jdbcclient.java

来自「这个是内存数据库的客户端」· Java 代码 · 共 1,234 行 · 第 1/3 页

			// we want nice table views
			e.setProperty(SQLExporter.TYPE_OUTPUT, SQLExporter.VALUE_TABLE);
		}
		e.useSchemas(false);

		try {
			// use the given file for reading
			boolean hasFile = copts.getOption("file").isPresent();
			boolean doEcho = hasFile && copts.getOption("echo").isPresent();
			if (hasFile) {
				String tmp = copts.getOption("file").getArgument();
				int batchSize = 0;
				try {
					in = getReader(tmp);
				} catch (Exception e) {
					System.err.println("Error: " + e.getMessage());
					System.exit(-1);
				}

				// check for batch mode
				oc = copts.getOption("Xbatching");
				if (oc.isPresent()) {
					if (oc.getArgumentCount() == 1) {
						// parse the number
						try {
							batchSize = Integer.parseInt(oc.getArgument());
						} catch (NumberFormatException ex) {
							// complain to the user
							throw new IllegalArgumentException("Illegal argument for Xbatching: " + oc.getArgument() + " is not a parseable number!");
						}
					}
					processBatch(batchSize);
				} else {
					processInteractive(true, doEcho, scolonterm, user);
				}
			} else {
				if (!copts.getOption("quiet").isPresent()) {
					// print welcome message
					out.println("Welcome to the MonetDB interactive JDBC terminal!");
					if (dbmd != null) {
						out.println("Database: " + dbmd.getDatabaseProductName() + " " +
							dbmd.getDatabaseProductVersion());
						out.println("Driver: " + dbmd.getDriverName() + " " +
							dbmd.getDriverVersion());
					}
					out.println("Type \\q to quit, \\h for a list of available commands");
					out.flush();
				}
				processInteractive(false, doEcho, scolonterm, user);
			}

			// free resources, close the statement
			stmt.close();
			// close the connection with the database
			con.close();
			// close the file (if we used a file)
			in.close();
		} catch (Exception e) {
			System.err.println("A fatal exception occurred: " + e.toString());
			e.printStackTrace(System.err);
			// at least try to close the connection properly, since it will
			// close all statements associated with it
			try {
				con.close();
			} catch (SQLException ex) {
				// ok... nice try
			}
			System.exit(-1);
		}
	}

	/**
	 * Tries to interpret the given String as URL or file.  Returns the
	 * assigned BufferedReader, or throws an Exception if the given
	 * string couldn't be identified as a valid URL or file.
	 *
	 * @param uri URL or filename as String
	 * @return a BufferedReader for the uri
	 * @throws Exception if uri cannot be identified as a valid URL or
	 *         file
	 */
	static BufferedReader getReader(String uri) throws Exception {
		BufferedReader ret = null;
		URL u = null;

		// Try and parse as URL first
		try {
			u = new URL(uri);
		} catch (MalformedURLException e) {
			// no URL, try as file
			try {
				ret = new BufferedReader(new FileReader(uri));
			} catch (FileNotFoundException fnfe) {
				// the message is descriptive enough, adds "(No such file
				// or directory)" itself.
				throw new Exception(fnfe.getMessage());
			}
		}

		if (ret == null) try {
			HttpURLConnection.setFollowRedirects(true);
			HttpURLConnection con =
				(HttpURLConnection)u.openConnection();
			con.setRequestMethod("GET");
			String ct = con.getContentType();
			if ("application/x-gzip".equals(ct)) {
				// open gzip stream
				ret = new BufferedReader(new InputStreamReader(
							new GZIPInputStream(con.getInputStream())));
			} else {
				// text/plain otherwise just attempt to read as is
				ret = new BufferedReader(new InputStreamReader(
							con.getInputStream()));
			}
		} catch (IOException e) {
			// failed to open the url
			throw new Exception("No such host: " + e.getMessage());
		} catch (Exception e) {
			// this is an exception that comes from deep ...
			throw new Exception("Invalid URL: " + e.getMessage());
		}

		return(ret);
	}

	/**
	 * Starts an interactive processing loop, where output is adjusted to an
	 * user session.  This processing loop is not suitable for bulk processing
	 * as in executing the contents of a file, since processing on the given
	 * input is done after each row that has been entered.
	 *
	 * @param hasFile a boolean indicating whether a file is used as input
	 * @param doEcho a boolean indicating whether to echo the given input
	 * @param user a String representing the username of the current user
	 * @throws IOException if an IO exception occurs
	 * @throws SQLException if a database related error occurs
	 */
	public static void processInteractive(
		boolean hasFile,
		boolean doEcho,
		boolean scolonterm,
		String user
	)
		throws IOException, SQLException
	{
		// an SQL stack keeps track of ( " and '
		SQLStack stack = new SQLStack();
		// a query part is a line of an SQL query
		QueryPart qp = null;

		String query = "", curLine;
		StringBuffer rl = new StringBuffer();
		boolean wasComplete = true, doProcess, lastac = false;
		if (!hasFile) {
			lastac = con.getAutoCommit();
			out.println("auto commit mode: " + (lastac ? "on" : "off"));
			out.print(getPrompt(user, stack, true));
			out.flush();
		}

		// the main (interactive) process loop
		int i = 0;
		char c = 0;
		for (i = 1; true; i++) {
			// Manually read a line, because we want to detect an EOF
			// (ctrl-D).  Doing so allows to have a terminator for query
			// which is not based on a special character, as is the
			// problem for XQuery
			curLine = in.readLine();
			if (curLine == null) {
				out.println("");
				if (query != "") {
					try {
						executeQuery(query, stmt, out);
					} catch (SQLException e) {
						out.flush();
						if (hasFile) {
							System.err.println("Error on line " + i + ": " + e.getMessage());
						} else {
							System.err.println("Error: " + e.getMessage());
						}
						// print all error messages in the chain (if any)
						while ((e = e.getNextException()) != null) {
							System.err.println(e.getMessage());
						}
					}
					query = "";
					wasComplete = true;
					if (!hasFile) {
						boolean ac = con.getAutoCommit();
						if (ac != lastac) {
							out.println("auto commit mode: " + (ac ? "on" : "off"));
							lastac = ac;
						}
						out.print(getPrompt(user, stack, wasComplete));
					}
					out.flush();
					// try to read again
					continue;
				} else {
					// user did ctrl-D without something in the buffer,
					// so terminate
					break;
				}
			}

			if (doEcho) {
				out.println(curLine);
				out.flush();
			}
			qp = scanQuery(curLine, stack, scolonterm);
			if (!qp.isEmpty()) {
				doProcess = true;
				if (wasComplete) {
					doProcess = false;
					// check for commands only when the previous row was
					// complete
					if (qp.getQuery().equals("\\q")) {
						// quit
						break;
					} else if (qp.getQuery().startsWith("\\h")) {
						out.println("Available commands:");
						out.println("\\q      quits this program");
						out.println("\\h      this help screen");
						if (dbmd != null)
							out.println("\\d      list available tables and views");
						out.println("\\d<obj> describes the given table or view");
						out.println("\\l<uri> executes the contents of the given file or URL");
						out.println("\\i<uri> batch executes the inserts from the given file or URL");
					} else if (dbmd != null && qp.getQuery().startsWith("\\d")) {
						try {
							String object = qp.getQuery().substring(2).trim().toLowerCase();
							if (scolonterm && object.endsWith(";"))
								object = object.substring(0, object.length() - 1);
							if (!object.equals("")) {
								int dot;
								String schema;

								if ((dot = object.indexOf(".")) != -1) {
									// use provided schema
									schema = object.substring(0, dot);
									object = object.substring(dot + 1);
								} else {
									// get current schema
									ResultSet rs = stmt.executeQuery("SELECT current_schema");
									if (!rs.next())
										throw new SQLException("current schema unknown!");
									schema = rs.getString(1);
									rs.close();
								}
								ResultSet tbl = dbmd.getTables(
										null, schema, null, null);

								// we have an object, see if we can find it
								boolean found = false;
								while (tbl.next()) {
									if (tbl.getString("TABLE_NAME").equalsIgnoreCase(object) ||
											(tbl.getString("TABLE_SCHEM") + "." + tbl.getString("TABLE_NAME")).equalsIgnoreCase(object)) {
										// we found it, describe it
										e.dumpSchema(
												dbmd,
												tbl.getString("TABLE_TYPE"),
												tbl.getString("TABLE_CAT"),
												tbl.getString("TABLE_SCHEM"),
												tbl.getString("TABLE_NAME")
												);

										found = true;
										break;
											}
								}
								if (!found) System.err.println("Unknown table or view: " + object);
								tbl.close();
							} else {
								String[] types = {"TABLE", "VIEW"};
								// get current schema
								ResultSet rs = stmt.executeQuery("SELECT current_schema");
								if (!rs.next())
									throw new SQLException("current schema unknown!");
								ResultSet tbl = dbmd.getTables(
										null, rs.getString(1), null, types);
								rs.close();

								// give us a list with tables
								while (tbl.next()) {
									out.println(tbl.getString("TABLE_TYPE") + "\t" +
											tbl.getString("TABLE_SCHEM") + "." +
											tbl.getString("TABLE_NAME"));
								}
								tbl.close();
							}
						} catch (SQLException e) {
							out.flush();
							System.err.println("Error: " + e.getMessage());
						}
					} else if (qp.getQuery().startsWith("\\l") ||
							qp.getQuery().startsWith("\\i"))
					{
						String object = qp.getQuery().substring(2).trim();
						if (scolonterm && object.endsWith(";"))
							object = object.substring(0, object.length() - 1);
						if (object.equals("")) {
							System.err.println("Usage: '" + qp.getQuery().substring(0, 2) + "<uri>' where <uri> is a file or URL");
						} else {
							// temporarily redirect input from in
							BufferedReader console = in;
							try {
								in = getReader(object);
								if (qp.getQuery().startsWith("\\l")) {
									processInteractive(
										true, doEcho, scolonterm, user);
								} else {
									processBatch(0);
								}
							} catch (Exception e) {
								out.flush();
								System.err.println("Error: " + e.getMessage());
							} finally {
								// put back in redirection
								in = console;
							}
						}
					} else {
						doProcess = true;
					}
				}

				if (doProcess) {
					query += qp.getQuery() + (qp.hasOpenQuote() ? "\\n" : " ");
					if (qp.isComplete()) {
						// strip off trailing ';'
						query = query.substring(0, query.length() - 2);
						// execute query
						try {
							executeQuery(query, stmt, out);
						} catch (SQLException e) {
							out.flush();
							if (hasFile) {
								System.err.println("Error on line " + i + ": " + e.getMessage());
							} else {
								System.err.println("Error: " + e.getMessage());
							}
						}
						query = "";
						wasComplete = true;
					} else {
						wasComplete = false;
					}
				}
			}
			if (!hasFile) {
				boolean ac = con.getAutoCommit();
				if (ac != lastac) {
					out.println("auto commit mode: " + (ac ? "on" : "off"));
					lastac = ac;
				}
				out.print(getPrompt(user, stack, wasComplete));
			}
			out.flush();
		}
	}

	/**
	 * Executes the given query and prints the result tabularised to the
	 * given PrintWriter stream.  The result of this method is the
	 * default output of a query: tabular data.
	 *
	 * @param query the query to execute
	 * @param stmt the Statement to execute the query on
	 * @param out the PrintWriter to write to
	 * @throws SQLException if a database related error occurs
	 */
	private static void executeQuery(String query,
			Statement stmt,
			PrintWriter out)
		throws SQLException
	{
		// warnings generated during querying
		SQLWarning warn;

		// execute the query, let the driver decide what type it is
		int aff = -1;
		boolean	nextRslt = stmt.execute(query);
		if (!nextRslt) aff = stmt.getUpdateCount();
		do {
			if (nextRslt) {
				// we have a ResultSet, print it
				ResultSet rs = stmt.getResultSet();

				e.dumpResultSet(rs);

				// if there were warnings for this result,
				// show them!
				warn = rs.getWarnings();
				if (warn != null) {
					// force stdout to be written so the
					// warning appears below it
					out.flush();
					do {
						System.err.println("ResultSet warning: " +
							warn.getMessage());
						warn = warn.getNextWarning();
					} while (warn != null);
					rs.clearWarnings();
				}
				rs.close();
			} else if (aff != -1) {
				if (aff == Statement.SUCCESS_NO_INFO) {
					out.println("Operation successful");
				} else {
					// we have an update count
					out.println(aff + " affected row" + (aff != 1 ? "s" : ""));