Java RedshiftClient 封装

package com.lattice.qa.common;
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
 
public class RedshiftClient {
    private Connection con = null;
    private Statement stmt = null;
 
    public RedshiftClient(String dbURL, String userName, String password) throws SQLException {
        setupDBConnection(dbURL, userName, password);
    }
 
    public RedshiftClient() throws SQLException {
        setupDBConnection(Environment.INSTANCE.getValueByEnv("cdl.redShiftDBUrl"),
                Environment.INSTANCE.getValueByEnv("cdl.redShiftDBUser"),
                Environment.INSTANCE.getValueByEnv("cdl.redShiftDBPWD"));
    }
 
    ///
    // IsClose() is only guaranteed to return true if the connection was closed by a
    /// call to Connection.close(). If the connection wa