jdbctemplatequery.java

Spring2.0宝典

package lee;

import java.util.List;
import java.util.Iterator;

import javax.sql.DataSource;
import com.mchange.v2.c3p0.ComboPooledDataSource;

import org.springframework.jdbc.core.JdbcTemplate;

import java.util.Map;

/**
 * @author  yeeku.H.lee [e-mail]
 * @version  1.0
 * <br>Copyright (C), 2005-2008, yeeku.H.Lee
 * <br>This program is protected by copyright laws.
 * <br>Program Name:
 * <br>Date: 
 */

public class JdbcTemplateQuery
{
	
	public static void main(String[] args)throws Exception
	{

		ComboPooledDataSource ds = new ComboPooledDataSource();
		ds.setDriverClass("com.mysql.jdbc.Driver");
		ds.setJdbcUrl("jdbc:mysql://localhost:3306/j2ee");
		ds.setUser("root");
		ds.setPassword("32147");
        ds.setMaxPoolSize(40);
        ds.setMinPoolSize(2); 
        ds.setMaxStatements(180); 
		
		//创建一个JdbcTemplate
		JdbcTemplate jt = new JdbcTemplate();
		//为JdbcTemplate指定DataSource
		jt.setDataSource(ds);
		//如果只需返回一个特定值,可直接查询
		int count = jt.queryForInt("select count(*) from mytable");
		System.out.println(count);
        //此处的转换实际非常简单：只支持Varchar->String的转换。
		String nametmp = (String)jt.queryForObject("select name from mytable where name='wawa2'",String.class);
		System.out.println(nametmp);

        
		List namelist = jt.queryForList("select name from mytable");

		for (Iterator it = namelist.iterator();it.hasNext(); )
		{
			System.out.println(it.next().getClass());           
        }

		//返回系列值
		List list = jt.queryForList("select * from mytable");

		for (Iterator it = list.iterator();it.hasNext(); )
		{
			System.out.println(it.next().getClass());
            System.out.println((Map)it.next());
		}
	}
}