java.sql.SQLException: 结果集关闭
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/21728494/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
java.sql.SQLException: ResultSet closed
提问by Laxmeena
I cant not do the further process because I get ResultSet closed while running this code. I am adding the value after 15 row of the sqlite database table and I want to find average value of 15 row and that should be store in ArrayList.
我不能做进一步的处理，因为我在运行此代码时关闭了 ResultSet。我在 sqlite 数据库表的 15 行之后添加值，我想找到 15 行的平均值，并且应该存储在 ArrayList 中。
Here is the code:-
这是代码：-
try {
Class.forName("org.sqlite.JDBC");
c = DriverManager.getConnection("jdbc:sqlite:test.db");
c.setAutoCommit(false);
System.out.println("Opened database successfully3");
stmt = c.createStatement();
rs = stmt
.executeQuery("SELECT TIME,BID,ASK FROM '" + title + "' ;");
System.out.println("Opened database successfully 20");
while (rs.next()) {
i++;
System.out.println(i);
if (i > 15) {
System.out.println("i am in");
List<String> stocklist = new ArrayList<String>();
String main = rs.getString(1);
System.out.println(rs.getString(1));
String s[] = main.split(" ", 2);
String date = s[0];
String time = s[1];
stocklist.add(date);
stocklist.add(time);
stocklist.add(df.format(rs.getFloat("BID")));
stocklist.add(df.format(rs.getFloat("ASK")));
rs1 = stmt
.executeQuery("SELECT ASK FROM '" + title + "' ;");
int j = 1;
while (rs1.next()) {
if (j < i) {
System.out.println(rs1.getFloat("ASK"));
avg = avg + rs1.getFloat("ASK");
}
j++;
}
rs1.close();
System.out.println("i am out");
avg = avg / 15;
changepercent = ((rs.getFloat("ASK") - avg) / avg) * 100;
stocklist.add(df.format(changepercent));
stocklist.add("ETE");
stocklist.add("HUN");
stocklist.add("ALU");
stocklist.add("ETE");
stocklist.add("HUN");
stocklist.add("ALU");
stocklist.add("ETE");
stocklist.add("HUN");
hntm.addRow(stocklist);
}
}
rs.close();
stmt.close();
c.close();
} catch (Exception e) {
System.err.println(e.getClass().getName() + ": " + e.getMessage());
System.exit(0);
}
采纳答案by Simulant
you should not reuse a Statement. When you create a new Query, you need so use a new Statement Object. Replace rs1 = stmt.executeQuery("SELECT ASK FROM '" + title + "' ;");with rs1=c.createStatement().executeQuery("SELECT ASK FROM '" + title + "' ;");
您不应该重复使用 Statement。创建新查询时，您需要使用新的语句对象。替换rs1 = stmt.executeQuery("SELECT ASK FROM '" + title + "' ;");为rs1=c.createStatement().executeQuery("SELECT ASK FROM '" + title + "' ;");
回答by thiagola92
This is not the answer for this question, but i was also having problem with java.sql.SQLException: ResultSet closed.
这不是这个问题的答案，但我也遇到了java.sql.SQLException: ResultSet closed.
In my case the result from the query was empty, so the ResultSet returned closed.
在我的情况下，查询结果为空，因此 ResultSet 返回关闭。
PreparedStatement preparedStatement = connection.prepareStatement(sql);
preparedStatement.setString(1, email);
ResultSet resultSet = preparedStatement.executeQuery();
// resultSet closed == didn't find anything
if(resultSet.isClosed())
return false;
