javaweb-dbutils2

package cn.itcast.demo;

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

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.ArrayHandler;
import org.apache.commons.dbutils.handlers.ArrayListHandler;
import org.apache.commons.dbutils.handlers.ColumnListHandler;
import org.apache.commons.dbutils.handlers.KeyedHandler;
import org.apache.commons.dbutils.handlers.MapHandler;
import org.apache.commons.dbutils.handlers.MapListHandler;
import org.apache.commons.dbutils.handlers.ScalarHandler;
import org.junit.Test;

import cn.itcast.utils.JdbcUtils;

public class Demo2 {


//测试dbutils各种类型的处理器

/*
create database day17; use day17;

create table user( id int primary key auto_increment, name varchar(40),
password varchar(40), email varchar(60), birthday date );


insert into user(name,password,email,birthday)values('zs','123456','zs@sina.com','1980-09-09');
insert into user(name,password,email,birthday) values('lisi','123456','lisi@sina.com','1980-09-09');
insert into user(name,password,email,birthday) values('wangwu','123456','wangwu@sina.com','1980-09-09');

*/

@Test
public void testArrayHandler() throws SQLException{

QueryRunner qr = new QueryRunner(JdbcUtils.getDataSource());
String sql = "select * from user";
Object result[] = (Object[]) qr.query(sql, new ArrayHandler());
System.out.println(Arrays.asList(result)); //list toString()
}

@Test
public void testArrayListHandler() throws SQLException{

QueryRunner qr = new QueryRunner(JdbcUtils.getDataSource());
String sql = "select * from user";
List<Object[]> list = (List) qr.query(sql, new ArrayListHandler());
for(Object[] o : list){
System.out.println(Arrays.asList(o));
}
}

@Test
public void testColumnListHandler() throws SQLException{
QueryRunner qr = new QueryRunner(JdbcUtils.getDataSource());
String sql = "select * from user";

List list = (List) qr.query(sql, new ColumnListHandler("id"));
System.out.println(list);
}

@Test
public void testKeyedHandler() throws Exception{
QueryRunner qr = new QueryRunner(JdbcUtils.getDataSource());
String sql = "select * from user";

Map<Integer,Map> map = (Map) qr.query(sql, new KeyedHandler("id"));
for(Map.Entry<Integer, Map> me : map.entrySet()){
int id = me.getKey();
Map<String,Object> innermap = me.getValue();
for(Map.Entry<String, Object> innerme : innermap.entrySet()){
String columnName = innerme.getKey();
Object value = innerme.getValue();
System.out.println(columnName + "=" + value);
}
System.out.println("----------------");
}
}

@Test
public void testMapHandler() throws SQLException{

QueryRunner qr = new QueryRunner(JdbcUtils.getDataSource());
String sql = "select * from user";

Map<String,Object> map = (Map) qr.query(sql, new MapHandler());
for(Map.Entry<String, Object> me : map.entrySet())
{
System.out.println(me.getKey() + "=" + me.getValue());
}
}


@Test
public void testMapListHandler() throws SQLException{
QueryRunner qr = new QueryRunner(JdbcUtils.getDataSource());
String sql = "select * from user";
List<Map> list = (List) qr.query(sql, new MapListHandler());
for(Map<String,Object> map :list){
for(Map.Entry<String, Object> me : map.entrySet())
{
System.out.println(me.getKey() + "=" + me.getValue());
}
}
}

//java.lang.ClassCastException: java.lang.Long
@Test
public void testScalarHandler() throws SQLException{
QueryRunner qr = new QueryRunner(JdbcUtils.getDataSource());
String sql = "select count(*) from user"; //[13] list[13]
/*long l = (Long) qr.query(sql, new ScalarHandler(1));
int count = (int) l;*/

//int count = Integer.parseInt(qr.query(sql, new ScalarHandler(1)).toString());

int count = ((Long)qr.query(sql, new ScalarHandler(1))).intValue();
System.out.println(count);
}

}