Java™ Platform
Standard Ed. 8
compact2, compact3
javax.xml.parsers

Class 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.
    Version:
    $Revision: 1.9 $, $Date: 2010/05/25 16:19:44 $
    • Constructor Detail

      • DocumentBuilderFactory

        protected DocumentBuilderFactory()

        Protected constructor to prevent instantiation. Use newInstance().

    • Method Detail

      • 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 properties file "lib/jaxp.properties" in the JRE directory. This configuration file is in standard java.util.Properties format and 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 it's 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.
        • Uses the service-provider loading facilities, 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 DocumentBuilders, 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 of javax.xml.parsers.DocumentBuilderFactory.
        classLoader - ClassLoader used to load the factory class. If null current Thread's context classLoader is used to load the factory class.
        Returns:
        New instance of a DocumentBuilderFactory
        Throws:
        FactoryConfigurationError - if factoryClassName is null, or the factory class cannot be loaded, instantiated.
        Since:
        1.6
        See Also:
        newInstance()
      • 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.
      • 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 DocumentBuilders created by this factory.

        Feature names are fully qualified URIs. Implementations may define their own features. A ParserConfigurationException is thrown if this DocumentBuilderFactory or the DocumentBuilders 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:

        Parameters:
        name - Feature name.
        value - Is feature state true or false.
        Throws:
        ParserConfigurationException - if this DocumentBuilderFactory or the DocumentBuilders it creates cannot support this feature.
        NullPointerException - If the name parameter is null.
      • getFeature

        public abstract boolean getFeature(String name)
                                    throws ParserConfigurationException

        Get the state of the named feature.

        Feature names are fully qualified URIs. Implementations may define their own features. An ParserConfigurationException is thrown if this DocumentBuilderFactory or the DocumentBuilders 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 this DocumentBuilderFactory or the DocumentBuilders it creates cannot support this feature.
      • 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.

        Initialy, 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 implmentors

        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 or null 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 to true or false
        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
Java™ Platform
Standard Ed. 8

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For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2022, Oracle and/or its affiliates. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.

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