org.apache.hadoop.hdfs.util

Class XMLUtils

java.lang.Object

org.apache.hadoop.hdfs.util.XMLUtils

@InterfaceAudience.Private
@InterfaceStability.Unstable
public class XMLUtils
extends Object

General xml utilities.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	XMLUtils.InvalidXmlException Exception that reflects an invalid XML document.
static class	XMLUtils.Stanza Represents a bag of key-value pairs encountered during parsing an XML file.
static class	XMLUtils.UnmanglingError Exception that reflects a string that cannot be unmangled.

Constructor Summary

Constructors

Constructor and Description
XMLUtils()

Method Summary

Methods

Modifier and Type	Method and Description
static void	addSaxString(ContentHandler contentHandler, String tag, String val) Add a SAX tag with a string inside.
static String	mangleXmlString(String str) Mangle a string so that it can be represented in an XML document.
static String	unmangleXmlString(String str) Demangle a string from an XML document.

Methods inherited from class java.lang.Object

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

Constructor Detail

XMLUtils

public XMLUtils()

Method Detail

mangleXmlString

public static String mangleXmlString(String str)

Mangle a string so that it can be represented in an XML document. There are three kinds of code points in XML: - Those that can be represented normally, - Those that have to be escaped (for example, & must be represented as &) - Those that cannot be represented at all in XML. The built-in SAX functions will handle the first two types for us just fine. However, sometimes we come across a code point of the third type. In this case, we have to mangle the string in order to represent it at all. We also mangle backslash to avoid confusing a backslash in the string with part our escape sequence. The encoding used here is as follows: an illegal code point is represented as '\ABCD;', where ABCD is the hexadecimal value of the code point.

Parameters:

str - The input string.

Returns:

The mangled string.

unmangleXmlString

public static String unmangleXmlString(String str)
                                throws XMLUtils.UnmanglingError

Demangle a string from an XML document. See mangleXmlString(String) for a description of the mangling format.

Parameters:

str - The string to be demangled.

Returns:

The unmangled string

Throws:

XMLUtils.UnmanglingError - if the input is malformed.

addSaxString

public static void addSaxString(ContentHandler contentHandler,
                String tag,
                String val)
                         throws SAXException

Add a SAX tag with a string inside.

Parameters:

contentHandler - the SAX content handler

tag - the element tag to use

value - the string to put inside the tag

Throws:

SAXException