OpenJDK 27 · com.sun.org.apache.xpath.internal.VariableStack

Modifier and Type	Field and Description
private int	_currentFrameBottom The bottom index of the current frame (relative to `_stackFrames`).
pack-priv int	_frameTop The top of the stack frame (`_stackFrames`).
pack-priv int[]	_links The stack of frame positions.
pack-priv int	_linksTop The top of the links stack.
pack-priv XObject[]	_stackFrames The stack frame where all variables and params will be kept.
public static final int	CLEARLIMITATION limitation for 1K
private static XObject[]	m_nulls NEEDSDOC Field m_nulls

Access	Constructor and Description
public	VariableStack() Constructor for a variable stack.

Method Summary

Modifier and Type	Method and Description
public void	clearLocalSlots(int The start position, relative to the current local stack frame. start, int The number of slots to be cleared. len) Use this to clear the variables in a section of the stack.
public synchronized Object	Returns: a clone of this variable stack. clone() Overrides java.lang.Object.clone. Returns a clone of this variable stack.
public XObject	Returns: The item at the given index. elementAt(final int index from zero. i) Get the element at the given index, regardless of stackframe.
public XObject	Returns: The value of the variable. getGlobalVariable(XPathContext The XPath context, which must be passed in order to lazy evaluate variables. xctxt, final int Global variable index relative to the global stack frame bottom. index) Get a global variable or parameter from the global stack frame.
public XObject	Returns: The value of the variable. getGlobalVariable(XPathContext The XPath context, which must be passed in order to lazy evaluate variables. xctxt, final int Global variable index relative to the global stack frame bottom. index, boolean destructiveOK) Get a global variable or parameter from the global stack frame.
public XObject	Returns: The value of the variable. getLocalVariable(XPathContext The XPath context, which must be passed in order to lazy evaluate variables. xctxt, int Local variable index relative to the current stack frame bottom. index) Get a local variable or parameter in the current stack frame.
public XObject	Returns: The value of the variable. getLocalVariable(int Local variable index relative to the given frame bottom. NEEDSDOC @param frame index, int frame) Get a local variable or parameter in the current stack frame.
public XObject	Returns: The value of the variable. getLocalVariable(XPathContext The XPath context, which must be passed in order to lazy evaluate variables. xctxt, int Local variable index relative to the current stack frame bottom. index, boolean destructiveOK) Get a local variable or parameter in the current stack frame.
public int	Returns: The current stack frame position. getStackFrame() Get the position from where the search should start, which is either the searchStart property, or the top of the stack if that value is -1.
public XObject	Returns: The evaluated value of the variable. getVariableOrParam(XPathContext The XPath context, which must be passed in order to lazy evaluate variables. xctxt, QName The qualified name of the variable. qname) Get a variable based on it's qualified name.
public boolean	Returns: true if the value at the index is not null. isLocalSet(int Local variable index relative to the current stack frame bottom. index) Tell if a local variable has been set or not.
public int	Returns: The bottom of the stack frame, from where local variable addressing should start from. link(final int The size of the stack frame allocation. This ammount should normally be the maximum number of variables that you can have allocated at one time in the new stack frame. size) Allocates memory (called a stackframe) on the stack; used to store local variables and parameter arguments.
public void	Returns: the total size of the execution stack. reset() Reset the stack to a start position.
public void	setGlobalVariable(final int Local variable index relative to the global stack frame bottom. index, final XObject The value of the variable that is being set. val) Set a global variable or parameter in the global stack frame.
public void	setLocalVariable(int Local variable index relative to the current stack frame bottom. index, XObject The value of the variable that is being set. val) Set a local variable or parameter in the current stack frame.
public void	setLocalVariable(int Local variable index relative to the current stack frame bottom. NEEDSDOC @param stackFrame index, XObject The value of the variable that is being set. val, int stackFrame) Set a local variable or parameter in the specified stack frame.
public void	setStackFrame(int The new stack frame position. sf) Set the current stack frame.
public int	Returns: the total size of the execution stack. size() Get size of the stack.
public void	unlink() Free up the stack frame that was last allocated with `link(int size)`.
public void	unlink(int The current frame to set to after the unlink. currentFrame) Free up the stack frame that was last allocated with `link(int size)`.

Inherited from java.lang.Object:: equals finalize getClass hashCode notify notifyAll toString wait wait wait

_currentFrameBottom	back to summary
private int _currentFrameBottom The bottom index of the current frame (relative to `_stackFrames`).

_frameTop	back to summary
pack-priv int _frameTop The top of the stack frame (`_stackFrames`).

_links	back to summary
pack-priv int[] _links The stack of frame positions. I call 'em links because of distant Motorola 68000 assembler memories. :-)

_linksTop	back to summary
pack-priv int _linksTop The top of the links stack.

_stackFrames	back to summary
pack-priv XObject[] _stackFrames The stack frame where all variables and params will be kept.

CLEARLIMITATION	back to summary
public static final int CLEARLIMITATION limitation for 1K

m_nulls	back to summary
private static XObject[] m_nulls NEEDSDOC Field m_nulls

VariableStack	back to summary
public VariableStack() Constructor for a variable stack.

Method Detail

clearLocalSlots	back to summary
public void clearLocalSlots(int start, int len) Use this to clear the variables in a section of the stack. This is used to clear the parameter section of the stack, so that default param values can tell if they've already been set. It is important to note that this function has a 1K limitation. Parameters start:int The start position, relative to the current local stack frame. len:int The number of slots to be cleared.

clearLocalSlots

back to summary

public void clearLocalSlots(int start, int len)

Use this to clear the variables in a section of the stack. This is used to clear the parameter section of the stack, so that default param values can tell if they've already been set. It is important to note that this function has a 1K limitation.

Parameters

start:int: The start position, relative to the current local stack frame.
len:int: The number of slots to be cleared.

clone back to summary

clone	back to summary
public synchronized Object clone() throws CloneNotSupportedException Overrides java.lang.Object.clone. Returns a clone of this variable stack. Returns:Object a clone of this variable stack. Exceptions CloneNotSupportedException: Doc from java.lang.Object.clone. if the object's class does not support the `Cloneable` interface. Subclasses that override the `clone` method can also throw this exception to indicate that an instance cannot be cloned.

public synchronized Object clone() throws CloneNotSupportedException

Overrides java.lang.Object.clone.

Returns a clone of this variable stack.

Returns:Object

a clone of this variable stack.

Exceptions

CloneNotSupportedException:

Doc from java.lang.Object.clone.

if the object's class does not support the Cloneable interface. Subclasses that override the clone method can also throw this exception to indicate that an instance cannot be cloned.

elementAt	back to summary
public XObject elementAt(final int i) Get the element at the given index, regardless of stackframe. Parameters i:int index from zero. Returns:XObject The item at the given index.

elementAt

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public XObject elementAt(final int i)

Get the element at the given index, regardless of stackframe.

Parameters

i:int: index from zero.

Returns:XObject

The item at the given index.

getGlobalVariable	back to summary
public XObject getGlobalVariable(XPathContext xctxt, final int index) throws TransformerException Get a global variable or parameter from the global stack frame. Parameters xctxt:XPathContext The XPath context, which must be passed in order to lazy evaluate variables. index:int Global variable index relative to the global stack frame bottom. Returns:XObject The value of the variable.

getGlobalVariable

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public XObject getGlobalVariable(XPathContext xctxt, final int index) throws TransformerException

Get a global variable or parameter from the global stack frame.

Parameters

xctxt:XPathContext: The XPath context, which must be passed in order to lazy evaluate variables.
index:int: Global variable index relative to the global stack frame bottom.

Returns:XObject

The value of the variable.

getGlobalVariable	back to summary
public XObject getGlobalVariable(XPathContext xctxt, final int index, boolean destructiveOK) throws TransformerException Get a global variable or parameter from the global stack frame. Parameters xctxt:XPathContext The XPath context, which must be passed in order to lazy evaluate variables. index:int Global variable index relative to the global stack frame bottom. Returns:XObject The value of the variable.

getGlobalVariable

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public XObject getGlobalVariable(XPathContext xctxt, final int index, boolean destructiveOK) throws TransformerException

Get a global variable or parameter from the global stack frame.

Parameters

xctxt:XPathContext: The XPath context, which must be passed in order to lazy evaluate variables.
index:int: Global variable index relative to the global stack frame bottom.

Returns:XObject

The value of the variable.

getLocalVariable	back to summary
public XObject getLocalVariable(XPathContext xctxt, int index) throws TransformerException Get a local variable or parameter in the current stack frame. Parameters xctxt:XPathContext The XPath context, which must be passed in order to lazy evaluate variables. index:int Local variable index relative to the current stack frame bottom. Returns:XObject The value of the variable.

getLocalVariable

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public XObject getLocalVariable(XPathContext xctxt, int index) throws TransformerException

Get a local variable or parameter in the current stack frame.

Parameters

xctxt:XPathContext: The XPath context, which must be passed in order to lazy evaluate variables.
index:int: Local variable index relative to the current stack frame bottom.

Returns:XObject

The value of the variable.

getLocalVariable	back to summary
public XObject getLocalVariable(int index, int frame) throws TransformerException Get a local variable or parameter in the current stack frame. Parameters index:int Local variable index relative to the given frame bottom. NEEDSDOC @param frame Returns:XObject The value of the variable.

getLocalVariable

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public XObject getLocalVariable(int index, int frame) throws TransformerException

Get a local variable or parameter in the current stack frame.

Parameters

index:int: Local variable index relative to the given frame bottom. NEEDSDOC @param frame

Returns:XObject

The value of the variable.

getLocalVariable	back to summary
public XObject getLocalVariable(XPathContext xctxt, int index, boolean destructiveOK) throws TransformerException Get a local variable or parameter in the current stack frame. Parameters xctxt:XPathContext The XPath context, which must be passed in order to lazy evaluate variables. index:int Local variable index relative to the current stack frame bottom. Returns:XObject The value of the variable.

getLocalVariable

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public XObject getLocalVariable(XPathContext xctxt, int index, boolean destructiveOK) throws TransformerException

Get a local variable or parameter in the current stack frame.

Parameters

xctxt:XPathContext: The XPath context, which must be passed in order to lazy evaluate variables.
index:int: Local variable index relative to the current stack frame bottom.

Returns:XObject

The value of the variable.

getStackFrame	back to summary
public int getStackFrame() Get the position from where the search should start, which is either the searchStart property, or the top of the stack if that value is -1. Returns:int The current stack frame position.

getStackFrame

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public int getStackFrame()

Get the position from where the search should start, which is either the searchStart property, or the top of the stack if that value is -1.

Returns:int: The current stack frame position.

getVariableOrParam	back to summary
public XObject getVariableOrParam(XPathContext xctxt, QName qname) throws TransformerException Get a variable based on it's qualified name. This is for external use only. Parameters xctxt:XPathContext The XPath context, which must be passed in order to lazy evaluate variables. qname:QName The qualified name of the variable. Returns:XObject The evaluated value of the variable.

getVariableOrParam

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public XObject getVariableOrParam(XPathContext xctxt, QName qname) throws TransformerException

Get a variable based on it's qualified name. This is for external use only.

Parameters

xctxt:XPathContext: The XPath context, which must be passed in order to lazy evaluate variables.
qname:QName: The qualified name of the variable.

Returns:XObject

The evaluated value of the variable.

isLocalSet	back to summary
public boolean isLocalSet(int index) throws TransformerException Tell if a local variable has been set or not. Parameters index:int Local variable index relative to the current stack frame bottom. Returns:boolean true if the value at the index is not null.

isLocalSet

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public boolean isLocalSet(int index) throws TransformerException

Tell if a local variable has been set or not.

Parameters

index:int: Local variable index relative to the current stack frame bottom.

Returns:boolean

true if the value at the index is not null.

link	back to summary
public int link(final int size) Allocates memory (called a stackframe) on the stack; used to store local variables and parameter arguments. I use the link/unlink concept because of distant Motorola 68000 assembler memories. Parameters size:int The size of the stack frame allocation. This ammount should normally be the maximum number of variables that you can have allocated at one time in the new stack frame. Returns:int The bottom of the stack frame, from where local variable addressing should start from.

link

back to summary

public int link(final int size)

Allocates memory (called a stackframe) on the stack; used to store local variables and parameter arguments.

I use the link/unlink concept because of distant Motorola 68000 assembler memories.

Parameters

size:int: The size of the stack frame allocation. This ammount should normally be the maximum number of variables that you can have allocated at one time in the new stack frame.

Returns:int

The bottom of the stack frame, from where local variable addressing should start from.

reset	back to summary
public void reset() Reset the stack to a start position. Returns:void the total size of the execution stack.

reset

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public void reset()

Reset the stack to a start position.

Returns:void: the total size of the execution stack.

setGlobalVariable	back to summary
public void setGlobalVariable(final int index, final XObject val) Set a global variable or parameter in the global stack frame. Parameters index:int Local variable index relative to the global stack frame bottom. val:XObject The value of the variable that is being set.

setGlobalVariable

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public void setGlobalVariable(final int index, final XObject val)

Set a global variable or parameter in the global stack frame.

Parameters

index:int: Local variable index relative to the global stack frame bottom.
val:XObject: The value of the variable that is being set.

setLocalVariable	back to summary
public void setLocalVariable(int index, XObject val) Set a local variable or parameter in the current stack frame. Parameters index:int Local variable index relative to the current stack frame bottom. val:XObject The value of the variable that is being set.

setLocalVariable

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public void setLocalVariable(int index, XObject val)

Set a local variable or parameter in the current stack frame.

Parameters

index:int: Local variable index relative to the current stack frame bottom.
val:XObject: The value of the variable that is being set.

setLocalVariable	back to summary
public void setLocalVariable(int index, XObject val, int stackFrame) Set a local variable or parameter in the specified stack frame. Parameters index:int Local variable index relative to the current stack frame bottom. NEEDSDOC @param stackFrame val:XObject The value of the variable that is being set.

setLocalVariable

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public void setLocalVariable(int index, XObject val, int stackFrame)

Set a local variable or parameter in the specified stack frame.

Parameters

index:int: Local variable index relative to the current stack frame bottom. NEEDSDOC @param stackFrame
val:XObject: The value of the variable that is being set.

setStackFrame	back to summary
public void setStackFrame(int sf) Set the current stack frame. Parameters sf:int The new stack frame position.

setStackFrame

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public void setStackFrame(int sf)

Set the current stack frame.

Parameters

sf:int: The new stack frame position.

size	back to summary
public int size() Get size of the stack. Returns:int the total size of the execution stack.

size

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public int size()

Get size of the stack.

Returns:int: the total size of the execution stack.

unlink	back to summary
public void unlink() Free up the stack frame that was last allocated with `link(int size)`.

unlink back to summary

unlink	back to summary
public void unlink(int currentFrame) Free up the stack frame that was last allocated with `link(int size)`. Parameters currentFrame:int The current frame to set to after the unlink.

public void unlink(int currentFrame)

Free up the stack frame that was last allocated with link(int size).

Parameters

currentFrame:int: The current frame to set to after the unlink.

public Class VariableStack

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail