Code reviewMediumcr-g199

Subject Connection leakLevel Mid–Senior~25 minCommon in Code quality & review interviewsIndustries Software development

Question

Review this Java method that reads a config value from a pooled DataSource.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.

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Code to reviewjava

1String lookupFlag(DataSource ds, String key) throws SQLException {2    Connection conn = ds.getConnection();3    PreparedStatement ps = conn.prepareStatement(4        "SELECT value FROM flags WHERE key = ?");5    ps.setString(1, key);6    ResultSet rs = ps.executeQuery();7    if (rs.next()) {8        String v = rs.getString("value");9        conn.close();10        return v;11    }12    conn.close();13    return null;14}

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