结果集未正确关闭

Question

java prettyprint-override">ResultSet rsSel = null;
// preparated statemen
PreparedStatement stmtSel = null;
// preparated statemen
PreparedStatement stmtUpd = null;
try {
  //create query yyyyyyyy
  String query = SQLStatements.getStatement("queryExample");

  //create PreparedStatement
  stmtSel = (PreparedStatement) conn.prepareStatement(query);

  int index = 1;
  // WHERE:
  stmtSel.setInt(index++, prog);
                                    
  // SELECT:
  rsSel = stmtSel.executeQuery(); //the problem is here
  rsSel.next();  
  //close finally          
  rsSel.close()

finally{
  close(stmtSel);
close(rsSel);
}

               

Closing a result set you left open! Please close it yourself.: java.lang.Throwable: STACKTRACE

有人能帮我吗？

Answer 1

该错误是由太宽的范围、隐藏的异常或控制流中的某些怪癖引起的。最好是使用try-with-resources，它也在返回/中断/异常时关闭。那么你就会：

String query = SQLStatements.getStatement("queryExample");
try (PreparedStatement stmtSel = conn.prepareStatement(query)) {
    int index = 1;
    stmtSel.setInt(index++, prog);
    ...
    try (ResultSet rsSel = stmtSel.executeQuery()) {
        if (rsSel.next()) {
            ...
        }
    } // Closes rsSel
} // Closes stmtSel

假设导入java.sql.PreparedStatement,则不需要转换为PreparedStatement。

对了：