DBUtils结果集处理

1、BeanHandler查询

package jdbc;

import java.sql.Connection;
import java.sql.SQLException;

import org.apache.commons.dbutils.DbUtils;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;

/**
 * <p>
 * Description:BeanHandler处理结果集演示
 * </p>
 * 
 * @author Administrator
 * @date 2018年11月5日下午5:04:55
 */
public class BeanHandlerDemo {

    public static void main(String[] args) throws SQLException {
        // 创建sql语句执行对象
        QueryRunner qr = new QueryRunner();
        // sql语句
        String sql = "select * from sort";
        Object[] params = {};
        // 获得连接
        Connection conn = JDBCUtils.getConnection();
        // 执行sql语句
        Sort sort = qr.query(conn, sql, new BeanHandler<Sort>(Sort.class), params);
        // 打印结果集
        System.out.println(sort);
        // 关闭资源
        DbUtils.closeQuietly(conn);
    }

}

2、BeanListHandler查询

package jdbc;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanListHandler;

/**
 * <p> Description:BeanListHandler类处理结果集演示</p>
 * @author Administrator
 * @date 2018年11月5日下午5:11:32
 */
public class BeanListHandlerDemo {

    public static void main(String[] args) throws SQLException {
        // 创建sql语句执行对象
        QueryRunner qr = new QueryRunner();
        // sql语句
        String sql = "select * from sort";
        Object[] params = {};
        // 获得连接
        Connection conn = JDBCUtils.getConnection();
        // 执行sql语句
        List<Sort> list = qr.query(conn, sql, new BeanListHandler<Sort>(Sort.class), params);
        // 结果集处理
        for (Sort s: list) {
            System.out.println(s);
        }
    }

}

3、ColumeListHandler查询

package jdbc;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.ColumnListHandler;

/**
 * <p>Description:ColumeListHandler类查询演示 </p>
 * @author Administrator
 * @date 2018年11月5日下午5:16:17
 */
public class ColumnListHandlerDemo {

    public static void main(String[] args) throws SQLException {
        // 创建sql语句执行对象
        QueryRunner qr = new QueryRunner();
        // sql语句
        String sql = "select * from sort";
        Object[] params = {};
        // 获得连接
        Connection conn = JDBCUtils.getConnection();
        // 执行sql语句
        List<Object> list = qr.query(conn, sql, new ColumnListHandler<Object>(), params);
        // 处理结果集
        for (Object s: list) {
            System.out.println(s);
        }
    }

}

4、ScalarHandler查询

package jdbc;

import java.sql.Connection;
import java.sql.SQLException;

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.ScalarHandler;
/**
 * <p>Description:ScalarHandler类查询演示 </p>
 * @author Administrator
 * @date 2018年11月5日下午5:23:49
 */
public class ScalarHandlerDemo {

    public static void main(String[] args) throws SQLException {
        // 创建sql语句执行对象
        QueryRunner qr = new QueryRunner();
        // sql语句
        String sql = "select count(*) from sort";
        Object[] params = {};
        // 获得连接
        Connection conn = JDBCUtils.getConnection();
        // 执行sql语句
        Long l = qr.query(conn, sql, new ScalarHandler<Long>(), params);
        // 处理结果集
        System.out.println(l);
    }

}

5、MapHandler查询

package jdbc;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.Map;

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.MapHandler;
/**
 * <p>Description:MapHandler处理结果集演示 </p>
 * @author Administrator
 * @date 2018年11月5日下午5:28:31
 */
public class MapHandlerDemo {

    public static void main(String[] args) throws SQLException {
        // 创建sql语句执行对象
        QueryRunner qr = new QueryRunner();
        // sql语句
        String sql = "select * from sort";
        // 获得连接
        Connection conn = JDBCUtils.getConnection();
        // 执行sql语句
        Map<String, Object> map = qr.query(conn, sql, new MapHandler());
        // 处理结果集
        for (String key: map.keySet()) {
            System.out.println(key + "..." + map.get(key));
        }
    }

}

6、MapListHandler查询

package jdbc;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.MapListHandler;
/**
 * <p>Description:MapListHandler处理结果集演示 </p>
 * @author Administrator
 * @date 2018年11月5日下午5:35:22
 */
public class MapListHandlerDemo {

    public static void main(String[] args) throws SQLException {
        // 创建sql语句执行对象
        QueryRunner qr = new QueryRunner();
        // sql语句
        String sql = "select * from sort";
        // 获得连接
        Connection conn = JDBCUtils.getConnection();
        // 执行sql语句
        List<Map<String, Object>> list = qr.query(conn, sql, new MapListHandler());
        // 处理结果集
        for (Map<String, Object> map : list) {
            for (String key : map.keySet()) {
                // 打印一条记录
                System.out.print(key + "..." + map.get(key));
            }
            // 换行
            System.out.println();
        }

    }

}