问题[jdbc]

我正在 servlet 上编写一个简单的 java web 应用程序。堆栈：JDBC、Postgres、Maven、Tomcat。我遇到了数据库查询的问题。我使用通配符形成查询字符串：

String query = "SELECT * FROM parts WHERE partname LIKE (?) AND partnumber LIKE (?) AND vendor LIKE (?) AND qty >= (?) AND (shipped BETWEEN (?) AND (?) OR shipped IS NULL) AND (receive BETWEEN (?) AND (?) OR receive IS NULL)"

接下来，我放下参数statment.setDate()。这里有一个错误。变量 shBf 和 rcBf 设置为“2019-12-31”，preparedParameters 设置为“2019-01-31”。这是什么魔法？我没有在代码中看到错误，但它在某个地方。我真的不相信图书馆中的错误。很可能我做错了什么。我请求你的帮助。我还附上了一些代码。如果需要，准备发布更多。

package app.jdbc;

import app.models.Filter;
import app.entities.Part;

import java.sql.*;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.List;

public class RepositoryImpl implements Repository {
    private final Connection connection;

    public RepositoryImpl(Connection connection) {
        this.connection = connection;
    }

    public List<Part> getListOfParts(Filter filter) {
//        SELECT * FROM parts WHERE partname LIKE '%lade%' AND partnumber LIKE '%2%' AND vendor LIKE '%steel%' AND qty >= 5
//        shipped BETWEEN '2019-01-08' AND '2019-12-31' AND receive BETWEEN '2019-01-30' AND '2019-03-31'
        String qty = filter.getQty();
        Filter.TimeRange received = filter.getReceived();
        Filter.TimeRange shipped = filter.getShipped();
        int qtyInt = qty.equals("") ? 0: Integer.parseInt(qty);
        String shAf = shipped.getAfter().equals("") ? "1970-01-01": shipped.getAfter();
        String shBf = shipped.getBefore().equals("") ? "2099-12-31": shipped.getBefore();
        String rcAf = received.getAfter().equals("") ? "1970-01-01": received.getAfter();
        String rcBf = received.getBefore().equals("") ? "2099-12-31": received.getBefore();
        String query = "SELECT * FROM parts WHERE partname LIKE (?) AND partnumber LIKE (?) AND vendor LIKE (?) " +
                "AND qty >= (?) AND (shipped BETWEEN (?) AND (?) OR shipped IS NULL) " +
                "AND (receive BETWEEN (?) AND (?) OR receive IS NULL)";
        List<Part> parts = new ArrayList<>();
        try (PreparedStatement statement = connection.prepareStatement(query)){
            statement.setString(1, "%" + filter.getPartName() + "%");
            statement.setString(2, "%" + filter.getPartNumber() + "%");
            statement.setString(3, "%" + filter.getVendor() + "%");
            statement.setInt(4, qtyInt);
            statement.setDate(5, new Date(new SimpleDateFormat("yyyy-mm-dd").parse(shAf).getTime()));
            statement.setDate(6, new Date(new SimpleDateFormat("yyyy-mm-dd").parse(shBf).getTime()));
            statement.setDate(7, new Date(new SimpleDateFormat("yyyy-mm-dd").parse(rcAf).getTime()));
            statement.setDate(8, new Date(new SimpleDateFormat("yyyy-mm-dd").parse(rcBf).getTime()));
            final ResultSet resultSet = statement.executeQuery();
            while (resultSet.next()) {
                parts.add(new Part(resultSet.getString("partname"),
                        resultSet.getString("partnumber"),
                        resultSet.getString("vendor"),
                        resultSet.getInt("qty"),
                        resultSet.getString("shipped"),
                        resultSet.getString("receive")
                        ));
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } catch (ParseException e) {
            e.printStackTrace();
        }
        return parts;
    }
}

package app.models;

public class Filter {
    String partName, partNumber, vendor;
    String qty;
    TimeRange shipped, received;

    public Filter(String partName, String partNumber, String vendor, String qty, TimeRange shipped, TimeRange received) {
        this.partName = partName;
        this.partNumber = partNumber;
        this.vendor = vendor;
        this.qty = qty;
        this.shipped = shipped;
        this.received = received;
    }

    public TimeRange getShipped() {
        return shipped;
    }

    public void setShipped(TimeRange shipped) {
        this.shipped = shipped;
    }

    public TimeRange getReceived() {
        return received;
    }

    public void setReceived(TimeRange received) {
        this.received = received;
    }

    public String getPartName() {
        return partName;
    }

    public void setPartName(String partName) {
        this.partName = partName;
    }

    public String getPartNumber() {
        return partNumber;
    }

    public void setPartNumber(String partNumber) {
        this.partNumber = partNumber;
    }

    public String getVendor() {
        return vendor;
    }

    public void setVendor(String vendor) {
        this.vendor = vendor;
    }

    public String getQty() {
        return qty;
    }

    public void setQty(String qty) {
        this.qty = qty;
    }

    public static class TimeRange {
        private String after;
        private String before;

        public TimeRange(String after, String before) {
            this.after = after;
            this.before = before;
        }

        public String getAfter() {
            return after;
        }

        public void setAfter(String after) {
            this.after = after;
        }

        public String getBefore() {
            return before;
        }

        public void setBefore(String before) {
            this.before = before;
        }
    }
}

谁知道如何在查询中使用 Jmeter 中的数据库中的数据？例如，有一个步骤 - 通过 JDBC 从数据库中选择前提条件，然后有一个 http 请求 - 我想在其中替换这些值。而且，如果有多个流，那么数据库中的值必须不重复（类比从csv读取）。