java - 用于附加代码的 StringBuffer 或 HashMap？

Question

StringBuffer 或 HashMap

这是附加代码的最佳方式，并且还可以提高性能。

StringBuffer sql = new StringBuffer();
DBDatabase db = UTIL.getDatabase();
sql.append("SELECT I.FLDCODE, I.FLDDESCR, I.FLDWORKPHON FROM ");
sql.append(db.getSchema());
sql.append("TRNINSTR I, ");
sql.append(db.getSchema());
sql.append("TRNCRSIN C WHERE C.FLDCOURSE = ? AND C.FLDINSTRUCT = I.FLDCODE AND (I.FLDINACTIVE IS NULL OR I.FLDINACTIVE <> 'y') ORDER BY C.FLDSEQUENCE");
DBPreparedStatement stmt = new DBPreparedStatement(db, sql, "TrainPage.getInfoInstrList");
stmt.setString(1, courseType);
DBResultSet rs = stmt.executeQuery();
stmt.close();

Answer 1

StringBuilder表现甚至更好。请记住，缓慢的部分是数据库访问而不是语句准备。