com.ctc.wstx.io

Class WstxInputSource

java.lang.Object

com.ctc.wstx.io.WstxInputSource

Direct Known Subclasses:

BaseInputSource

public abstract class WstxInputSource
extends Object

Interface that defines API actual parsers (stream readers) can use to read input from various input sources. Needed to abstract out details of getting input from primary input files, secondary (potentially cached) referenced documents, and from parsed entities, as well as for allowing hierarchic location information for error reporting.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	mEntityDepth Number of parent entities that have been expanded to get to this input source; 0 for root-level input that is not generated via entity expansion.
protected String	mFromEntity Name/id of the entity that was expanded to produce this input source; null if not entity-originated.
protected WstxInputSource	mParent Parent in input source stack
protected int	mScopeId Scope of the reader when this entity was initially expanded.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	WstxInputSource(WstxInputSource parent, String fromEntity)

Method Summary

Methods

Modifier and Type	Method and Description
abstract void	close() Method reader calls for this input source when it has encountered EOF.
abstract void	closeCompletely() Method reader MAY call to force full closing of the underlying input stream(s)/reader(s).
protected abstract void	doInitInputLocation(WstxInputData reader)
abstract boolean	fromInternalEntity()
int	getEntityDepth()
String	getEntityId()
protected abstract WstxInputLocation	getLocation() Method usually called to get a parent location for another input source.
abstract WstxInputLocation	getLocation(long total, int row, int col)
WstxInputSource	getParent()
abstract String	getPublicId()
int	getScopeId()
abstract URL	getSource()
abstract String	getSystemId()
void	initInputLocation(WstxInputData reader, int currScopeId, int entityDepth) Method called by Reader when current input has changed to come from this input source.
boolean	isOrIsExpandedFrom(String entityId) Method that checks if this input source expanded from the specified entity id, directly or by ancestor.
abstract void	overrideSource(URL url) Method that can be called to override originally defined source.
abstract int	readInto(WstxInputData reader) Method called to read at least one more char from input source, and update input data appropriately.
abstract boolean	readMore(WstxInputData reader, int minAmount) Method called by reader when it has to have at least specified number of consequtive input characters in its buffer, and it currently does not have.
abstract void	restoreContext(WstxInputData reader) Method Reader calls when this input source is resumed as the current source.
abstract void	saveContext(WstxInputData reader) Method Reader calls when this input source is being stored, when a nested input source gets used instead (due to entity expansion).
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

mParent

protected final WstxInputSource mParent

Parent in input source stack

mFromEntity

protected final String mFromEntity

Name/id of the entity that was expanded to produce this input source; null if not entity-originated. Used for catching recursive expansions of entities.

mScopeId

protected int mScopeId

Scope of the reader when this entity was initially expanded. Snapshot that will generally be used by the reader to match scoping limitations, such as proper nesting entity expansion with respect to element and declaration nesting.

mEntityDepth

protected int mEntityDepth

Number of parent entities that have been expanded to get to this input source; 0 for root-level input that is not generated via entity expansion.

Constructor Detail

WstxInputSource

protected WstxInputSource(WstxInputSource parent,
               String fromEntity)

Method Detail

overrideSource

public abstract void overrideSource(URL url)

Method that can be called to override originally defined source.

Parameters:

url - New base URL to set; may be null.

Since:

4.0

getParent

public final WstxInputSource getParent()

isOrIsExpandedFrom

public boolean isOrIsExpandedFrom(String entityId)

Method that checks if this input source expanded from the specified entity id, directly or by ancestor.

Note that entity ids are expected to have been interned (using whatever uniqueness mechanism used), and thus can be simply identity checked.

fromInternalEntity

public abstract boolean fromInternalEntity()

Returns:

True, if this input source was directly expanded from an internal entity (general, parsed); false if not (from external entity, DTD ext. subset, main document)

getSource

public abstract URL getSource()
                       throws IOException

Throws:

IOException

getPublicId

public abstract String getPublicId()

getSystemId

public abstract String getSystemId()

getLocation

protected abstract WstxInputLocation getLocation()

Method usually called to get a parent location for another input source. Works since at this point context (line, row, chars) information has already been saved to this object.

getLocation

public abstract WstxInputLocation getLocation(long total,
                            int row,
                            int col)

getEntityId

public String getEntityId()

getScopeId

public int getScopeId()

getEntityDepth

public int getEntityDepth()

initInputLocation

public final void initInputLocation(WstxInputData reader,
                     int currScopeId,
                     int entityDepth)

Method called by Reader when current input has changed to come from this input source. Should reset/initialize input location information Reader keeps, for error messages to work ok.

Parameters:

reader - Reader whose data structures are to be used for returning data read

currScopeId -

doInitInputLocation

protected abstract void doInitInputLocation(WstxInputData reader)

readInto

public abstract int readInto(WstxInputData reader)
                      throws IOException,
                             XMLStreamException

Method called to read at least one more char from input source, and update input data appropriately.

Returns:

Number of characters read from the input source (at least 1), if it had any input; -1 if input source has no more input.

Throws:

IOException

XMLStreamException

readMore

public abstract boolean readMore(WstxInputData reader,
               int minAmount)
                          throws IOException,
                                 XMLStreamException

Method called by reader when it has to have at least specified number of consequtive input characters in its buffer, and it currently does not have. If so, it asks input source to do whatever it has to do to try to get more data, if possible (including moving stuff in input buffer if necessary and possible).

Returns:

True if input source was able to provide specific number of characters or more; false if not. In latter case, source is free to return zero or more characters any way.

Throws:

IOException

XMLStreamException

saveContext

public abstract void saveContext(WstxInputData reader)

Method Reader calls when this input source is being stored, when a nested input source gets used instead (due to entity expansion). Needs to get location info from Reader and store it in this Object.

restoreContext

public abstract void restoreContext(WstxInputData reader)

Method Reader calls when this input source is resumed as the current source. Needs to update Reader's input location data used for error messages etc.

close

public abstract void close()
                    throws IOException

Method reader calls for this input source when it has encountered EOF. This may or may not close the underlying stream/reader; what happens depends on configuration

Throws:

IOException

closeCompletely

public abstract void closeCompletely()
                              throws IOException

Method reader MAY call to force full closing of the underlying input stream(s)/reader(s). No checks are done regarding configuration, but input source object is to deal gracefully with multiple calls (ie. it's not an error for reader to call this more than once).

Throws:

IOException

toString

public String toString()

Overrides:

toString in class Object