For example, in the startElement method, this property would contain the actual start-tag that caused the method invocation. Assuming a validating parser, the parsing process merges a document that was originally split across multiple parsed entities into a single entity. Here each callback method in the ContentHandler simply invokes a private method that writes out the current value of the http: A SAX program that echoes the parsed document import org.
Character references will have been resolved. General entity references will probably have been resolved. Attributes that were read in from defaults in the DTD will be explicitly specified. However, the complete information content of the original document should be present, even if the form is different.
The biggest issue with this program is finding a parser that recognizes the http: In my tests, Xerces 1. Node object corresponding to the current SAX event. For example, in the startElement and endElement methods, this property contains an org. Element object representing that element. In the characters method, this property contains the org. Text object which contained the characters from which the text had been read. Comments are the most obvious example. However, this interface is optional.
Parsers are not required to support it. Notice that it is in the org. The LexicalHandler interface package org. An implementation of the LexicalHandler interface import org.
Then it parses the document indicated on the command line. Comments and processing instructions in the DTD, both internal and external subsets, are reported to their respective callback methods, just like comments and processing instructions in the instance document. For instance, parameter entities will have been resolved and only the first declaration of each general entity will be reported.
Nonetheless, the model represented by the entire DTD should be intact. The DeclHandler interface package org. It takes advantage of the fact that all parameter entity references and conditional sections are replaced before the methods of DeclHandler are called. It implements the DeclHandler interface with methods that copy each declaration onto System.
However, because parameter entity references and conditional sections are resolved before these methods are invoked, it outputs a single monolithic DTD. I can see, for example, exactly what the content model for an element such as blockquote really is without having to manually trace the parameter entity references through seven separate modules, and figuring out which modules are likely to be included and which ignored.
A program that prints out a complete DTD import org. There are good and valid reasons to write the original DTD in the form used by the first declaration. Xerces Custom Features Individual parsers generally have a set of their own custom features and properties that control their own special capabilities.
This allows you to configure a parser without having to go outside the standard SAX API, and thus binding your code to one specific parser. Other parsers will have some features similar to these and some unique ones of their own.
However, all will be in a domain of that parser vendor. Validation also depends on the http: The default is true, use the schema if present. However, this is extremely difficult to state, much less implement, in a precisely correct way. Consequently, Xerces by default skips these expensive checks. However, if you want them performed despite their cost you can turn them on by setting this feature to true.
It will not attempt to validate merely well-formed documents that have neither. Nonetheless, this probably indicates a mistake in the DTD.
If the warn-on-duplicate-attdef feature is true, then Xerces should warn of duplicate attribute declarations by invoking the warning method in the registered ErrorHandler. The default is to warn of this problem. Nonetheless, this almost certainly indicates a mistake. If this feature is true, then Xerces will warn of attribute declarations for non-existent elements.
The default is false. This is useful for debugging because it allows you to be informed of and correct multiple errors before parsing a document again. Note that the only thing Xerces will do after it sees the first well-formedness error, is look for more errors.
It will not invoke any methods in any of the callback interfaces except ErrorHandler. The default is true; and if validation is turned on, this feature is automatically turned on and cannot be turned off. The default is true. If validation is turned on, this feature is automatically turned on and cannot be turned off. It uses dynamic validation so it only reports validity errors if the document is in fact trying to be valid. It turns on all optional warnings. And it continues parsing after a fatal error so it can find and report any more errors it spots in the document.
The downside is that it is totally dependent on the Xerces parser. It will not run with any other parser. Indeed it might even have troubles with earlier or later versions of Xerces. I wrote this with 1.
The reference to entity "section" must end with the ';' delimiter. The advantage of using XercesChecker instead of one of the earlier generic checking programs is that XercesChecker gives me a reasonably complete list of all the errors in one pass. While often useful, this can be dangerous. If the order document is invalid, your system rejects it. However, this system has a flaw. For this and other reasons, the schema specification explicitly states that the xsi: The client application parsing a document is allowed to override the schema locations given in the document with schemas of its own choosing.
For this purpose, Xerces has two custom properties: They have the same syntax as the xsi: For instance, this code fragment says that elements not in any namespace should be validated against the schema found at the relative URL orders.
These properties are only available in Xerces. In fact, as I write this Sun has just proposed adding http: For instance, it could be an InputStream or an InputSource object. Other parsers will doubtless implement this in other ways.