Package org.openjdk.jmc.common.util

Class XmlToolkit

java.lang.Object

org.openjdk.jmc.common.util.XmlToolkit

public final class XmlToolkit
extends Object

Class containing helper methods for XML processing.

Method Summary

Modifier and Type	Method	Description
static DocumentBuilderFactory	createDocumentBuildFactoryInstance()	Create a document builder factory with safe settings.
static Element	createElement(Element parentNode, String tagName)	Adds a child element with the name tagName to the parent and returns the new child element.
static Document	createNewDocument(String rootElementName)	Creates a new empty XML document.
static SAXParserFactory	createSAXParserFactory()	Create a SAX parser factory with safe settings.
static TransformerFactory	createTransformerFactory()	Create a transformer factory with safe settings.
static String	escapeAll(String s)
static String	escapeTagContent(String s)
static Element	getChildElementOrNull(Element parent, String name)	Returns the child element with the specified tag name of the specified parent node.
static List<Element>	getChildElementsByTag(Node contextNode, String tag)	Returns all the children from a node with a tag matching the tag argument.
static Element	getOrCreateElement(Element parentNode, String tagName)	Returns the child element with the specified tag name of the specified parent node.
static String	getSetting(Element parent, String settingName, String defaultValue)	Returns the value of the setting with the specified name or a default value if the setting had no value.
static String	getStringValue(Element element)	Returns the content between the tags of the element, for example <tag>hello </tag> where the value is "hello".
static Document	loadDocumentFromFile(File file)	Loads an XML document from the specified file.
static Document	loadDocumentFromStream(InputStream stream)	Loads an XML document from the specified stream.
static Document	loadDocumentFromString(String doc)	Loads an XML document from its string representation.
static String	prettyPrint(Element node)	Pretty prints an XML document to a string, starting from the specified element.
static void	prettyPrint(Element node, Writer wrt)	Pretty prints an XML document to a writer, starting from the specified element.
static void	setSetting(Element parentNode, String settingName, String settingValue)	Sets the value of a a "setting" element.
static void	setStringValue(Element element, String value)	Sets the text value as a text node child of a an element.
static void	storeDocumentToFile(Document doc, File file)	Stores an XML document in a file.
static String	storeDocumentToString(Document doc)	Stores an XML document as a string.

Methods inherited from class java.lang.Object

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

Method Detail

getOrCreateElement

public static Element getOrCreateElement(Element parentNode,
                                         String tagName)

Returns the child element with the specified tag name of the specified parent node. If no such child element is found, a new element with the specified tag name is created and returned.

Parameters:

parentNode - parent node for the wanted element

tagName - name of the wanted element

Returns:

the child element

See Also:

getChildElementOrNull(Element, String)

createElement

public static Element createElement(Element parentNode,
                                    String tagName)

Adds a child element with the name tagName to the parent and returns the new child element.

Parameters:

parentNode - parent node to add the new element to

tagName - the name of the new child element

Returns:

the new child element

setSetting

public static void setSetting(Element parentNode,
                              String settingName,
                              String settingValue)

Sets the value of a a "setting" element. If it already exists it will be updated. If it does not exist it will be created. If the setting element already exists, then there must not be any child elements to it other than a text value.

Parameters:

parentNode - parent node of the setting element

settingName - tag name of the setting element

settingValue - the value to set

createNewDocument

public static Document createNewDocument(String rootElementName)
                                  throws IOException

Creates a new empty XML document.

Parameters:

rootElementName - the name of the root element

Returns:

an empty document

Throws:

IOException - if there is a problem creating the XML document

createSAXParserFactory

public static SAXParserFactory createSAXParserFactory()
                                               throws SAXNotRecognizedException,
                                                      SAXNotSupportedException,
                                                      ParserConfigurationException

Create a SAX parser factory with safe settings.

See OWASP XXE cheat sheet.

Returns:

a new SAX parser factory

Throws:

SAXNotRecognizedException

SAXNotSupportedException

ParserConfigurationException

createDocumentBuildFactoryInstance

public static DocumentBuilderFactory createDocumentBuildFactoryInstance()
                                                                 throws ParserConfigurationException

Create a document builder factory with safe settings.

See OWASP XXE cheat sheet.

Returns:

a new document builder factory

Throws:

ParserConfigurationException

createTransformerFactory

public static TransformerFactory createTransformerFactory()
                                                   throws TransformerFactoryConfigurationError,
                                                          TransformerConfigurationException

Create a transformer factory with safe settings.

See OWASP XXE cheat sheet.

Returns:

a new transformer factory

Throws:

TransformerFactoryConfigurationError

TransformerConfigurationException

setStringValue

public static void setStringValue(Element element,
                                  String value)

Sets the text value as a text node child of a an element. The element must not have any other child elements.

Parameters:

element - the element to set the text value for

value - the new value to set

getSetting

public static String getSetting(Element parent,
                                String settingName,
                                String defaultValue)

Returns the value of the setting with the specified name or a default value if the setting had no value.

Since everything should have a default value, no other version of get setting exists. This method implicitly builds the setting node with a default value if none is found.

Parameters:

parent - the parent element whose children to search for the settings node.

settingName - name of the setting

defaultValue - default value to return if setting is empty

Returns:

see above.

getStringValue

public static String getStringValue(Element element)

Returns the content between the tags of the element, for example <tag>hello </tag> where the value is "hello". If the element itself or its child is null, null will be returned. This method will only return a non-null String if the child node of the element is a text node.

Parameters:

element - the element from which to extract the text node.

Returns:

the String value of the text node.

prettyPrint

public static String prettyPrint(Element node)

Pretty prints an XML document to a string, starting from the specified element.

Parameters:

node - node from which to start pretty printing

Returns:

a string containing the pretty printed document

prettyPrint

public static void prettyPrint(Element node,
                               Writer wrt)

Pretty prints an XML document to a writer, starting from the specified element.

Parameters:

node - node from which to start pretty printing

wrt - writer to write the document to

getChildElementsByTag

public static List<Element> getChildElementsByTag(Node contextNode,
                                                  String tag)

Returns all the children from a node with a tag matching the tag argument.

Parameters:

contextNode - node whose children to search

tag - the tag to search for

Returns:

A list of elements with the found nodes. Will return an empty list if no matching element could be found.

loadDocumentFromFile

public static Document loadDocumentFromFile(File file)
                                     throws SAXException,
                                            IOException

Loads an XML document from the specified file.

Parameters:

file - the file from which to read the document

Returns:

the parsed XML document

Throws:

SAXException - if the document could not be parsed

IOException - if the stream could not be read

loadDocumentFromStream

public static Document loadDocumentFromStream(InputStream stream)
                                       throws SAXException,
                                              IOException

Loads an XML document from the specified stream.

Parameters:

stream - the input stream from which to read the document

Returns:

the parsed XML document

Throws:

SAXException - if the document could not be parsed

IOException - if the stream could not be read

loadDocumentFromString

public static Document loadDocumentFromString(String doc)
                                       throws SAXException

Loads an XML document from its string representation.

Parameters:

doc - the string to read from

Returns:

the parsed XML document

Throws:

SAXException - if the document could not be parsed

NullPointerException - if the input string is null

storeDocumentToFile

public static void storeDocumentToFile(Document doc,
                                       File file)
                                throws IOException

Stores an XML document in a file.

Parameters:

doc - the XML document to store

file - the file to store it in

Throws:

IOException - if the file could not written

storeDocumentToString

public static String storeDocumentToString(Document doc)

Stores an XML document as a string.

Parameters:

doc - the XML document to store

Returns:

the XML document as a string

getChildElementOrNull

public static Element getChildElementOrNull(Element parent,
                                            String name)

Returns the child element with the specified tag name of the specified parent node. If no such child element is found, null is returned.

Parameters:

parent - parent node for the wanted element

name - name of the wanted element

Returns:

the child element, or null if no such element exists

See Also:

getOrCreateElement(Element, String)

escapeAll

public static String escapeAll(String s)

escapeTagContent

public static String escapeTagContent(String s)