java基础连接数据库进行查询，java数据库,package cn.o

java基础连接数据库进行查询，java数据库,package cn.o

package cn.outofmemory.snippets.core;import org.apache.commons.dbcp.BasicDataSource;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;public class SimpleBasicDataSource {    public static void main(String[] args) throws Exception {        // Create a BasicDataSource object and configure database         BasicDataSource dataSource = new BasicDataSource();        dataSource.setDriverClassName("com.mysql.jdbc.Driver");        dataSource.setUrl("jdbc:mysql://localhost/testdb");        dataSource.setUsername("root");        dataSource.setPassword("root");        Connection conn = null;        PreparedStatement stmt = null;        try {            // Get connection and execute a simple query            conn = dataSource.getConnection();            stmt = conn.prepareStatement("SELECT * FROM users");            ResultSet rs = stmt.executeQuery();            // Print fetched data            while (rs.next()) {                System.out.println("Username : " + rs.getString("username"));            }        } catch (SQLException e) {            e.printStackTrace();        } finally {            if (stmt != null) {                stmt.close();            }            if (conn != null) {                conn.close();            }        }    }}

输出：

Username : ByronUsername : IliasUsername : NikosUsername : Dimitris