Feature | Description | Property Name | System Property [1] | Value [2] | Action | |
---|---|---|---|---|---|---|
Type | Value | |||||
FILES | A semicolon-delimited list of URIs to locate the catalog files. The URIs must be absolute and have a URL protocol handler for the URI scheme. | javax.xml.catalog.files | javax.xml.catalog.files | String | URIs | Reads the first catalog as the current catalog; Loads others if no match is found in the current catalog including delegate catalogs if any. |
PREFER | Indicates the preference between the public and system identifiers. The default value is public [3]. | javax.xml.catalog.prefer | N/A | String | system |
Searches system entries for a match; Searches public entries when external identifier specifies only a public identifier |
public |
Searches system entries for a match; Searches public entries when there is no matching system entry. | |||||
DEFER | Indicates that the alternative catalogs including those specified in delegate entries or nextCatalog are not read until they are needed. The default value is true. | javax.xml.catalog.defer [4] | javax.xml.catalog.defer | String | true |
Loads alternative catalogs as needed. |
false |
Loads all catalogs[5]. | |||||
RESOLVE | Determines the action if there is no matching entry found after all of the specified catalogs are exhausted. The default is strict. | javax.xml.catalog.resolve [4] | javax.xml.catalog.resolve | String | strict |
Throws CatalogException if there is no match. |
continue |
Allows the XML parser to continue as if there is no match. | |||||
ignore |
Tells the XML parser to skip the external references if there no match. |
[1] There is no System property for the features that marked as "N/A".
[2] The value shall be exactly as listed in this table, case-sensitive.
Any unspecified value will result in IllegalArgumentException
.
[3] The Catalog specification defined complex rules on the prefer attribute. Although the prefer can be public or system, the specification actually made system the preferred option, that is, no matter the option, a system entry is always used if found. Public entries are only considered if the prefer is public and system entries are not found. It is therefore recommended that the prefer attribute be set as public (which is the default).
[4] Although non-standard attributes in the OASIS Catalog specification,
defer
and resolve
are recognized by the Java Catalog API the
same as the prefer
as being an attribute in the catalog entry of the
main catalog. Note that only the attributes specified for the catalog entry
of the main Catalog file will be used.
[5] If the intention is to share an entire catalog store, it may be desirable to
set the property javax.xml.catalog.defer
to false to allow the entire
catalog to be pre-loaded.
Property Precedence
The Catalog Features follow the Property Precedence as described in the module summary with regards to the priority with which their values are retrieved from the various configuration sources such as the JAXP configuration file, system and API properties. In addition to the general configuration sources, the Catalog Features are further supported in the catalog file itself where they can be specified as attributes of the catalog and group entries. When the attributes are specified, they shall take preference over any of the other configuration sources. For example, if aprefer
attribute is set in the catalog file as in
<catalog prefer="public">
, any other input for the "prefer" property
is not necessary or will be ignored.
A CatalogFeatures instance can be created through its builder as illustrated in the following sample code:
CatalogFeatures f = CatalogFeatures.builder()
.with(Feature.FILES, "file:///etc/xml/catalog")
.with(Feature.PREFER, "public")
.with(Feature.DEFER, "true")
.with(Feature.RESOLVE, "ignore")
.build();
JAXP XML Processor Support
The Catalog Features are supported throughout the JAXP processors, including SAX and DOM (javax.xml.parsers
), and StAX parsers (javax.xml.stream
),
Schema Validation (javax.xml.validation
), and XML Transformation
(javax.xml.transform
). The features described above can be set through JAXP
factories or processors that define a setProperty or setAttribute interface.
For example, the following code snippet sets a URI to a catalog file on a SAX
parser through the javax.xml.catalog.files
property:
SAXParserFactory spf = SAXParserFactory.newInstance();
spf.setFeature(XMLConstants.USE_CATALOG, true); [1]
SAXParser parser = spf.newSAXParser();
parser.setProperty(CatalogFeatures.Feature.FILES.getPropertyName(), "file:///etc/xml/catalog");
[1] Note that this statement is not required since the default value of
USE_CATALOG
is true.
The JAXP Processors' support for Catalog depends on both the
USE_CATALOG
feature and the
existence of valid Catalog file(s). A JAXP processor will use the Catalog
only when the feature is true and valid Catalog file(s) are specified through
the javax.xml.catalog.files
property. It will make no attempt to use
the Catalog if either USE_CATALOG
is set to false, or there is no Catalog file specified.
The JAXP processors will observe the default settings of the
CatalogFeatures
. The processors, for example, will
report an Exception by default when no matching entry is found since the
default value of the javax.xml.catalog.resolve
property is strict.
The JAXP processors give preference to user-specified custom resolvers. If such a resolver is registered, it will be used over the CatalogResolver. If it returns null however, the processors will continue resolving with the CatalogResolver. If it returns an empty source, no attempt will be made by the CatalogResolver.
The Catalog support is available for any process in the JAXP library that supports a resolver. The following table lists all such processes.
Processes with Catalog Support
Process | Catalog Entry Type | Example |
---|---|---|
DTDs and external entities | public, system |
The following DTD reference: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> Can be resolved using the following Catalog entry: <public publicId="-//W3C//DTD XHTML 1.0 Strict//EN" uri="catalog/xhtml1-strict.dtd"/> or <systemSuffix systemIdSuffix="html1-strict.dtd" uri="catalog/xhtml1-strict.dtd"/> |
XInclude | uri |
The following XInclude element: <xi:include href="https://openjdk.org/xml/disclaimer.xml"/> can be resolved using a URI entry: <uri name="https://openjdk.org/xml/disclaimer.xml" uri="file:///pathto/local/disclaimer.xml"/> or <uriSuffix uriSuffix="disclaimer.xml" uri="file:///pathto/local/disclaimer.xml"/> |
XSD import | uri |
The following import element: <xsd:import namespace="https://openjdk.org/xsd/XSDImport_person" schemaLocation="https://openjdk.org/xsd/XSDImport_person.xsd"/> can be resolved using a URI entry: <uri name="https://openjdk.org/xsd/XSDImport_person.xsd" uri="file:///pathto/local/XSDImport_person.xsd"/> or <uriSuffix uriSuffix="XSDImport_person.xsd" uri="file:///pathto/local/XSDImport_person.xsd"/> or <uriSuffix uriSuffix="https://openjdk.org/xsd/XSDImport_person" uri="file:///pathto/local/XSDImport_person.xsd"/> |
XSD include | uri |
The following include element: <xsd:include schemaLocation="https://openjdk.org/xsd/XSDInclude_person.xsd"/> can be resolved using a URI entry: <uri name="https://openjdk.org/xsd/XSDInclude_person.xsd" uri="file:///pathto/local/XSDInclude_person.xsd"/> or <uriSuffix uriSuffix="XSDInclude_person.xsd" uri="file:///pathto/local/XSDInclude_person.xsd"/> |
XSL import and include | uri |
The following include element: <xsl:include href="https://openjdk.org/xsl/include.xsl"/> can be resolved using a URI entry: <uri name="https://openjdk.org/xsl/include.xsl" uri="file:///pathto/local/include.xsl"/> or <uriSuffix uriSuffix="include.xsl" uri="file:///pathto/local/include.xsl"/> |
XSL document function | uri |
The document in the following element: <xsl:variable name="dummy" select="document('https://openjdk.org/xsl/list.xml')"/> can be resolved using a URI entry: <uri name="https://openjdk.org/xsl/list.xml" uri="file:///pathto/local/list.xml"/> or <uriSuffix uriSuffix="list.xml" uri="file:///pathto/local/list.xml"/> |
- Since:
- 9
-
Nested Class Summary
Modifier and TypeClassDescriptionstatic class
The Builder class for building the CatalogFeatures object.static enum
A Feature type as defined in the Catalog Features table. -
Method Summary
Modifier and TypeMethodDescriptionstatic CatalogFeatures.Builder
builder()
Returns an instance of the builder for creating the CatalogFeatures object.static CatalogFeatures
defaults()
Returns a CatalogFeatures instance with default settings.Returns the value of the specified feature.
-
Method Details
-
defaults
Returns a CatalogFeatures instance with default settings.- Returns:
- a default CatalogFeatures instance
-
get
Returns the value of the specified feature.- Parameters:
cf
- the type of the Catalog feature- Returns:
- the value of the feature
-
builder
Returns an instance of the builder for creating the CatalogFeatures object.- Returns:
- an instance of the builder
-