JDBC获取结果集与数据库的元数据

连接.getMetaData()获取数据库的元对象
结果集.getMetaData()获取结果集的元对象

import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
/**
 * 结果集的元数据
 *
 * @author Administrator
 *
 */
public class TestResultMetaData {
	public static void main(String[] args) throws SQLException {
		Connection connection = DBUtil.getConnection();
		DatabaseMetaData dm = connection.getMetaData();//获取数据库的元对象
		System.out.println(dm.getDriverVersion());//输出数据库版本
		String sql = "select empno,ename,job,sal,deptno from emp";
		PreparedStatement ps = connection.prepareStatement(sql);
		ResultSet rs = ps.executeQuery();
		// 获得结果集元数据对象
		ResultSetMetaData rsmd = rs.getMetaData();
		// 获得结果集列数
		int count = rsmd.getColumnCount();
		System.out.println(count);
		for (int i = 1; i <= count; i++) {
			System.out.println(rsmd.getColumnName(i) + ":" + rsmd.getColumnTypeName(i));
		}
	}
}