www.gusucode.com > ros 工具箱 matlab源码程序 > ros/+robotics/+ros/+internal/ROSException.m
classdef ROSException < MException
%This class is for internal use only. It may be removed in the future.
%ROSException Custom exception object for Java exceptions
% To avoid exposing (and printing) the whole Java error stack
% when exceptions are thrown, this class encapsulates the exception
% causes and only make them available through custom interface
% functions.
% This ROS exception class can be used similarly to the normal
% MException object, but call addCustomCause() instead of addCause() and
% getCustomReport() instead of getReport().
%
%
% ROSException methods:
% addCustomCause - Add a custom cause to this exception
% getCustomReport - Print a report of all custom causes
% saveCustomStackTrace - Save the stack trace before deletion
%
%
% Example:
%
% % Create an exception
% ex = MException('a:b:c', 'Error 1');
%
% % Create the ROS exception object
% newEx = robotics.ros.internal.ROSException('a:b:c', 'Error 2');
% newEx = newEx.addCustomCause(ex));
%
% % Print out an exception report
% newEx.getCustomReport
% Copyright 2014 The MathWorks, Inc.
properties (Access = ?matlab.unittest.TestCase)
%CustomException - Custom exception object
% This exception object stores all custom causes as normal causes
CustomException;
end
methods
function obj = ROSException(varargin)
%ROSException Constructor
% To properly handle backslashes, escape them in the message
% The message input is fed directly into sprintf,
% backslashes in the message can lead to undesired behavior.
switch(nargin)
case 1
% Called with (message) object input.
validateattributes(varargin{1}, {'message'}, {'nonempty'}, ...
'ROSException', 'message');
case 2
% Called with (id, msg) input
validateattributes(varargin{1}, {'char'}, {'nonempty'}, ...
'ROSException', 'identifier');
validateattributes(varargin{2}, {'char'}, {'nonempty'}, ...
'ROSException', 'msg');
% Escape backslashes to avoid warnings
% on MException creation
varargin{2} = strrep(varargin{2}, '\', '\\');
% If backslashes were doubly escaped, fix that
varargin{2} = strrep(varargin{2}, '\\\\', '\\');
otherwise
% Called with (id, msg, v1, ...) input
validateattributes(varargin{1}, {'char'}, {'nonempty'}, ...
'ROSException', 'identifier');
validateattributes(varargin{2}, {'char'}, {'nonempty'}, ...
'ROSException', 'msg');
% Don't escape backslashes, because the additional
% inputs indicate that message should be interpreted
% as proper input to sprintf
end
obj = obj@MException(varargin{:});
obj.CustomException = obj;
end
function newObj = addCustomCause(obj, cause)
%addCustomCause Add a custom cause to this exception
% This function will not alter the cause list for this
% exception object, but will store all causes in the object
% stored in the CustomException property.
%
% Example:
%
% try
% catch ex
% newEx = robotics.ros.internal.ROSException( ...
% message('robotics:ros:SomeError'));
% throw(newEx.addCustomCause(ex));
% end
if ~isa(cause, 'MException')
return;
end
if ~isa(cause, 'robotics.ros.internal.ROSException')
obj.CustomException = obj.CustomException.addCause(cause);
else
obj.CustomException = obj.CustomException.addCause(cause.CustomException);
end
newObj = obj;
end
function newObj = saveCustomStackTrace(obj)
%saveCustomStackTrace Save the stack trace before deletion
% To avoid the stack deletion when using the throwAsCaller
% syntax, use this function to save the stack trace
% internally.
%
% Example:
%
% try
% catch ex
% ex = saveCustomStackTrace(ex);
% throwAsCaller(ex);
% end
%
% ...
%
% ex = MException.last;
% if isa(ex, 'robotics.ros.internal.ROSException')
% % Print out full stack trace and list of causes
% ex.getCustomReport;
% else
% ex.getReport;
% end
causes = obj.CustomException.cause;
obj.CustomException = obj;
if ~isempty(causes)
for c = causes
obj.CustomException = obj.CustomException.addCause(c{1});
end
end
newObj = obj;
end
function rep = getReport(obj, type, key, val)
%getReport - Overloaded function from MException
% Handle special case to avoid infinite recursion for
% CustomException objects that are ROSExceptions themselves
if exist('type', 'var')
if strcmp(type, 'custom')
rep = getReport@MException(obj);
return;
end
end
if strcmp(obj.logLevel, 'none')
% Call the standard getReport function in normal mode
switch nargin
case 1
rep = getReport@MException(obj);
case 2
rep = getReport@MException(obj, type);
otherwise
rep = getReport@MException(obj, type, key, val);
end
else
% Retrieve the custom report in verbose mode
rep = obj.getCustomReport;
end
end
function rep = getCustomReport(obj)
%getCustomReport - Print a report of all custom causes
% This is simply getting a standard report from the CustomEx
% exception.
%
% Example:
% ex = MException.last;
% if isa(ex, 'robotics.ros.internal.ROSException')
% ex.getCustomReport;
% else
% ex.getReport;
% end
if isa(obj.CustomException, 'robotics.ros.internal.ROSException')
rep = obj.CustomException.getReport('custom');
else
rep = obj.CustomException.getReport;
end
end
end
methods (Static)
function rosex = fromException(ex)
%fromException Construct ROSException from other exception
% The input EX can either be a generic MException or a
% ROSException already. All other inputs are invalid. The
% newly created ROSException is returned in ROSEX.
if isa(ex, 'robotics.ros.internal.ROSException')
rosex = saveCustomStackTrace(ex);
return;
elseif isa(ex, 'MException')
rosex = robotics.ros.internal.ROSException(ex.identifier, ex.message);
rosex.CustomException = ex;
return;
else
error(message('robotics:ros:common:WrongInput'));
end
end
end
methods (Static, Access = private)
function newLevel = logLevel(level)
%logLevel Set the log level (verbosity) for ROS exceptions
% The default log level is 'none' and all errors encountered
% through the informal interface have no stack trace or
% causes. Setting the log level to 'all' displays all error
% information for debugging purposes, e.g. in testing.
%
% NEWLEVEL = robotics.ros.internal.ROSException.logLevel('LEVEL') sets
% the ROSException log level to LEVEL, where LEVEL can be
% either 'none' or 'all'. If successful, the new log level is
% returned in NEWLEVEL.
persistent currentLogLevel
mlock
if isempty(currentLogLevel)
currentLogLevel = 'none';
end
% Return current log level if no input
if nargin == 0
newLevel = currentLogLevel;
return;
end
% Valid log level strings
% 'none' is the default log level that is appropriate for most
% users; 'all' is the verbose log level for testing
validLevels = {'all', 'none'};
if ischar(level)
if any(strcmpi(level,validLevels))
currentLogLevel = level;
newLevel = currentLogLevel;
end
end
end
end
methods(Static)
function enableVerboseLogging(enable)
%enableVerboseLogging Enable verbose output for ROS exceptions
% This is the public interface for enabling verbose exception
% output for the informal interface.
%
% robotics.ros.internal.ROSException.enableVerboseLogging(ENABLE)
% enables (ENABLE == true) or disables (ENABLE == false) the
% verbose error output.
validateattributes(enable, {'logical'}, {'nonempty'}, ...
'ROSException', 'enable');
if enable
robotics.ros.internal.ROSException.logLevel('all');
else
robotics.ros.internal.ROSException.logLevel('none');
end
end
end
end