java中的突然结果集行为

在过去的2-3天里，我遇到了一个问题。这似乎是个小问题，但我一直没能抓住

问题在于代码中的resultset rs方法mergeTable中的while（rs.next（））语句行为异常。在某些情况下，它第一次进入while循环，有时不进入，在少数情况下，当它进入while循环时，它会突然抛出resultset depened exception。我在谷歌上搜索，发现结果集可能已经被其他访问代码的线程关闭了。但这是一个简单的独立java应用程序，不是多线程的

我还要注意另外两个结果集，check和checktarget不会干扰结果集rs。我还要关闭语句和结果集。 请你看一下代码，看看我是否遗漏了什么

正在使用的两个数据库实例是10.180.22.93:1521:V3demo（称为源数据库）和10.180.22.93:1521:fusiondb（称为目标数据库）。rs resultset来自源数据库。resultset check和checktarget来自目标数据库。因此，结果集rs将来自源数据库的表A，而结果集check和checktarget将来自目标数据库的表A

    static String mergeTable() throws Exception {
    String result = "ERROR";
    int error = 0;
    String tableString = "<table " + tablename + ">";

    PreparedStatement preparedSelect = null;
    PreparedStatement preparedSelectTarget = null;
    Statement selectSourceStmt = null;
    ResultSet checkTarget = null;
    ResultSet rs = null;
    try {

        logger.println("====================================================================================");
        logger.println("Processing table:" + tablename);
        System.out.println("====================================================================================");
        System.out.println("Processing table:" + tablename);

        // Create query to fetch records from the source
        String sourceQuery = "SELECT * FROM " + tablename;
        if (owner.trim().equals("F1") || owner.trim().equals("C1") || owner.trim().equals("CM"))
            sourceQuery = sourceQuery + " WHERE OWNER_FLG='" + owner + "'";

        // Get the result set

        selectSourceStmt = source.createStatement();
        rs = selectSourceStmt.executeQuery(sourceQuery);

        System.out.println(sourceQuery);

        String selectSQL = "SELECT COUNT(*) FROM " + tablename + " WHERE ";
        String selectSQLTarget = "SELECT * FROM " + tablename + " WHERE "; // ankush

        ResultSetMetaData metaData = rs.getMetaData();

        List list = new ArrayList();
        List typesList = new ArrayList();

        for (int i = 1; i <= metaData.getColumnCount(); i++) {
            String columnName = metaData.getColumnName(i);
            list.add(columnName); // list contains the entire list of columns of the source
            typesList.add(metaData.getColumnType(i));

        }

        for (int i = 1; i < keys.length; i++) {

            if (i == 1) {
                selectSQL = selectSQL + " " + keys[i] + "= ?";
                selectSQLTarget = selectSQLTarget + " " + keys[i] + "= ?"; //ankush 
            }

            else {
                selectSQL = selectSQL + " AND " + keys[i] + "= ?";
                selectSQLTarget = selectSQLTarget + " AND " + keys[i] + "= ?"; //ankush
            }

        }

        logger.println("Select SQL:" + selectSQL);
        logger.println("selectSQLTarget:" + selectSQLTarget); //ankush

        preparedSelect = target.prepareStatement(selectSQL);
        preparedSelectTarget = target.prepareStatement(selectSQLTarget); //ankush

        int updateCount = 0, insertCount = 0, errorCount = 0;
        // rs contains the entire table snapshot of source  based on the owner flag
        if (rs != null) {

            while (rs.next()) {
                try {
                    int i, count;

                    // check if record exists or not; keys contain the values of primary columns specified in the.lst file
                    for (int j = 1; j < keys.length; j++) {
                        preparedSelect.setObject(j, rs.getObject(keys[j])); // for every single row in source, corresponding rows are fetched from target.Here, where clause is being prepared

                    }

                    ResultSet check = preparedSelect.executeQuery(); // check is the target resultset for the primary key values in current row of source resultset

                    check.next();

                    count = check.getInt(1); // count gives the row/s fetched from target based on the values in source.
                    check.close();

                    // check if record exists or not; keys contain the values of primary columns specified in the.lst file
                    for (int j = 1; j < keys.length; j++) {
                        // for every single row in source, corresponding rows are fetched from target.Here, where clause is being prepared
                        preparedSelectTarget.setObject(j, rs.getObject(keys[j]));

                    }

                    // check is the target resultset for the primary key values in current row of source resultset  
                    checkTarget = preparedSelectTarget.executeQuery();

                    checkTarget.next();

                    // if record exists  UPDATE CONDITION
                    if (true) { // if there is a record in target for a row in source, update target
                        String rowString = "<row>";
                        String rowDiffFlag = "N";
                        // if merge flag is Y
                        if (mergeFlag.equals("Y")) {
                            String colDiffFlag = "";
                            String sourceColVal = "";
                            String targetColVal = "";
                            // list contains the column names
                            for (i = 0; i < list.size(); i++) {
                                System.out.println("value of i " + i);
                            }
                            i++; // ?????

                        } else {
                                logger.print("Did not update Record:");


                        }
                        rowString = rowString + "</row>";

                        if (rowDiffFlag.equals("Y")) {
                            tableString = tableString + rowString;
                        }

                    } else { // if there is no record in target for a row in source, insert into target
                        String sourceColVal = "";
                        String rowString = "<row>";
                        for (i = 0; i < list.size(); i++) { //looping through columns in a row
                            System.out.println("column " + i);
                            }

                        rowString = rowString + "</row>";
                        tableString = tableString + rowString;
                    }

                } catch (Exception e1) {

                    e1.printStackTrace(logger);

                }
            }
        }

    } catch (Exception e) {

        e.printStackTrace(logger);

    } finally {
        preparedSelect.close();
        preparedSelectTarget.close();
        selectSourceStmt.close();
        checkTarget.close();
        rs.close();
    }

    tableString = tableString + "</table>";
    formXmlString(tableString);

    if (error == 0) result = "SUCCESS";

    return result;
}

静态字符串mergeTable（）引发异常{
字符串result=“ERROR”；
整数误差=0；
字符串tableString=“”；
PreparedStatement preparedSelect=null；
PreparedStatement preparedSelectTarget=null；
语句selectSourceStmt=null；
ResultSet checkTarget=null；
结果集rs=null；
试一试{
logger.println（“===========================================================================================================================================”）；
logger.println（“处理表：“+tablename”）；
System.out.println（“========================================================================================================================================================================================================================================”；
System.out.println（“处理表：“+tablename”）；
//创建查询以从源获取记录
String sourceQuery=“SELECT*FROM”+表名；
如果（owner.trim（）.equals（“F1”）| | owner.trim（）.equals（“C1”）| | owner.trim（）.equals（“CM”））
sourceQuery=sourceQuery+“其中OWNER_FLG=”“+OWNER+””；
//获取结果集
选择sourcestmt=source.createStatement（）；
rs=selectSourceStmt.executeQuery（sourceQuery）；
System.out.println（sourceQuery）；
String selectSQL=“从“+tablename+”WHERE”中选择计数（*）；
String selectSQLTarget=“SELECT*FROM”+tablename+“WHERE”；//ankush
ResultSetMetaData元数据=rs.getMetaData（）；
列表=新的ArrayList（）；
列表类型列表=新的ArrayList（）；
对于（inti=1；i噢，天哪，这里的内容太多了。我看到HTML和JDBC代码混合在一起。这是个坏主意

数据库连接不是线程安全的。您说您正在注意确保您的结果集不受干扰，但此错误表明情况并非如此。我将重构此代码以隔离持久性并使每件事情变得更简单。这在我看来是错误的，但我不愿意仔细研究它以找出原因。
您确定吗e resultset耗尽异常在rs resultset上，而不是在其他两个可能的resultset上：check和checkTarget？
你能缩小你的问题吗？不太可能有人通读所有代码。缩小..而rs.next循环在mergetable方法中..我正在写入一个包含节点的文本文件，节点由c决定正在对数据库实例上的表（具有相同名称）的各个列进行比较。只是想一想：由于这些语句位于同一个表上，准备好的语句是否会产生干扰。preparedSelect=target.prepareStatement（selectSQL）；preparedSelectTarget=target.prepareStatement（selectSQLTarget）；