Class DocumentBuilderFactory
- java.lang.Object
-
- javax.xml.parsers.DocumentBuilderFactory
public abstract class DocumentBuilderFactory extends Object
Defines a factory API that enables applications to obtain a parser that produces DOM object trees from XML documents.
- Since:
- 1.4
Constructor Summary
Modifier | Constructor | Description |
---|---|---|
protected | DocumentBuilderFactory() | Protected constructor to prevent instantiation. |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
abstract Object | getAttribute(String name) | Allows the user to retrieve specific attributes on the underlying implementation. |
abstract boolean | getFeature(String name) | Get the state of the named feature. |
Schema | getSchema() | Gets the |
boolean | isCoalescing() | Indicates whether or not the factory is configured to produce parsers which converts CDATA nodes to Text nodes and appends it to the adjacent (if any) Text node. |
boolean | isExpandEntityReferences() | Indicates whether or not the factory is configured to produce parsers which expand entity reference nodes. |
boolean | isIgnoringComments() | Indicates whether or not the factory is configured to produce parsers which ignores comments. |
boolean | isIgnoringElementContentWhitespace() | Indicates whether or not the factory is configured to produce parsers which ignore ignorable whitespace in element content. |
boolean | isNamespaceAware() | Indicates whether or not the factory is configured to produce parsers which are namespace aware. |
boolean | isValidating() | Indicates whether or not the factory is configured to produce parsers which validate the XML content during parse. |
boolean | isXIncludeAware() | Get state of XInclude processing. |
static DocumentBuilderFactory | newDefaultInstance() | Creates a new instance of the |
abstract DocumentBuilder | newDocumentBuilder() | Creates a new instance of a |
static DocumentBuilderFactory | newInstance() | Obtain a new instance of a |
static DocumentBuilderFactory | newInstance(String factoryClassName,
ClassLoader classLoader) | Obtain a new instance of a |
abstract void | setAttribute(String name,
Object value) | Allows the user to set specific attributes on the underlying implementation. |
void | setCoalescing(boolean coalescing) | Specifies that the parser produced by this code will convert CDATA nodes to Text nodes and append it to the adjacent (if any) text node. |
void | setExpandEntityReferences(boolean expandEntityRef) | Specifies that the parser produced by this code will expand entity reference nodes. |
abstract void | setFeature(String name,
boolean value) | Set a feature for this |
void | setIgnoringComments(boolean ignoreComments) | Specifies that the parser produced by this code will ignore comments. |
void | setIgnoringElementContentWhitespace(boolean whitespace) | Specifies that the parsers created by this factory must eliminate whitespace in element content (sometimes known loosely as 'ignorable whitespace') when parsing XML documents (see XML Rec 2.10). |
void | setNamespaceAware(boolean awareness) | Specifies that the parser produced by this code will provide support for XML namespaces. |
void | setSchema(Schema schema) | Set the |
void | setValidating(boolean validating) | Specifies that the parser produced by this code will validate documents as they are parsed. |
void | setXIncludeAware(boolean state) | Set state of XInclude processing. |
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Constructor Detail
DocumentBuilderFactory
protected DocumentBuilderFactory()
Protected constructor to prevent instantiation. Use newInstance()
.
Method Detail
newDefaultInstance
public static DocumentBuilderFactory newDefaultInstance()
Creates a new instance of the DocumentBuilderFactory
builtin system-default implementation.
- Returns:
- A new instance of the
DocumentBuilderFactory
builtin system-default implementation. - Since:
- 9
newInstance
public static DocumentBuilderFactory newInstance()
Obtain a new instance of a DocumentBuilderFactory
. This static method creates a new factory instance. This method uses the following ordered lookup procedure to determine the DocumentBuilderFactory
implementation class to load:
- Use the
javax.xml.parsers.DocumentBuilderFactory
system property. -
Use the configuration file "jaxp.properties". The file is in standard
Properties
format and typically located in theconf
directory of the Java installation. It contains the fully qualified name of the implementation class with the key being the system property defined above.The jaxp.properties file is read only once by the JAXP implementation and its values are then cached for future use. If the file does not exist when the first attempt is made to read from it, no further attempts are made to check for its existence. It is not possible to change the value of any property in jaxp.properties after it has been read for the first time.
-
Use the service-provider loading facility, defined by the
ServiceLoader
class, to attempt to locate and load an implementation of the service using the default loading mechanism: the service-provider loading facility will use the current thread's context class loader to attempt to load the service. If the context class loader is null, the system class loader will be used. -
Otherwise, the system-default implementation is returned.
Once an application has obtained a reference to a DocumentBuilderFactory
it can use the factory to configure and obtain parser instances.
Tip for Trouble-shooting
Setting the jaxp.debug
system property will cause this method to print a lot of debug messages to System.err
about what it is doing and where it is looking at.
If you have problems loading DocumentBuilder
s, try:
java -Djaxp.debug=1 YourProgram ....
- Returns:
- New instance of a
DocumentBuilderFactory
- Throws:
-
FactoryConfigurationError
- in case of service configuration error or if the implementation is not available or cannot be instantiated.
newInstance
public static DocumentBuilderFactory newInstance(String factoryClassName, ClassLoader classLoader)
Obtain a new instance of a DocumentBuilderFactory
from class name. This function is useful when there are multiple providers in the classpath. It gives more control to the application as it can specify which provider should be loaded.
Once an application has obtained a reference to a DocumentBuilderFactory
it can use the factory to configure and obtain parser instances.
Tip for Trouble-shooting
Setting the jaxp.debug
system property will cause this method to print a lot of debug messages to System.err
about what it is doing and where it is looking at.
If you have problems try:
java -Djaxp.debug=1 YourProgram ....
- Parameters:
-
factoryClassName
- fully qualified factory class name that provides implementation ofjavax.xml.parsers.DocumentBuilderFactory
. -
classLoader
-ClassLoader
used to load the factory class. Ifnull
currentThread
's context classLoader is used to load the factory class. - Returns:
- New instance of a
DocumentBuilderFactory
- Throws:
-
FactoryConfigurationError
- iffactoryClassName
isnull
, or the factory class cannot be loaded, instantiated. - Since:
- 1.6
- See Also:
newInstance()
newDocumentBuilder
public abstract DocumentBuilder newDocumentBuilder() throws ParserConfigurationException
Creates a new instance of a DocumentBuilder
using the currently configured parameters.
- Returns:
- A new instance of a DocumentBuilder.
- Throws:
-
ParserConfigurationException
- if a DocumentBuilder cannot be created which satisfies the configuration requested.
setNamespaceAware
public void setNamespaceAware(boolean awareness)
Specifies that the parser produced by this code will provide support for XML namespaces. By default the value of this is set to false
- Parameters:
-
awareness
- true if the parser produced will provide support for XML namespaces; false otherwise.
setValidating
public void setValidating(boolean validating)
Specifies that the parser produced by this code will validate documents as they are parsed. By default the value of this is set to false
.
Note that "the validation" here means a validating parser as defined in the XML recommendation. In other words, it essentially just controls the DTD validation. (except the legacy two properties defined in JAXP 1.2.)
To use modern schema languages such as W3C XML Schema or RELAX NG instead of DTD, you can configure your parser to be a non-validating parser by leaving the setValidating(boolean)
method false
, then use the setSchema(Schema)
method to associate a schema to a parser.
- Parameters:
-
validating
- true if the parser produced will validate documents as they are parsed; false otherwise.
setIgnoringElementContentWhitespace
public void setIgnoringElementContentWhitespace(boolean whitespace)
Specifies that the parsers created by this factory must eliminate whitespace in element content (sometimes known loosely as 'ignorable whitespace') when parsing XML documents (see XML Rec 2.10). Note that only whitespace which is directly contained within element content that has an element only content model (see XML Rec 3.2.1) will be eliminated. Due to reliance on the content model this setting requires the parser to be in validating mode. By default the value of this is set to false
.
- Parameters:
-
whitespace
- true if the parser created must eliminate whitespace in the element content when parsing XML documents; false otherwise.
setExpandEntityReferences
public void setExpandEntityReferences(boolean expandEntityRef)
Specifies that the parser produced by this code will expand entity reference nodes. By default the value of this is set to true
- Parameters:
-
expandEntityRef
- true if the parser produced will expand entity reference nodes; false otherwise.
setIgnoringComments
public void setIgnoringComments(boolean ignoreComments)
Specifies that the parser produced by this code will ignore comments. By default the value of this is set to false
.
- Parameters:
-
ignoreComments
-boolean
value to ignore comments during processing
setCoalescing
public void setCoalescing(boolean coalescing)
Specifies that the parser produced by this code will convert CDATA nodes to Text nodes and append it to the adjacent (if any) text node. By default the value of this is set to false
- Parameters:
-
coalescing
- true if the parser produced will convert CDATA nodes to Text nodes and append it to the adjacent (if any) text node; false otherwise.
isNamespaceAware
public boolean isNamespaceAware()
Indicates whether or not the factory is configured to produce parsers which are namespace aware.
- Returns:
- true if the factory is configured to produce parsers which are namespace aware; false otherwise.
isValidating
public boolean isValidating()
Indicates whether or not the factory is configured to produce parsers which validate the XML content during parse.
- Returns:
- true if the factory is configured to produce parsers which validate the XML content during parse; false otherwise.
isIgnoringElementContentWhitespace
public boolean isIgnoringElementContentWhitespace()
Indicates whether or not the factory is configured to produce parsers which ignore ignorable whitespace in element content.
- Returns:
- true if the factory is configured to produce parsers which ignore ignorable whitespace in element content; false otherwise.
isExpandEntityReferences
public boolean isExpandEntityReferences()
Indicates whether or not the factory is configured to produce parsers which expand entity reference nodes.
- Returns:
- true if the factory is configured to produce parsers which expand entity reference nodes; false otherwise.
isIgnoringComments
public boolean isIgnoringComments()
Indicates whether or not the factory is configured to produce parsers which ignores comments.
- Returns:
- true if the factory is configured to produce parsers which ignores comments; false otherwise.
isCoalescing
public boolean isCoalescing()
Indicates whether or not the factory is configured to produce parsers which converts CDATA nodes to Text nodes and appends it to the adjacent (if any) Text node.
- Returns:
- true if the factory is configured to produce parsers which converts CDATA nodes to Text nodes and appends it to the adjacent (if any) Text node; false otherwise.
setAttribute
public abstract void setAttribute(String name, Object value) throws IllegalArgumentException
Allows the user to set specific attributes on the underlying implementation.
All implementations that implement JAXP 1.5 or newer are required to support the XMLConstants.ACCESS_EXTERNAL_DTD
and XMLConstants.ACCESS_EXTERNAL_SCHEMA
properties.
- Setting the
XMLConstants.ACCESS_EXTERNAL_DTD
property restricts the access to external DTDs, external Entity References to the protocols specified by the property. If access is denied during parsing due to the restriction of this property,SAXException
will be thrown by the parse methods defined byDocumentBuilder
. - Setting the
XMLConstants.ACCESS_EXTERNAL_SCHEMA
property restricts the access to external Schema set by the schemaLocation attribute to the protocols specified by the property. If access is denied during parsing due to the restriction of this property,SAXException
will be thrown by the parse methods defined byDocumentBuilder
.
- Parameters:
-
name
- The name of the attribute. -
value
- The value of the attribute. - Throws:
-
IllegalArgumentException
- thrown if the underlying implementation doesn't recognize the attribute.
getAttribute
public abstract Object getAttribute(String name) throws IllegalArgumentException
Allows the user to retrieve specific attributes on the underlying implementation.
- Parameters:
-
name
- The name of the attribute. - Returns:
- value The value of the attribute.
- Throws:
-
IllegalArgumentException
- thrown if the underlying implementation doesn't recognize the attribute.
setFeature
public abstract void setFeature(String name, boolean value) throws ParserConfigurationException
Set a feature for this DocumentBuilderFactory
and DocumentBuilder
s created by this factory.
Feature names are fully qualified URI
s. Implementations may define their own features. A ParserConfigurationException
is thrown if this DocumentBuilderFactory
or the DocumentBuilder
s it creates cannot support the feature. It is possible for a DocumentBuilderFactory
to expose a feature value but be unable to change its state.
All implementations are required to support the XMLConstants.FEATURE_SECURE_PROCESSING
feature. When the feature is:
-
true
: the implementation will limit XML processing to conform to implementation limits. Examples include entity expansion limits and XML Schema constructs that would consume large amounts of resources. If XML processing is limited for security reasons, it will be reported via a call to the registeredErrorHandler.fatalError(SAXParseException exception)
. SeeDocumentBuilder.setErrorHandler(org.xml.sax.ErrorHandler errorHandler)
. -
false
: the implementation will processing XML according to the XML specifications without regard to possible implementation limits.
- Parameters:
-
name
- Feature name. -
value
- Is feature statetrue
orfalse
. - Throws:
-
ParserConfigurationException
- if thisDocumentBuilderFactory
or theDocumentBuilder
s it creates cannot support this feature. -
NullPointerException
- If thename
parameter is null. - Since:
- 1.5
getFeature
public abstract boolean getFeature(String name) throws ParserConfigurationException
Get the state of the named feature.
Feature names are fully qualified URI
s. Implementations may define their own features. An ParserConfigurationException
is thrown if this DocumentBuilderFactory
or the DocumentBuilder
s it creates cannot support the feature. It is possible for an DocumentBuilderFactory
to expose a feature value but be unable to change its state.
- Parameters:
-
name
- Feature name. - Returns:
- State of the named feature.
- Throws:
-
ParserConfigurationException
- if thisDocumentBuilderFactory
or theDocumentBuilder
s it creates cannot support this feature. - Since:
- 1.5
getSchema
public Schema getSchema()
Gets the Schema
object specified through the setSchema(Schema schema)
method.
- Returns:
- the
Schema
object that was last set through thesetSchema(Schema)
method, or null if the method was not invoked since aDocumentBuilderFactory
is created. - Throws:
-
UnsupportedOperationException
- When implementation does not override this method. - Since:
- 1.5
setSchema
public void setSchema(Schema schema)
Set the Schema
to be used by parsers created from this factory.
When a Schema
is non-null, a parser will use a validator created from it to validate documents before it passes information down to the application.
When errors are found by the validator, the parser is responsible to report them to the user-specified ErrorHandler
(or if the error handler is not set, ignore them or throw them), just like any other errors found by the parser itself. In other words, if the user-specified ErrorHandler
is set, it must receive those errors, and if not, they must be treated according to the implementation specific default error handling rules.
A validator may modify the outcome of a parse (for example by adding default values that were missing in documents), and a parser is responsible to make sure that the application will receive modified DOM trees.
Initially, null is set as the Schema
.
This processing will take effect even if the isValidating()
method returns false
.
It is an error to use the http://java.sun.com/xml/jaxp/properties/schemaSource
property and/or the http://java.sun.com/xml/jaxp/properties/schemaLanguage
property in conjunction with a Schema
object. Such configuration will cause a ParserConfigurationException
exception when the newDocumentBuilder()
is invoked.
Note for implementors
A parser must be able to work with any Schema
implementation. However, parsers and schemas are allowed to use implementation-specific custom mechanisms as long as they yield the result described in the specification.
- Parameters:
-
schema
-Schema
to use ornull
to remove a schema. - Throws:
-
UnsupportedOperationException
- When implementation does not override this method. - Since:
- 1.5
setXIncludeAware
public void setXIncludeAware(boolean state)
Set state of XInclude processing.
If XInclude markup is found in the document instance, should it be processed as specified in XML Inclusions (XInclude) Version 1.0.
XInclude processing defaults to false
.
- Parameters:
-
state
- Set XInclude processing totrue
orfalse
- Throws:
-
UnsupportedOperationException
- When implementation does not override this method. - Since:
- 1.5
isXIncludeAware
public boolean isXIncludeAware()
Get state of XInclude processing.
- Returns:
- current state of XInclude processing
- Throws:
-
UnsupportedOperationException
- When implementation does not override this method. - Since:
- 1.5