edu.harvard.hul.ois.jhove.module

Class XmlModule

java.lang.Object

ModuleBase

edu.harvard.hul.ois.jhove.module.XmlModule

public class XmlModule
extends ModuleBase

Module for identification and validation of XML files.

Author:

Gary McGath

Field Summary

Fields

Modifier and Type	Field and Description
protected String	_baseURL
protected Checksummer	_ckSummer PRIVATE INSTANCE FIELDS.
protected ChecksumInputStream	_cstream
protected DataInputStream	_dstream
protected Map<String,File>	_localSchemas
protected Property	_metadata
protected boolean	_parseFromSig
protected List<Property>	_propList
protected boolean	_sigWantsDecl
protected TextMDMetadata	_textMD
protected boolean	_withTextMD
protected String	_xhtmlDoctype

Constructor Summary

Constructors

Constructor and Description
XmlModule() Instantiate an XmlModule object.

Method Summary

Modifier and Type	Method and Description
void	checkSignatures(File file, InputStream stream, RepInfo info) Check if the digital object conforms to this Module's internal signature information.
protected void	initParse()
protected static String	intTo4DigitHex(int n)
protected static boolean	isNotEmpty(String value) Verification that the string contains something usefull.
protected static boolean	nameInCollection(String name, Collection<String> coll)
void	param(String param) Per-action initialization.
int	parse(InputStream stream, RepInfo info, int parseIndex) Parse the content of a purported XML digital object and store the results in RepInfo.
void	resetParams() Reset parameter settings.
void	setXhtmlDoctype(String doctype) Sets the value of the doctype string, assumed to have been forced to upper case.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

_ckSummer

protected Checksummer _ckSummer

PRIVATE INSTANCE FIELDS.

_cstream

protected ChecksumInputStream _cstream

_dstream

protected DataInputStream _dstream

_propList

protected List<Property> _propList

_metadata

protected Property _metadata

_xhtmlDoctype

protected String _xhtmlDoctype

_baseURL

protected String _baseURL

_sigWantsDecl

protected boolean _sigWantsDecl

_parseFromSig

protected boolean _parseFromSig

_withTextMD

protected boolean _withTextMD

_textMD

protected TextMDMetadata _textMD

_localSchemas

protected Map<String,File> _localSchemas

Constructor Detail

XmlModule

public XmlModule()

Instantiate an XmlModule object.

Method Detail

setXhtmlDoctype

public void setXhtmlDoctype(String doctype)

Sets the value of the doctype string, assumed to have been forced to upper case. This is set only when the HTML module invokes the XML module for an XHTML document.

resetParams

public void resetParams()
                 throws Exception

Reset parameter settings. Returns to a default state without any parameters.

Throws:

Exception

param

public void param(String param)

Per-action initialization.

Parameters:

param - The module parameter; under command-line Jhove, the -p parameter. If the parameter starts with "schema", then the part to the right of the equal sign identifies a URI with a local path (URI, then semicolon, then path). If the first character is 's' and the parameter isn't "schema", then signature checking requires a document declaration, and the rest of the URL is considered as follows. If the parameter begins with 'b' or 'B', then the remainder of the parameter is used as a base URL. Otherwise it is ignored, and there is no base URL.

parse

public int parse(InputStream stream,
                 RepInfo info,
                 int parseIndex)
          throws IOException

Parse the content of a purported XML digital object and store the results in RepInfo. This is designed to be called in two passes. On the first pass, a nonvalidating parse is done. If this succeeds, and the presence of DTD's or schemas is detected, then parse returns 1 so that it will be called again to do a validating parse. If there is nothing to validate, we consider it "valid."

Parameters:

stream - An InputStream, positioned at its beginning, which is generated from the object to be parsed. If multiple calls to parse are made on the basis of a nonzero value being returned, a new InputStream must be provided each time.

info - A fresh (on the first call) RepInfo object which will be modified to reflect the results of the parsing If multiple calls to parse are made on the basis of a nonzero value being returned, the same RepInfo object should be passed with each call.

parseIndex - Must be 0 in first call to parse. If parse returns a nonzero value, it must be called again with parseIndex equal to that return value.

Throws:

IOException

checkSignatures

public void checkSignatures(File file,
                            InputStream stream,
                            RepInfo info)
                     throws IOException

Check if the digital object conforms to this Module's internal signature information. XML is a particularly messy case; in general, there's no even moderately good way to check "signatures" without parsing the whole file, since the document declaration is optional. We provide the user two choices, based on the "s" parameter. If 's' is the first character of the module parameter, then we look for an XML document declaration, and say there's no signature if it's missing. (This can reject well-formed XML files, though not valid ones.) Otherwise, if there's no document declaration, we parse the whole file.

Parameters:

file - A File object for the object being parsed

stream - An InputStream, positioned at its beginning, which is generated from the object to be parsed

info - A fresh RepInfo object which will be modified to reflect the results of the test

Throws:

IOException

initParse

protected void initParse()

nameInCollection

protected static boolean nameInCollection(String name,
                                          Collection<String> coll)

intTo4DigitHex

protected static String intTo4DigitHex(int n)

isNotEmpty

protected static boolean isNotEmpty(String value)

Verification that the string contains something usefull.

Parameters:

value - string to test

Returns:

boolean