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      1 """Different kinds of SAX Exceptions"""
      2 import sys
      3 if sys.platform[:4] == "java":
      4     from java.lang import Exception
      5 del sys
      6 
      7 # ===== SAXEXCEPTION =====
      8 
      9 class SAXException(Exception):
     10     """Encapsulate an XML error or warning. This class can contain
     11     basic error or warning information from either the XML parser or
     12     the application: you can subclass it to provide additional
     13     functionality, or to add localization. Note that although you will
     14     receive a SAXException as the argument to the handlers in the
     15     ErrorHandler interface, you are not actually required to raise
     16     the exception; instead, you can simply read the information in
     17     it."""
     18 
     19     def __init__(self, msg, exception=None):
     20         """Creates an exception. The message is required, but the exception
     21         is optional."""
     22         self._msg = msg
     23         self._exception = exception
     24         Exception.__init__(self, msg)
     25 
     26     def getMessage(self):
     27         "Return a message for this exception."
     28         return self._msg
     29 
     30     def getException(self):
     31         "Return the embedded exception, or None if there was none."
     32         return self._exception
     33 
     34     def __str__(self):
     35         "Create a string representation of the exception."
     36         return self._msg
     37 
     38     def __getitem__(self, ix):
     39         """Avoids weird error messages if someone does exception[ix] by
     40         mistake, since Exception has __getitem__ defined."""
     41         raise AttributeError("__getitem__")
     42 
     43 
     44 # ===== SAXPARSEEXCEPTION =====
     45 
     46 class SAXParseException(SAXException):
     47     """Encapsulate an XML parse error or warning.
     48 
     49     This exception will include information for locating the error in
     50     the original XML document. Note that although the application will
     51     receive a SAXParseException as the argument to the handlers in the
     52     ErrorHandler interface, the application is not actually required
     53     to raise the exception; instead, it can simply read the
     54     information in it and take a different action.
     55 
     56     Since this exception is a subclass of SAXException, it inherits
     57     the ability to wrap another exception."""
     58 
     59     def __init__(self, msg, exception, locator):
     60         "Creates the exception. The exception parameter is allowed to be None."
     61         SAXException.__init__(self, msg, exception)
     62         self._locator = locator
     63 
     64         # We need to cache this stuff at construction time.
     65         # If this exception is raised, the objects through which we must
     66         # traverse to get this information may be deleted by the time
     67         # it gets caught.
     68         self._systemId = self._locator.getSystemId()
     69         self._colnum = self._locator.getColumnNumber()
     70         self._linenum = self._locator.getLineNumber()
     71 
     72     def getColumnNumber(self):
     73         """The column number of the end of the text where the exception
     74         occurred."""
     75         return self._colnum
     76 
     77     def getLineNumber(self):
     78         "The line number of the end of the text where the exception occurred."
     79         return self._linenum
     80 
     81     def getPublicId(self):
     82         "Get the public identifier of the entity where the exception occurred."
     83         return self._locator.getPublicId()
     84 
     85     def getSystemId(self):
     86         "Get the system identifier of the entity where the exception occurred."
     87         return self._systemId
     88 
     89     def __str__(self):
     90         "Create a string representation of the exception."
     91         sysid = self.getSystemId()
     92         if sysid is None:
     93             sysid = "<unknown>"
     94         linenum = self.getLineNumber()
     95         if linenum is None:
     96             linenum = "?"
     97         colnum = self.getColumnNumber()
     98         if colnum is None:
     99             colnum = "?"
    100         return "%s:%s:%s: %s" % (sysid, linenum, colnum, self._msg)
    101 
    102 
    103 # ===== SAXNOTRECOGNIZEDEXCEPTION =====
    104 
    105 class SAXNotRecognizedException(SAXException):
    106     """Exception class for an unrecognized identifier.
    107 
    108     An XMLReader will raise this exception when it is confronted with an
    109     unrecognized feature or property. SAX applications and extensions may
    110     use this class for similar purposes."""
    111 
    112 
    113 # ===== SAXNOTSUPPORTEDEXCEPTION =====
    114 
    115 class SAXNotSupportedException(SAXException):
    116     """Exception class for an unsupported operation.
    117 
    118     An XMLReader will raise this exception when a service it cannot
    119     perform is requested (specifically setting a state or value). SAX
    120     applications and extensions may use this class for similar
    121     purposes."""
    122 
    123 # ===== SAXNOTSUPPORTEDEXCEPTION =====
    124 
    125 class SAXReaderNotAvailable(SAXNotSupportedException):
    126     """Exception class for a missing driver.
    127 
    128     An XMLReader module (driver) should raise this exception when it
    129     is first imported, e.g. when a support module cannot be imported.
    130     It also may be raised during parsing, e.g. if executing an external
    131     program is not permitted."""
    132