This page is historical "for information only" - there is no Apache
release of Eyeball and the code has not been updated for Jena3.
The original source code is available.
This document describes Eyeball, an "RDF lint". See the release notes for descriptions of changes from previous versions. Eyeball was a part of the Jena family of RDF/OWL tools.
Throughout this document, the prefix eye:
stands for the URL
http://jena.hpl.hp.com/Eyeball\#
.
Eyeball is a library and command-line tool for checking RDF and OWL models for various common problems. These problems often result in technically correct but implausible RDF. Eyeball checks against user-provided schema files and makes various closed-world assumptions.
Eyeball can check for:
Eyeball's checks are performed by Inspector plug-ins and can be customised by the user. Rendering its reports to output is performed by Renderer plug-ins which can also be customised by the user.
Fetch the Eyeball distribution zipfile and unpack it somewhere convenient. Eyeball 2.1 comes with its own copy of Jena 2.5 with CVS updates. Do not attempt to use other versions of Jena with Eyeball.
In the Eyeball distribution directory, run the Eyeball tests:
ant test
If these tests fail, something is wrong. Please ask on the user mailing list or file a Jira issue.
If the tests have passed, you can use Eyeball from the installation directory, or copy lib, etc and mirror to somewhere convenient.
You must ensure that all the Eyeball jars from lib are on your classpath. (Note that Eyeball comes with its own Jena jar files and may not work with other Jena jars.) The directories etc and mirror should be in the current directory or also on your classpath.
Run the Eyeball command:
java [java options eg classpath and proxy] jena.eyeball (-check | -sign | -accept) specialURL+ [-assume Reference*] [-config fileOrURL*] [-set Setting*] [-root rootURI] [-render Name] [-include shortName*] [-exclude shortName*] [-analyse | -repair] [-remark] [-version]
The -whatever sections can come in any order and may be repeated, in which case the additional arguments are appended to the existing ones. Exactly one of -check, -sign, -accept, or version must be provided; all the other options are optional.
When Eyeball resolves ordinary filenames or URLs it uses the Jena
file manager to possibly map those names (eg to redirect an
http:
URL to a local cached copy). See the
file manager howto
for details on how to configure the file manager.
java jena.eyeball -version java jena.eyeball -check myDataFile.rdf java jena.eyeball -assume dc -check http://example.com/nosuch.n3 java jena.eyeball -assume mySchema.rdf -check myData.rdf -render xml java jena.eyeball -check myData.rdf -include consistent-type java jena.eyeball -check myConfig.ttl -sign >signedConfig.ttl
The -check command checks the specified models for problems. The
specialURLs designate the models to be checked. In the simplest
case, these are plain filenames, file:
URLs, or http:
URLs. At
least one specialURL must be specified. Each specified model is
checked independently of the others.
-check myModel.ttl -check file:///c:/rdf/pizza.owl -check http://example.com/rdf/beer.rdf
If the specialURL is of the form ont:NAME:base, then the
checked model is the model base treated as an OntModel with the
specification OntModelSpec.<i>NAME</i>
; see
the Jena ontology documentation
for the available names.
-check ont:OWL_MEM_RDFS_INF:myModel.ttl -check ont:OWL_DL_MEM_RULE_INF:http://example.com/rdf/beer.rdf
If the specialURL is of the form ja:R@AF, then the model is that described by the resource R in the Jena assembler description file AF. R is prefix-expanded using the prefixes in AF.
-check ja:my:root@my-assembly.ttl -check ont:OWL_MEM_RDFS_INF:my:root@my-assembly.ttl
If the URL (or the base) is of the form jdbc:DB:head:model, then the checked model is the one called model in the database with connection jdbc:DB:head. (The database user and password must be specified independently using the jena.db.user and jena.db.password system properties.)
-check jdbc:mysql://localhost/test:example
The -config fileOrURL options specify the Eyeball assembler configuration files to load. A single configuration model is constructed as the union of the contents of those files. If this option is omitted, the default configuration file etc/eyeball-config.n3 is loaded. See inside the Eyeball configuration file for details of the configuration file.
-config my-hacked-config-file.n3 -config etc/eyeball-config.n3 extras.ttl
The -root rootURI option specifies the root resource in the Eyeball configuration. If this option is omitted, eye:eyeball is used by default. rootURI is prefix-expanded using the prefixes in the configuration file.
-root my:root -root my:sparse-config -root urn:x-hp:eyeball-roots:special
The -set option allows command-line tweaks to the configuration,
eg for enabling checking URIs for empty local names.
You will rarely need to use this; it is presented here because of
its association with the -config
and -root
options.
Each Setting has the form S.P=O
and adds the statement
(S' P' O')
to the configuration.
The current Eyeball converts the components of the S.P=O
string
into RDF nodes S'
, P'
, O'
using some special rules:
"
or '
, is
treated as a literal whose lexical form extends to the matching
closing quote. Note: (a)
literals with embedded spaces are not supported; (b) your
command-line interpreter may treat quotes specially, and to allow
the quotes to pass through to Eyeball, you'll have to use another
(different) pair of quotes!_
is treated as a blank node with
that label.rdf:
) that prefix is expanded using
the prefixes of the configuration file. If it has no prefix, it is
as though the empty prefix was specified: in the default
configuration file, that is set to the Eyeball namespace, so it is
as though the prefix eye:
had been used.For example, to enable the URI inspectors non-default reporting of URIs with empty local names, use:
-set URIInspector.reportEmptyLocalNames="'true'"
Note the nested different quotes required to pass 'true' to Eyeball so that it can interpret this as a literal.
The various Eyeball inspectors are given short names in the configuration file. By default, an Eyeball check uses a specific set of inspectors with short name defaultInspectors. Additional inspectors can be enabled using the -include option, and default inspectors can be disabled using the -exclude option. See below for the available inspectors and their short names, and see inspectors configuration for how to configure inspectors.
-include list all-typed -exclude cardinality -include owl -exclude consistent-type
The -assume References identifies any assumed schemas used to specify the predicates and classes of the data model. The reference may be a file name or a URL (and may be mapped by the file manager).
Eyeball automatically assumes the RDF and RDFS schemas, and the built-in XSD datatype classes. The short name owl can be used to refer to the OWL schema, dc to the Dublin Core schema, dcterms to the Dublin Core terms schema, and dc-all to both.
-assume owl -assume owl dc-all -assume owl my-ontology.owl
If -sign is specified, Eyeball first does a -check. If no problem reports are generated, Eyeball writes a signed version of the current model to the standard output. The signature records the Eyeball configuration used and a weak hash of the model. If the input model is already signed, that signature is discarded before computing the new signature and writing the output.
If -accept is specified, the model is checked for its signature. If it is not signed, or if the signature does not match the content of the model -- either the hash fails, or the recorded configuration is not sufficient -- a problem is reported; otherwise not.
The intended use of -sign and -accept is that an application can require signed models which have passed some minimum set of inspections. The application code can then rely on the model having the desired properties, without having to run potentially expensive validation checks every time a model is loaded.
Important. Model signing is intended to catch careless mistakes, not for security against malicious users.
Eyeball will print its version on the standard error stream (currently "Eyeball 2.1 (Nova Embers)").
Normally Eyeball issues its report or signed model to the standard output and exits with code 0 (success) or 1 (failure) with no additional output. Specifying -remark causes it to report success or some problems reported to standard error.
These operations are not currently documented. Try them at your peril: -repair may attempt to update your models.
The eyeball reports are written to the standard output; by default, the reports appear as text (RDF rendered by omitting the subjects - which are all blank nodes - and lightly prettifying the predicate and object). To change the rendering style, supply the -render option with the name of the renderer as its value. Eyeball comes with N3, XML, and text renderers; the Eyeball config file associates renderer names with their classes.
-render n3 -render rdf
If any of the data or schema are identified by an http: URL, and you are behind a firewall, you will need specify the proxy to Java using system properties; one way to do this is by using the Java command line options:
-DproxySet=true -DproxyHost=theProxyHostName -DproxyPort=theProxyPortNumber
Eyeball comes with a collection of inspectors that do relatively simple checks.
Checks that every predicate that appears in the model is declared
in some -assumed schema or owl:import
ed model -- that is, is
given rdf:type
rdf:Property
or some subclass of it.
Checks that every resource in the model that is used as a class,
ie that appears as the object of an rdf:type
, rdfs:domain
, or
rdfs:range
statement, or as the subject or object of an
rdfs:subClassOf
statement, has been declared as a Class
in the
-assumed schemas or in the model under test.
Checks that every URI in the model is well-formed according to the rules of the Jena IRI library. May apply additional rules specified in the configuration file: see uri configuration later for details.
Checks literals for syntactically correct language codes, syntactically correct datatype URIs (using the same rules as the URIInspector), and conformance of the lexical form of typed literals to their datatype.
The PrefixInspector checks that the prefix declarations of the
model have namespaces that are valid URIs and that if the prefix
name is "well-known" (rdf
, rdfs
, owl
, xsd
, and dc
) then
the associated URI is the one usually associated with the prefix.
The PrefixInspector also reports a problem if any prefix looks like
an Jena automatically-generated prefix, j.<i>Number</i>
. (Jena
generates these prefixes when writing RDF/XML if the XML
syntactically requires a prefix but the model hasn't defined one.)
Checks that every URI in the model with a namespace which is mentioned in some schema is one of the URIs declared for that namespace -- that is, it assumes that the schemas define a closed set of URIs.
The inspector may be configured to suppress this check for specified namespaces: see vocabulary configuration later.
This inspector looks for "suspicious restrictions" which have some of the OWL restriction properties but not exactly one owl:onProperty and exactly one constraint (owl:allValuesFrom, etc).
The SparqlDrivenInspector is configured according to configuring the SPARQL-driven inspector, and applies arbitrary SPARQL queries to the model. The queries can be required to match or prohibited from matching; a problem is reported if the constraint fails.
Checks that all URI and bnode resources in the model have an
rdf:type property in the model or the schema(s). If there is a
statement in the configuration with property eye:checkLiteralTypes
and value eye:true
, also checks that every literal has a type or
a language. Not in the default set of inspectors.
Checks that every subject in the model can be given a type which is the intersection of the subclasses of all its "attached" types -- a "consistent type".
For example, if the model contains three types Top
, Left
, and
Right
, with Left
and Right
both being subtypes of Top
and
with no other subclass statements, then some S
with rdf:type
s
Left
and Right
would generate this warning.
Looks for classes C that are subclasses of cardinality
restrictions on some property P with cardinality range min to
max. For any X of rdf:type
C, it checks that the number of
values of P is in the range min..max and generates a report if
it isn't.
Literals are counted as distinct if their values (not just their
lexical form) are distinct. Resources are counted as distinct if
they have different case-sensitive URIs: the CardinalityInspector
takes no account of owl:sameAs
statements.
The ListInspector performs two separate checks:
The typed list idiom is boilerplate OWL for defining a type which is List-of-T for some type T. It takes the form:
my:EList a owl:Class ; rdfs:subClassOf rdf:List ; rdfs:subClassOf [owl:onProperty rdf:first; owl:allValuesFrom my:Element] ; rdfs:subClassOf [owl:onProperty rdf:rest; owl:allValuesFrom my:EList] .
The type my:Element
is the element type of the list, and the type
EList
is the resulting typed list. The list inspector checks that
all the subclasses of rdf:List
(such as EList above) that are
also subclasses of any bnode (such as the two other superclasses of
EList)that has any property (eg, owl:onProperty) that has as
an object either rdf:first
or rdf:rest
is a subclass defined by
the full idiom above: if not, it reports it as a
suspectListIdiom
.
Eyeball generates its reports as items in a model. Each item has
rdf:type
eye:Item
, and its other properties determine what
problem report it is. The default text renderer displays a
prettified form of each item; use -render n3 to expose the
complete report structure.
One of the item's properties is its main property, which identifies the problem; the others are qualifications supplying additional detail.
[] eye:unknownPredicate "*URIString*".
The predicate with the given URI is not defined in any of the -assumed schemas.
[] eye:unknownClass "*URIString*".
The resource with the given URI is used as a Class, but not defined in any of the -assumed schemas.
[] eye:badURI "*URIString*"; eye:forReason *Reason*.
The URIString isn't legal as a URI, or is legal but fails a user-specified spelling constraint. Reason is a resource or string identifying the reason.
reason | explanation |
---|---|
eye:uriContainsSpaces | the URI contains unencoded spaces, probably as a result of sloppy use of file: URLs. |
eye:uriFileInappropriate | a URI used as a namespace is a file: URI, which is inappropriate as a global identifier. |
eye:uriHasNoScheme | a URI has no scheme field, probably a misused relative URI. |
eye:schemeShouldBeLowercase | the scheme part of a URI is not lower-case; while technically correct, this is not usual practice. |
eye:uriFailsPattern | a URI fails the pattern appropriate to its schema (as defined in the configuration for this eyeball). |
eye:unrecognisedScheme | the URI scheme is unknown, perhaps a misplaced QName. |
eye:uriNoHttpAuthority | an http: URI has no authority (domain name/port) component. |
eye:uriSyntaxFailure | the URI can't be parsed using the general URI syntax, even with any spaces removed. |
eye:namespaceEndsWithNameCharacter | a namespace URI ends in a character that can appear in a name, leading to possible ambiguities. |
eye:uriHasNoLocalname | a URI has no local name according to the XML name-splitting rules. (For example, the URI http://x.com/foo#12345 has no local name because a local name cannot start with a digit.) |
"did not match required pattern Taili for prefix Head". | This badURI starts with Head, but the remainder doesn't match any of the Tailis associated with that prefix. |
"matched prohibited pattern Tail for prefix Head". | This badURI starts with Head, and the remainder matched a prohibited Tail associated with that prefix. |
[] eye:badLanguage "*badCode*"; eye:onLiteral "*spelling*".
A literal with the lexical form spelling has the illegal language code badCode.
[] eye:badDatatypeURI "*badURI*"; eye:onLiteral "*spelling*".
A literal with the lexical form spelling has the illegal datatype URI badURI.
[] eye:badLexicalForm "*spelling*"; eye:forDatatype "*dtURI*".
A literal with the datatype URI dtURI has the lexical form spelling, which isn't legal for that datatype.
[] eye:badNamespaceURI "*URIString*" ; eye:onPrefix "*prefix*" ; eye:forReason *Reason*.
The namespace URIString for the declaration of prefix is suspicious for the given Reason (see the URIInspector reports for details of the possible reasons).
[] eye:jenaPrefixFound "*j.Digits*"; eye:forNamespace "*URIString*".
The namespace URIString has an automatically-generated Jena prefix.
[] eye:multiplePrefixesForNamespace "*NameSpace*" ; eye:onPrefix "*prefix<sub>1</sub>"* ...
There are multiple prefix declarations for NameSpace, namely, prefix1 etc.
[] eye:notFromSchema "*NameSpace*"; eye:onResource *Resource*.
The Resource has a URI in the NameSpace, but isn't declared in the schema associated with that NameSpace.
[] eye:suspiciousRestriction *R*; eye:forReason *Reason*...
The presumed restriction R is suspicious for the given Reasons:
eye:missingOnProperty
-- there is no owl:onProperty
property in this suspicious restriction.eye:multipleOnProperty
-- there are multiple owl:onProperty
properties in this suspicious restriction.eye:missingConstraint
-- there is no owl:hasValue
,
owl:allValuesFrom
, owl:someValuesFrom
, or
owl:[minC|maxC|c]ardinality
property in this suspicious
restriction.eye:multipleConstraint
-- there are multiple constraints (as
above) in this suspicious restriction.The restriction R is identified by (a) supplying its immediate properties, and (b) identifying its named equivalent classes and subclasses.
[] eye:sparqlRequireFailed "*message*".
A SPARQL query that was required to succeed against the model did not. The message is either the query that failed or a meaningful description, depending on the inspector configuration.
[] eye:sparqlProhibitFailed "*message*".
A SPARQL query that was required to fail against the model did not. The message is either the query that succeeded or a meaningful description, depending on the inspector configuration.
[] eye:shouldHaveType *Resource*.
The Resource has no rdf:type
. Note that when using models with
inference, this report is unlikely, since inference may well give
the resource a type even if it has no explicit type in the original
model.
[] eye:noConsistentTypeFor *URI* ; eye:hasAttachedType *TypeURI<sub>i</sub>* ...
The resource URI has been given the various types TypeURIi, but if we assume that subtypes are disjoint unless otherwise specified, these types have no intersection.
The ConsistentTypeInspector must do at least some type inference.
This release of Eyeball compromises by doing RDFS inference
augmented by (very) limited union and intersection reasoning, as
described in the Jena rules in etc/owl-like.rules
, so its reports
must be treated with caution. Even with these restrictions, doing
type inference over a large model is costly: you may need to
suppress it with -exclude
until any other warnings are dealt
with.
While, technically, a resource with no attached types at all is automatically inconsistent, Eyeball quietly ignores such resources, since they turn up quite often in simple RDF models.
[] eye:cardinalityFailure *Subject*; eye:onType *T*; eye:onProperty *P*
The Subject has a cardinality-constrained rdf:type
T with
owl:onProperty
P, but the number of distinct values in the
model isn't consistent with the cardinality restriction.
Additional properties describe the cardinality restriction and the values found:
eye:numValues
N: the number of distinct values for
(Subject, P) in the model.eye:cardinality
[eye:min
min; eye:max
max]: the
minimum and maximum cardinalities permitted.eye:values
Set: A blank node of type eye:Set
with an
rdfs:member
value for each of the values of P.[] eye:illFormedList *URI* ; eye:because [eye:element *index<sub>i</sub>*; *Problem<sub>i~*]~i</sub> ...
The list starting at URI is ill-formed because the element with index indexi had Problemi. The possible problems are:
eye:hasNoRest
-- the element has no rdf:rest
property.eye:hasMultipleRests
-- the element has more than one
rdf:rest
property.eye:hasNoFirst
-- the element has no rdf:first
property.eye:hasMultipleFirsts
-- the element has more than one
rdf:rest
property.[] eye:suspectListIdiom *Type*.
The resource Type looks like it's supposed to be a use of the "typed list idiom", but it isn't complete/accurate.
The Eyeball command-line utility is configured by files (or URLs) specified on the command line: their RDF contents are unioned together into a single config model. If no config file is specified, then etc/eyeball-config.n3 is loaded. The configuration file is a Jena assembler description (see Assemblers) with added Eyeball vocabulary.
Eyeball is also configured by the location-mapping file etc/location-mapping.n3. The Eyeball jar contains copies of both the default config and the location mapper; these are used by default. You can provide your own etc/eyeball-config.n3 file earlier on your classpath or in your current directory; this config replaces the default. You may provide additional location-mapping files earlier on your classpath or in your current directory.
To avoid having to quote schema names in full on the Eyeball command line, (collections of) schemas can be given short names. [] eye:shortName shortNameLiteral ; eye:schema fullSchemaURL ... .
A shortname can name several schemas. The Eyeball delivery has the short names rdf, rdfs, owl, and dc for the corresponding schemas (and mirror versions of those schemas so that they don't need to be downloaded each time Eyeball is run.)
The inspectors that Eyeball runs over the model are specified by
eye:inspector properties of inspector resources. These resources
are identified by eye:shortName
s (supplied on the command line).
Each such property value must be a plain string literal whose value
is the full name of the Inspector class to load and run; see the
Javadoc of Inspector for details.
An inspector resource may refer to other inspector resources to
include their inspectors, using either of the two properties
eye:include
or eye:includeByName
. The value of an include
property should be another inspector resource; the value of an
includeByName
property should be the shortName
of an inspector
resource.
As well as applying the standard URI rules, Eyeball allows extra
pattern-oriented checks to be applied to URIs. These are specified
by eye:check
properties of the URIInspector
object in the
configuration.
The object of an eye:check
property is a bnode with eye:prefix
,
eye:prohibit
, and eye:require
properties. The objects of these
properties must be string literals.
If a URI U can be split into a prefix P and suffix S, and there is a check property with that prefix, and either:
then a problem is reported. If there are multiple prohibit
s, then
a problem is reported if any prohibition is violated; if there
are multiple require
s, a problem is reported if none of them
succeed.
eye:URIInspector eye:check [eye:prefix "urn:x-hp:"; eye:prohibit ".*:.*"] ; [eye:prefix "http://example.com/"; eye:require ".*eyeball.*"]
The prefixes, requires, and prohibits are treated as Java patterns.
The URI inspector can be configured to report URIs with an empty
local name. These arise because the meaning of "local name" comes
from XML, and in XML a local name must start with an NCName
character, typically a letter but not a digit. Hence URIs like
http://example.com/productCode#1829
have an empty local name.
This is sometimes confusing.
To report empty local names, add the property
eye:reportEmptyLocalNames
to the inspector eye:URIInspector
with the property value true
. You may edit the configuration file
or use the -set
command-line option.
The vocabulary inspector defaults to assuming that schema
namespaces are closed. To disable this for specified namespaces,
the inspector object in the configuration can be given
eye:openNamespace
properties.
The object of each of these properties must be a resource; the URI of this resource is an open namespace for which the inspector will not report problems.
eye:VocabularyInspector eye:openNamespace <http://example.com/examples#>
The SPARQL inspector object in the configuration may be given
eye:sparql
properties whose objects are resources specifying
SPARQL queries and problem messages.
eye:SparqlDrivenInspector eye:sparql [...]
The resource may specify a SPARQL query which must succeed in the model, and a message to produce if it does not.
eye:SparqlDrivenInspector eye:sparql [eye:require "select * where {?s ?p ?o}"; eye:message "must be non-empty"]
If the query is non-trivial, the string may contain a reference to a file containing the query, rather than the entire query.
eye:require "@'/home/kers/example/query-one.sparql'"
The quoted filename is read using the Jena file manager and so respects any filename mappings. "@" characters not followed by "'" are not subject to substitution, except that the sequence "@@" is replaced by "@".
Using eye:prohibit
rather than eye:require
means that the
problem is reported if the query succeeds, rather than if it
fails.
The renderer class that Eyeball uses to render the report into text is giving in the config file by triples of the form:
[] eye:renderer FullClassName ; eye:shortName ShortClassHandler
The FullClassName
is a string literal giving the full class name
of the rendering class. That class must implement the Renderer
interface and have a constructor that takes a Resource
, its
configuration root, as its argument.
The ShortClassHandle
is a string literal giving the short name
used to refer to the class. The default short name used is
default. There should be no more than one eye:shortName
statement with the same ShortClassHandle in the configuration file,
but the same class can have many different short names.
The TextRenderer
supports an additional property eye:labels
to
allow the appropriate labels for an ontology to be supplied to the
renderer. Each object of a eye:labels
statement names a model;
all the rdfs:label
statements in that model are used to supply
strings which are used to render resources.
The model names are strings which are interpreted by Jena's
FileManager
, so they may be redirected using Jena's file
mappings.
Eyeball can be used from within Java code; the command line merely provides a convenient external interface.
An Eyeball object has three subcomponents: the assumptions against which the model is to be checked, the inspectors which do the checking, and the renderer used to display the reports.
The assumptions are bundled into a single OntModel. Multiple assumptions can be supplied either by adding them as sub-models or by loading their content directly into the OntModel.
The inspectors are supplied as a single Inspector object. The
method Inspector.Operations.create(List)
creates a single
Inspector from a list of Inspectors; this inspector delegates all
its inspection methods to all of its sub-inspectors.
The renderer can be anything that implements the (simple) renderer interface.
To create an Eyeball:
Eyeball eyeball = new Eyeball( inspector, assumptions, renderer );
Models to be inspected are provided as OntModels. The problems are delivered to a Report object, where they are represented as an RDF model.
eyeball.inspect( report, ontModelToBeInspected )
The result is that same report object. The Report::model() method delivers an RDF model which describes the problems found by the inspection. The inspections supplied in the distribution use the EYE vocabulary, and are used in the standard reports:
Every report item in the model is a blank node with
rdf:type eye:Item
. See earlier sections for the descriptions of
the properties attached to an Item.
The provided ant script can be used to rebuild Eyeball from source:
ant clean build jar
(Omitting clean
will do an incremental build, useful for small
changes.)
The libraries required by Eyeball are all in the lib
directory,
including the necessary Jena jars.
To make a new inspector available to Eyeball, a new Inspector class must be created and that class has to be described in the Eyeball configuration.
Any inspector must implement the Inspector interface, which has four operations:
r
is the Report
object which will accept the reports in this
inspection; assume
is the model containing the assumed
ontologies. begin
is responsible for declaring this inspectors
report properties.m
, issuing reports to r
.s
, issuing reports to r
.Typically end
and one of inspectModel
or inspectStatement
do
nothing.
An inspector must also have a constructor that takes a Resource
argument. When Eyeball creates the Inspector object, it passes the
Resource
which is the root of this inspector's configuration.
(This is, for example, how the SPARQL-driven inspector receives the
query strings to use.)
Developers may find the class InpsectorBase
useful; it has empty
implementations for all the Inspector
methods. They may also find
InspectorTestBase
useful when writing their inspector's tests,
both for its convenience methods and because it requires that their
class has the appropriate constructors.
Eyeball reports are statements in a report model. To let the
renderer know which property of a report is the "main" one, and
which order the other properties should appear in, the inspector's
begin
method should declare the properties:
r.declareProperty( EYE.badDatatypeURI ); r.declareOrder( EYE.badLanguage, EYE.onLiteral );
declareProperty(P)
announces that P
is a report property of
this inspector. declareOrder(F,S)
says that both F
and S
are
report properties, and that F
should appear before S
in the
rendered report.
Reports are made up of report items, which are the subjects of
the report properties. To create a report item, use one of
reportItem()
or reportItem(S)
. The second form is appropriate
when the report is attached to some statement S
of the model
being inspected; a report renderer will attempt to display S
.
To add the main property to a report item R
, use
R.addMainProperty(P,O)
; to add non-main properties, use
R.addProperty(P,O)
.
To add an inspector to a configuration file, choose a URI for it
(here we're using my:Fresh
and assuming a prefix declaration for
my:
) and a short name (here, "fresh") and add a description to
the configuration file:
my:Fresh a eye:Inspector ; eye:shortName "fresh" ; rdfs:label "fresh checks for my application" ; eye:className "full.path.to.Fresh" .
Replace full.path.to.Fresh
with the full classname of your
inspector. Now you can use Fresh
by adding -include fresh to
the Eyeball command line (and ensuring that the class is on your
classpath).
If you want Fresh
to be included by default, then you must add it
as an eye:inspector
property of the configuration root, eg:
eye:eyeball a eye:Eyeball ; eye:inspector eye:PrefixInspector, # as delivered my:FreshInspector, # new inspector eye:URIInspector, # as delivered ...