1 /**

     2  * SQL-DK

     3  * Copyright © 2013 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.sql.dk;

    19 

    20 import static info.globalcode.sql.dk.Functions.findByName;

    21 import java.sql.Connection;

    22 import java.sql.PreparedStatement;

    23 import java.sql.SQLException;

    24 import java.util.ArrayList;

    25 import java.util.List;

    26 import java.util.logging.Level;

    27 import java.util.logging.Logger;

    28 import java.util.regex.Matcher;

    29 import java.util.regex.Pattern;

    30 import java.util.regex.PatternSyntaxException;

    31 

    32 /**

    33  * Has named parameters.

    34  *

    35  * @author Ing. František Kučera (frantovo.cz)

    36  */

    37 public class SQLCommandNamed extends SQLCommand {

    38 

    39 	private static final Logger log = Logger.getLogger(SQLCommandNamed.class.getName());

    40 	private String namePrefix;

    41 	private String nameSuffix;

    42 	private List<NamedParameter> parameters;

    43 	private List<NamedParameter> parametersUsed = new ArrayList<>();

    44 	private StringBuilder updatedQuery;

    45 	private Pattern pattern;

    46 	private SQLCommandNumbered numbered;

    47 

    48 	public SQLCommandNamed(String query, List<NamedParameter> parameters, String namePrefix, String nameSuffix) {

    49 		super(query);

    50 		this.updatedQuery = new StringBuilder(query.length());

    51 		this.parameters = parameters;

    52 		this.namePrefix = namePrefix;

    53 		this.nameSuffix = nameSuffix;

    54 	}

    55 

    56 	@Override

    57 	public PreparedStatement prepareStatement(Connection c) throws SQLException {

    58 		return getSQLCommandNumbered().prepareStatement(c);

    59 	}

    60 

    61 	@Override

    62 	public void parametrize(PreparedStatement ps) throws SQLException {

    63 		getSQLCommandNumbered().parametrize(ps);

    64 	}

    65 

    66 	private void prepare() throws SQLException {

    67 		try {

    68 			buildPattern();

    69 			placeParametersAndUpdateQuery();

    70 			logPossiblyMissingParameters();

    71 		} catch (PatternSyntaxException e) {

    72 			throw new SQLException("Name prefix „" + namePrefix + "“ or suffix „" + nameSuffix + "“ contain a wrong regular expression. " + e.getLocalizedMessage(), e);

    73 		}

    74 	}

    75 

    76 	/**

    77 	 * @return SQL command with named parameters converted to SQL command with numbered parameters

    78 	 */

    79 	public SQLCommandNumbered getSQLCommandNumbered() throws SQLException {

    80 		if (numbered == null) {

    81 			prepare();

    82 			numbered = new SQLCommandNumbered(updatedQuery.toString(), parametersUsed);

    83 		}

    84 

    85 		return numbered;

    86 	}

    87 

    88 	/**

    89 	 * Builds a regexp pattern that matches all parameter names (with prefix/suffix) and which has

    90 	 * one group: parameter name (without prefix/suffix)

    91 	 */

    92 	private void buildPattern() throws PatternSyntaxException {

    93 		StringBuilder patternString = new StringBuilder();

    94 

    95 		patternString.append(namePrefix);

    96 		patternString.append("(?<paramName>");

    97 		for (int i = 0; i < parameters.size(); i++) {

    98 			patternString.append(Pattern.quote(parameters.get(i).getName()));

    99 			if (i < parameters.size() - 1) {

   100 				patternString.append("|");

   101 			}

   102 		}

   103 		patternString.append(")");

   104 		patternString.append(nameSuffix);

   105 

   106 		pattern = Pattern.compile(patternString.toString());

   107 	}

   108 

   109 	private void placeParametersAndUpdateQuery() {

   110 		final String originalQuery = getQuery();

   111 		Matcher m = pattern.matcher(originalQuery);

   112 

   113 		int lastPosition = 0;

   114 		while (m.find(lastPosition)) {

   115 			String name = m.group("paramName");

   116 

   117 			updatedQuery.append(originalQuery.substring(lastPosition, m.start()));

   118 			updatedQuery.append("?");

   119 

   120 			parametersUsed.add(findByName(parameters, name));

   121 

   122 			lastPosition = m.end();

   123 		}

   124 		updatedQuery.append(originalQuery.substring(lastPosition, originalQuery.length()));

   125 

   126 		for (NamedParameter definedParameter : parameters) {

   127 			if (findByName(parametersUsed, definedParameter.getName()) == null) {

   128 				/**

   129 				 * User can have predefined set of parameters and use them with different SQL

   130 				 * queries that use only subset of these parameters → just warning, not exception.

   131 				 */

   132 				log.log(Level.WARNING, "Parameter „{0}“ is defined but not used in the query: „{1}“", new Object[]{definedParameter.getName(), originalQuery});

   133 			}

   134 		}

   135 	}

   136 

   137 	private void logPossiblyMissingParameters() {

   138 		Pattern p = Pattern.compile(namePrefix + "(?<paramName>.+?)" + nameSuffix);

   139 		Matcher m = p.matcher(updatedQuery);

   140 		int lastPosition = 0;

   141 		while (m.find(lastPosition)) {

   142 			/**

   143 			 * We have not parsed and understood the SQL query; the parameter-like looking string

   144 			 * could be inside a literal part of the query → just warning, not exception.

   145 			 */

   146 			log.log(Level.WARNING, "Possibly missing parameter „{0}“ in the query: „{1}“", new Object[]{m.group("paramName"), getQuery()});

   147 			lastPosition = m.end();

   148 		}

   149 	}

   150 

   151 	@Override

   152 	public List<NamedParameter> getParameters() {

   153 		return parameters;

   154 	}

   155 }