterion
149         */
150        public boolean isSortable() {
151            return true;
152        }
153    
154        /**
155         * Returns the call string with placeholders ($1,$2,...,$n) for the {@link FunctionParam}s.
156         *
157         * @return the call string with placeholders ($1,$2,...,$n)
158         */
159        public String getCall() {
160            return this.callString;
161        }
162    
163        /**
164         * Returns the SQL type code of the function call's return value.
165         *
166         * @return the SQL type code of the function call's return value.
167         */
168        public int getTypeCode() {
169            return this.typeCode;
170        }
171    
172        /**
173         * Returns all variable numbers used in the call string.
174         *
175         * @return all variable numbers used in the call string
176         */
177        public int[] getUsedVars() {
178            return this.usedVarNumbers;
179        }
180    
181        @Override
182        public String toString() {
183            String s = this.callString;
184            int[] usedVars = this.getUsedVars();
185            List<FunctionParam> params = this.getParams();
186            for ( int j = 0; j < usedVars.length; j++ ) {
187                int varNo = usedVars[j];
188                String varString = "\\$" + varNo;
189                FunctionParam param = params.get( varNo - 1 );
190                if ( param instanceof FieldContent ) {
191                    String replace = ( (FieldContent) param ).getField().getTable() + "."
192                                     + ( (FieldContent) param ).getField().getField();
193                    s = s.replaceAll( varString, replace );
194                } else if ( param instanceof ConstantContent ) {
195                    String replace = ( (ConstantContent) param ).getValue();
196                    s = s.replaceAll( varString, replace );
197                } else if ( param instanceof SpecialContent ) {
198    //                appendSpecialContentValue( query, (SpecialContent) param );
199    //                s = s.replaceFirst( varString, "?" );
200                } else {
201                    assert false;
202                }
203            }
204            return s;
205        }
206    }