db.java

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package nm;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.Statement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class DB {

	Connection connection = null;

	ResultSet rs = null;

	Statement statement = null;

	public DB(DataSource dataSource) {

		try {
			connection = dataSource.getConnection();
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

	public DB(Connection connection) {
		this.connection = connection;
	}

	public ResultSet OpenSql(String sql) {
		try {
			statement = connection.createStatement(
					ResultSet.TYPE_SCROLL_INSENSITIVE,
					ResultSet.CONCUR_READ_ONLY);
			rs = statement.executeQuery(sql);
		} catch (SQLException ex) {
			ex.printStackTrace();
		}
		return rs;
	}

	public int ExecSql(String sql) {
		int result = 0;
		try {
			statement = connection.createStatement();
			result = statement.executeUpdate(sql);
		} catch (SQLException ex) {
			System.err.println(ex.getMessage());

		}
		return result;
	}

	public void close() {
		if (connection != null) {
			try {
				if (rs != null) {
					rs.close();
					rs = null;
				}
				if (statement != null) {
					statement.close();
					statement = null;
				}
				if (connection != null) {
					connection.close();
					connection = null;
				}
			} catch (SQLException ex) {
				System.err.println(ex.getMessage());
			}
		}
	}
}