DBService.java

1 개요

public class DBService {
	private static DBService instance = null;
	private DBService() {}
	public static DBService getDB() {
		if (instance == null) {
			synchronized (DBService.class) {
				if (instance == null) {
					instance = new DBService();
					instance.init();
				}
			}
		}
		return instance;
	}
	private Connection conn;
	public void init() {
		try {
			Class.forName("org.h2.Driver");
			conn = DriverManager.getConnection("jdbc:h2:~/test","sa","");
		} catch (SQLException e) {  
			e.printStackTrace();
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
	}

3 #

	public Array queryRows(String sql, String... args) {
		try {
			PreparedStatement pstmt = conn.prepareStatement(sql);
			for(int i=0; i<args.length; i++) pstmt.setString(i+1, args[i]);
			ResultSet rs = pstmt.executeQuery();
			ResultSetMetaData md = rs.getMetaData();
			int columns = md.getColumnCount();
			Array rows = new Array();
			while(rs.next()){
				Array row = new Array();
				for(int i=1; i<=columns; ++i) row.put(md.getColumnName(i),rs.getObject(i).toString());
				rows.push(row);
			}
			return rows;
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return null;
	}
	public Array queryRows(String sql) {
		return queryRows(sql, new String[]{});
	}