org.apache.drill.exec.store.xml

Class XMLUtils

java.lang.Object

org.apache.drill.exec.store.xml.XMLUtils

public class XMLUtils
extends Object

Constructor Summary

Constructors

Constructor and Description
XMLUtils()

Method Summary

Modifier and Type	Method and Description
static String	addField(String prefix, String field) Generates a nested field name by combining a field prefix to the current field name.
static boolean	hasAttributes(XMLEvent event) Returns true if a given XMLEvent has attributes, false if not.
static boolean	isEmptyWhiteSpace(XMLEvent event) Empty events are not helpful so this method checks to see if the event consists solely of whitespace or newline characters.
static boolean	isNotCruft(XMLEvent event) Identifies XML events that may be populated but are not useful for extracting data.
static String	removeField(String prefix, String fieldName) Returns the field name from nested field names.

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

isEmptyWhiteSpace

public static boolean isEmptyWhiteSpace(XMLEvent event)

Empty events are not helpful so this method checks to see if the event consists solely of whitespace or newline characters. Unfortunately, newlines and other extraneous characters are treated as new elements, so this function wraps a lot of those checks in one function.

Parameters:

event - The input XMLEvent

Returns:

True if the XMLEvent is only whitespace, false if not.

isNotCruft

public static boolean isNotCruft(XMLEvent event)

Identifies XML events that may be populated but are not useful for extracting data.

Parameters:

event - The XMLEvent in question

Returns:

True if the event is useful, false if not

addField

public static String addField(String prefix,
                              String field)

Generates a nested field name by combining a field prefix to the current field name.

Parameters:

prefix - The prefix to be added to the field name.

field - The field name

Returns:

the prefix, followed by an underscore and the fieldname.

removeField

public static String removeField(String prefix,
                                 String fieldName)

Returns the field name from nested field names.

Parameters:

fieldName - The nested field name

Returns:

The field name

hasAttributes

public static boolean hasAttributes(XMLEvent event)

Returns true if a given XMLEvent has attributes, false if not. Since only start elements can by definition have attributes, returns false if the event is not a start element.

Parameters:

event - The XMLEvent in question

Returns:

True if the XMLEvent has attributes, false if not.