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