| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| package org.apache.vinci.debug; |
| |
| import java.io.PrintStream; |
| import java.text.DateFormat; |
| import java.util.Date; |
| import java.util.Locale; |
| |
| /** |
| * Miscellaneous debugging functionality such as error logging, assertion checking and exception |
| * reporting. All output produced by this class goes to debugStream which is configurable. This |
| * class is thread safe. |
| * |
| * This is JDK1.3 legacy as this functionality is now provided natively by Java 1.4. |
| */ |
| public class Debug { |
| static private volatile boolean log_messages = true; |
| |
| static private volatile boolean log_exceptions = true; |
| |
| static private boolean output_thread_name = false; |
| |
| static private PrintStream debugStream = System.err; |
| |
| static private DateFormat formatter = DateFormat.getDateTimeInstance(DateFormat.SHORT, |
| DateFormat.SHORT, Locale.ENGLISH); |
| |
| static private Date now = new Date(); |
| |
| /** |
| * This utility class not meant to be instantiated. |
| */ |
| private Debug() { |
| } |
| |
| /** |
| * Set the debugging stream. If no debug stream is explicitly set, then System.err is used. |
| * |
| * @param w |
| * The stream where debug output will be directed. |
| */ |
| synchronized static public void setDebuggingStream(PrintStream w) { |
| debugStream = w; |
| } |
| |
| /** |
| * Get the debugging stream. |
| * |
| * @return The stream currently used for debug output. |
| */ |
| synchronized static public PrintStream getDebuggingStream() { |
| return debugStream; |
| } |
| |
| /** |
| * Set whether debugging messages will be logged to the debug stream. Default is true. |
| * |
| * @param on |
| * Whether or not printed debug messages will go to the log. |
| */ |
| synchronized static public void setLogMessages(boolean on) { |
| log_messages = on; |
| if (on) { |
| Debug.p("vinci.debug.Debug", "Message logging turned ON."); |
| } |
| } |
| |
| /** |
| * Determine if message logging is enabled. |
| * |
| * @return true if message logging is enabled |
| */ |
| synchronized static public boolean getLogMessages() { |
| return log_messages; |
| } |
| |
| /** |
| * Turn on/off the logging of reported exceptions. Default is on. |
| * |
| * @param on |
| * Whtehr or not reported exceptions will be directed to the log. |
| */ |
| synchronized static public void setLogExceptions(boolean on) { |
| log_exceptions = on; |
| Debug.p("vinci.debug.Debug", "Exception logging turned " + ((on) ? "ON" : "OFF")); |
| } |
| |
| /** |
| * Determine if exception logging is enabled. |
| * |
| * @return true if message logging is enabled |
| */ |
| synchronized static public boolean getLogExceptions() { |
| return log_messages; |
| } |
| |
| /** |
| * Turn on/off the reporting of thread name in the debug log. Default is off. |
| * |
| * @param on |
| * Whether or not the thread name will appear in the output. |
| */ |
| synchronized static public void setThreadNameOutput(boolean on) { |
| output_thread_name = on; |
| } |
| |
| /** |
| * Report the exception to the debug log. Usually used to record exceptions that are unexpected, |
| * yet do not indicate fatal conditions (e.g. they are recoverable). |
| * |
| * @param e |
| * The exception to report. |
| * @param message |
| * Additional information to report along with the exception. |
| * |
| * @pre e != null |
| */ |
| synchronized static public void reportException(Throwable e, String message) { |
| if (log_exceptions) { |
| printDebuggingMessage("===================================="); |
| debugStream.println("(WARNING) Unexpected exception: " + message); |
| e.printStackTrace(debugStream); |
| debugStream.flush(); |
| } |
| } |
| |
| /** |
| * Report the Exception (or Throwable) to the debug log. Usually used to record exceptions that |
| * are unexpected, yet do not indicate fatal conditions (e.g. they are recoverable). |
| * |
| * @param e |
| * The exception to report. |
| * |
| * @pre e != null |
| */ |
| synchronized static public void reportException(Throwable e) { |
| if (log_exceptions) { |
| printDebuggingMessage("===================================="); |
| debugStream.println("(WARNING) Unexpected exception: "); |
| e.printStackTrace(debugStream); |
| debugStream.flush(); |
| } |
| } |
| |
| /** |
| * Print the provided message to the debug log (if message logging is on). Does not automatically |
| * flush the message to the log. Call flush() if you need to ensure the message is immediately |
| * flushed. |
| * |
| * @param message |
| * The message to report. |
| * @return The string provided as an argument (to support log chaining). |
| */ |
| synchronized static public String printDebuggingMessage(String message) { |
| if (log_messages) { |
| now.setTime(System.currentTimeMillis()); |
| if (output_thread_name) { |
| debugStream.println("[" + formatter.format(now) + " | " + Thread.currentThread().getName() |
| + "] " + message); |
| } else { |
| debugStream.println("[" + formatter.format(now) + "] " + message); |
| } |
| } |
| return message; |
| } |
| |
| /** |
| * Print the provided message to the debug log (if message logging is on). Does not automatically |
| * flush the message to the log. Call flush() if you need to ensure the message is immediately |
| * flushed. |
| * |
| * @param location |
| * A string indicating which part of code is generating the message. |
| * @param message |
| * The message to log. |
| */ |
| synchronized static public void printDebuggingMessage(String location, String message) { |
| if (log_messages) { |
| now.setTime(System.currentTimeMillis()); |
| if (output_thread_name) { |
| debugStream.println("[" + formatter.format(now) + " | " + Thread.currentThread().getName() |
| + "](" + location + ") " + message); |
| } else { |
| debugStream.println("[" + formatter.format(now) + "](" + location + ") " + message); |
| } |
| } |
| } |
| |
| /** |
| * Same function as {@link #printDebuggingMessage(String)} but easier to type. |
| * @param message - |
| * @return - |
| */ |
| static public String p(String message) { |
| return printDebuggingMessage(message); |
| } |
| |
| /** |
| * Same function as {@link #printDebuggingMessage(String,String)} but easier to type. |
| * @param location - |
| * @param message - |
| */ |
| static public void p(String location, String message) { |
| printDebuggingMessage(location, message); |
| } |
| |
| /** |
| * Check the provided assertion. Used to be named "assert" but renamed to "Assert" to avoid name |
| * conflict with the native JDK 1.4 assert function. |
| * |
| * @param check |
| * The result of the assertion check, which should be false if it fails. |
| * @exception AssertionFailedException |
| * thrown if the method parameter is false. |
| */ |
| static public void Assert(boolean check) throws AssertionFailedException { |
| if (!check) { |
| throw new AssertionFailedException("no message"); |
| } |
| } |
| |
| /** |
| * Check the provided assertion. Used to be named "assert" but renamed to "Assert" to avoid name |
| * conflict with the native JDK 1.4 assert function. |
| * |
| * @param check |
| * Whether or not to throw the exception. |
| * @param message |
| * A message to include in the thrown exception. |
| * @exception AssertionFailedException |
| * thrown if the condition evaluates to false. |
| */ |
| static public void Assert(boolean check, String message) throws AssertionFailedException { |
| if (!check) { |
| throw new AssertionFailedException(message); |
| } |
| } |
| |
| /** |
| * Report a fatal exception to the error stream. This is package protected because the way to |
| * handle fatal errors is to create and throw a FatalException, which takes care of calling this |
| * method for you. |
| * |
| * @param e |
| * The exception which will be logged as a fatal error. |
| */ |
| synchronized static void reportFatalException(Throwable e) { |
| if (log_exceptions) { |
| printDebuggingMessage("===================================="); |
| debugStream.println("(FATAL ERROR) Unexpected exception: "); |
| e.printStackTrace(debugStream); |
| debugStream.flush(); |
| } |
| } |
| |
| /** |
| * Make sure any messages are flushed to the stream. Printing debug messages does not flush the |
| * stream automatically, though reporting exceptions does. |
| */ |
| synchronized static public void flush() { |
| debugStream.flush(); |
| } |
| |
| } // class |