sascha@372: package de.intevation.flys.artifacts.services.meta;
sascha@372: 
sascha@372: import java.util.regex.Pattern;
sascha@372: import java.util.regex.Matcher;
sascha@372: 
sascha@372: import java.util.List;
sascha@372: import java.util.Map;
sascha@372: import java.util.HashMap;
sascha@372: import java.util.ArrayList;
sascha@372: 
sascha@372: import java.sql.PreparedStatement;
sascha@372: import java.sql.SQLException;
sascha@372: import java.sql.Connection;
sascha@372: import java.sql.ResultSet;
sascha@372: 
sascha@372: public class CompiledStatement
sascha@372: {
sascha@372:     public static final Pattern VAR = Pattern.compile("\\$\\{([a-zA-Z0-9_]+)\\}");
sascha@372: 
sascha@372:     protected String original;
sascha@372:     protected String statement;
sascha@372: 
sascha@372:     protected Map<String, List<Integer>> positions;
sascha@372: 
sascha@372:     protected PreparedStatement preparedStatement;
sascha@372: 
sascha@372:     public CompiledStatement() {
sascha@372:     }
sascha@372: 
sascha@372:     public CompiledStatement(String original) {
sascha@372:         this.original = original;
sascha@372:         positions = new HashMap<String, List<Integer>>();
sascha@372:         compile();
sascha@372:     }
sascha@372: 
sascha@372:     protected void compile() {
sascha@372: 
sascha@372:         StringBuffer sb = new StringBuffer();
sascha@372: 
sascha@372:         Matcher m = VAR.matcher(original);
sascha@372: 
sascha@372:         int index = 1;
sascha@372: 
sascha@372:         while (m.find()) {
sascha@372:             String key = m.group(1);
sascha@372:             List<Integer> indices = positions.get(key);
sascha@372:             if (indices == null) {
sascha@372:                 indices = new ArrayList<Integer>();
sascha@372:                 positions.put(key, indices);
sascha@372:             }
sascha@372:             indices.add(index);
sascha@372:             m.appendReplacement(sb, "?");
sascha@372:             ++index;
sascha@372:         }
sascha@372: 
sascha@372:         m.appendTail(sb);
sascha@372: 
sascha@372:         statement = sb.toString();
sascha@372:     }
sascha@372: 
sascha@372:     public String getStatement() {
sascha@372:         return statement;
sascha@372:     }
sascha@372: 
sascha@372:     public ResultData execute(Connection connection, StackFrames frames) 
sascha@372:     throws SQLException
sascha@372:     {
sascha@372:         if (preparedStatement == null) {
sascha@372:             preparedStatement = connection.prepareStatement(statement);
sascha@372:         }
sascha@372: 
sascha@372:         for (Map.Entry<String, List<Integer>> entry: positions.entrySet()) {
sascha@372:             Object value = frames.get(entry.getKey());
sascha@372:             for (Integer index: entry.getValue()) {
sascha@372:                 preparedStatement.setObject(index, value);
sascha@372:             }
sascha@372:         }
sascha@372: 
sascha@372:         ResultSet result = preparedStatement.executeQuery();
sascha@372:         try {
sascha@372:             return new ResultData(preparedStatement.getMetaData())
sascha@372:                 .addAll(result);
sascha@372:         }
sascha@372:         finally {
sascha@372:             result.close();
sascha@372:         }
sascha@372:     }
sascha@372: 
sascha@372:     public void close() {
sascha@372:         if (preparedStatement != null) {
sascha@372:             try {
sascha@372:                 preparedStatement.close();
sascha@372:             }
sascha@372:             catch (SQLException sqle) {
sascha@372:             }
sascha@372:             preparedStatement = null;
sascha@372:         }
sascha@372:     }
sascha@372: }
sascha@372: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :