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copied!<p>This is a dastardly devious problem, thankfully it's pretty easy to cope with:</p> <pre><code>public class PreparedStatementBuilder { private String sql; // the sql to be executed public PreparedStatementBuilder(final String sql) { this.sql = sql; } protected void preparePrepared(final PreparedStatement preparedStatement) throws SQLException { // this virtual method lets us declare how, when we do generate our // PreparedStatement, we want it to be setup. // note that at the time this method is overridden, the // PreparedStatement has not yet been created. } public PreparedStatement build(final Connection conn) throws SQLException { // fetch the PreparedStatement final PreparedStatement returnable = conn.prepareStatement(sql); // perform our setup directives preparePrepared(returnable); return returnable; } } </code></pre> <p>To use, just write an anonymous class that overrides void preparePrepared(PreparedStatement):</p> <pre><code> final String sql = "SELECT * FROM FOO WHERE USER = ?"; PreparedStatementBuilder psBuilder = new PreparedStatementBuilder(sql){ @Override protected void preparePrepared(PreparedStatement preparedStatement) throws SQLException { preparedStatement.setString(1, "randal"); }}; return obtainResultSet(psBuilder); </code></pre> <p>Presto! You now have a way to work with a PreparedStatement without yet having built it. Here's an example showing the minimal boilerplate you'd otherwise have to copy paste to kingdom come, every time you wanted to write a different statement: </p> <pre><code>public ResultSet obtainResultSet(final PreparedStatementBuilder builder) throws SQLException { final Connection conn = this.connectionSource.getConnection(); try { // your "virtual" preparePrepared is called here, doing the work // you've laid out for your PreparedStatement now that it's time // to actually build it. return builder.build(conn).executeQuery(); } finally { try { conn.close(); } catch (SQLException e) { log.error("f7u12!", e); } } } </code></pre> <p>You really really don't want to be copy pasting that everywhere, do you?</p>

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