Java连接Oracle

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.junit.Test;

import com.app.config.Const;

public class DBHelper_Oracle {
    private static final Logger logger = LogManager
            .getLogger(DBHelper_Oracle.class);

    static String driver = "oracle.jdbc.driver.OracleDriver";
    static String url = Const.DBURL;

    protected static Connection getDBConnection(String url, String userName,
            String password) {
        Connection con = null;
        try {
            Class.forName(driver);
            con = DriverManager.getConnection(url, userName, password);
        } catch (ClassNotFoundException e) {
            logger.error("装载 JDBC/ODBC 驱动程序失败。");
        } catch (SQLException e) {
            logger.error("无法连接数据库");
        }
        return con;
    }

    protected void close(PreparedStatement pstmt, ResultSet rs, Connection conn) {
        try {
            if (null != rs) {
                rs.close();
            }
            if (null != pstmt) {
                pstmt.close();
            }
            if (null != conn) {
                conn.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            try {
                if (null != rs) {
                    rs.close();
                }
                if (null != pstmt) {
                    pstmt.close();
                }
                if (null != conn) {
                    conn.close();
                }
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * 测试数据库连接sql
     * 
     * @return
     */
    public String testConn() {
        String sql = "select 1 from dual ";
        Connection conn = getDBConnection(Const.DBURL, Const.DBUSERNAME,
                Const.DBPASSWORD);
        PreparedStatement pstmt = null;
        ResultSet rs = null;
        try {
            pstmt = conn.prepareStatement(sql);
            rs = pstmt.executeQuery();
            while (rs.next()) {
                System.out.println(rs.getString(1));
            }
            this.close(pstmt, rs, conn);
        } catch (SQLException e) {
            e.printStackTrace();
            return "failure";
        }
        return "success!!!";
    }

    @Test
    public void test() {
        DBHelper_Oracle helper = new DBHelper_Oracle();
        helper.testConn();
    }

}

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;

import org.junit.Test;

public class DbHelper extends DBHelper_Oracle {

    private Connection conn;

    public DbHelper(String url, String userName, String password) {
        this.conn = super.getDBConnection(url, userName, password);
    }

    /**
     * 查询筛选出来的总数
     * 
     * @param status        状态
     *            
     * @param startDate  开始日期
     *            
     * @param endDate    结束日期
     *            
     * @return
     */
    public long getXSLselectCount(String status, String startDate,
            String endDate) {
        String sql = "select count(*) from XXX WHERE STATUS = ?  AND TR_DATE>=to_date( ? , 'yyyy-mm-dd')and TR_DATE<=to_date( ?, 'yyyy-mm-dd')";
        try {
            PreparedStatement pstmt = this.conn.prepareStatement(sql);
            pstmt.setString(1, status);
            pstmt.setString(2, startDate);
            pstmt.setString(3, endDate);
            ResultSet rs = pstmt.executeQuery();
            if (rs.next()) {
                return rs.getLong(1);
            }
            super.close(pstmt, rs, conn);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return 0;
    }

    /**
     * 总条数
     * 
     * @return
     */
    public long getPostionHandoverNums() {
        String sql = "select count(*) from XXX where (HAND_OVER_USER is NOT  NULL) AND (RECEIVE_USER IS NOT NULL)";
        try {
            PreparedStatement pstmt = this.conn.prepareStatement(sql);
            ResultSet rs = pstmt.executeQuery();
            if (rs.next()) {
                return rs.getLong(1);
            }
            super.close(pstmt, rs, conn);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return 0;
    }
}