XMLDocument must support parsing of DTD elements, attributes, entities

[angelozerr]

This issue is very important of we wish to support DTD (I mean not validation, completion based on DTD inside XML, but I mean DTD content):

• completion (ex : <! +ctrl +space provides <!ELEMENT, <!ATTRIBUTE, etc) -> (see Completion for DTD <!ELEMENT, <!ATTRIBUTE,  #232)
• outline (for internal DTD inside XML and external DTD) -> document symbol provider (see Outline for DTD file is messed up #226)
• hyperlink between elements -> (see Add support for textDocument/definition for DTD #233)
• references between elements -> (see Add support for textDocument/references for DTD #234)
• adjust DTD errors for DTD content -> (see Adjust range error for internal DTD declaration #225)
• formatting of DTD elements, attributes, entities -> (see DTD elements are not formatted #221)

@NikolasKomonen do you know when you could provide a PR for this issue? I need it for adjust DTD error. Thanks!

[angelozerr]

@NikolasKomonen for your work with DTD parser, I suggest you read https://www.w3.org/TR/REC-xml/#dt-doctype to use the well name.

For instance you have defined a custom DocumentType#getInternalDTD but it's the same thing than org.w3c.dom.DocumentType#getInternalSubset().

Other idea is prefering to store start/end offset instead of storing the string in the DocumentType. You can see a sample with DocumentType#getContent. It gives you 2 benefits:

• you have location offset of content. So for instance for systemId, it's better to have start/end offset of systemId which will gives the capability to manage completion for DTD files, hyperlink, etc. You have a sample in NoNamespaceSchemaLocation. Instead of storing the "xsi:noNamespaceShcemaLocation" attribute value, I store the attribute (in other words the start/end offset of the attribute value) and after I can manage hyperlink (see ContentModelDocumentLinkParticipant)

• it avoids to call substring (from start/end offset retrieved by the scanner) to get the text although you don't need the string value. The string value must b egetted only if you need it (ex: if user do an hyperlink).

Hope you will understand what I mean.

[angelozerr]

@NikolasKomonen pay attention I have done a big refactoring to rename DOM structures (ex: Attr to DOMAttr). I have done that since suggestion of sonar.

[angelozerr]

Scanner and parser supports now DTD tolerant parsing. I close this issue. If you find bugs, please create a new issue.