com.caucho.xpath

Class Expr

java.lang.Object

com.caucho.xpath.Expr

Direct Known Subclasses:

AbstractNumberExpr, AbstractStringExpr, BooleanExpr, FunExpr, IdExpr, NewJavaExpr, NodeSetExpr, NumericExpr, ObjectExpr, ObjectJavaExpr, StaticJavaExpr, StringExpr, VarExpr

public abstract class Expr
extends java.lang.Object

Compute values from nodes. Because the expressions themselves are untyped, the class provides methods for creating the type of the desired result.

Field Summary

Fields

Modifier and Type	Field and Description
protected static int	ADD
protected static int	AND
protected static int	ATTRIBUTE
protected static int	BASE_URI
protected static int	BOOLEAN
protected static int	BOOLEAN_EQ
protected static int	BOOLEAN_NEQ
protected static int	CEILING
protected static int	CONCAT
protected static int	CONST
protected static int	CONTAINS
protected static int	COUNT
protected static int	DIV
protected static int	ELEMENT
protected static int	EQ
protected static int	FALSE
protected static int	FLOOR
protected static int	FORMAT_NUMBER
protected static int	FUNCTION_AVAILABLE
protected static int	GE
protected static int	GENERATE_ID
protected static int	GT
protected static int	ID
protected static int	IF
protected static int	LANG
protected static int	LAST
protected static int	LAST_FUN
protected static int	LE
protected static int	LOCAL_PART
protected static int	LT
protected static int	MOD
protected static int	MUL
protected static int	NAMESPACE
protected static int	NEG
protected static int	NEQ
protected static int	NODE_SET
protected static int	NORMALIZE
protected static int	NOT
protected static int	NUMBER
protected static int	NUMBER_EQ
protected static int	NUMBER_GE
protected static int	NUMBER_GT
protected static int	NUMBER_LE
protected static int	NUMBER_LT
protected static int	NUMBER_NEQ
protected static int	OR
static int	POSITION
protected static int	QNAME
protected static int	QUO
protected static int	ROUND
protected static int	SELF
protected static int	SELF_NAME
protected static int	STARTS_WITH
protected static int	STRING
protected static int	STRING_EQ
protected static int	STRING_LENGTH
protected static int	STRING_NEQ
protected static int	SUB
protected static int	SUBSTRING
protected static int	SUBSTRING_AFTER
protected static int	SUBSTRING_BEFORE
protected static int	SUM
protected static int	SYSTEM_PROPERTY
protected static int	TRANSLATE
protected static int	TRUE

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Expr()

Method Summary

Modifier and Type	Method and Description
void	addParam(Env newEnv, java.lang.String name, org.w3c.dom.Node node, Env env) Adds a param with the expression's value.
void	addVar(Env newEnv, java.lang.String name, org.w3c.dom.Node node, Env env) Adds a variable with the expression's value.
boolean	evalBoolean(org.w3c.dom.Node node) Returns the boolean value of the node.
abstract boolean	evalBoolean(org.w3c.dom.Node node, ExprEnvironment env) Returns the boolean value of the node.
NodeIterator	evalNodeSet(org.w3c.dom.Node node) Returns an iterator of matching nodes
NodeIterator	evalNodeSet(org.w3c.dom.Node node, ExprEnvironment env) Returns an iterator of matching nodes
double	evalNumber(org.w3c.dom.Node node) Evaluates the expression as a double using the node as a context.
abstract double	evalNumber(org.w3c.dom.Node node, ExprEnvironment env) Evaluates the expression as a number.
java.lang.Object	evalObject(org.w3c.dom.Node node) Returns the object value of the node.
abstract java.lang.Object	evalObject(org.w3c.dom.Node node, ExprEnvironment env) Returns the object value of the node.
void	evalString(CharBuffer cb, org.w3c.dom.Node node) Fills a char buffer with the evaluated string results.
void	evalString(CharBuffer cb, org.w3c.dom.Node node, ExprEnvironment env) Fills a char buffer with the evaluated string results.
java.lang.String	evalString(org.w3c.dom.Node node) Returns the expression evaluated as a string.
abstract java.lang.String	evalString(org.w3c.dom.Node node, ExprEnvironment env) Returns the string value of the node.
Var	evalVar(org.w3c.dom.Node node, ExprEnvironment env) Evaluates to a variable.
AbstractPattern	getListContext()
boolean	isBoolean() true if the expression prefers to return a boolean.
boolean	isNodeSet() true if the expression prefers to return a node set.
boolean	isNumber() true if the expression prefers to return a number.
boolean	isString() true if the expression prefers to return a string.
void	setListContext(AbstractPattern listContext)
void	setVar(java.lang.String name, org.w3c.dom.Node node, Env env) Sets a variable with the expression's value.
protected static double	stringToNumber(java.lang.String string) Convert a string to a double following XPath.
static boolean	toBoolean(java.lang.Object value) Convert a Java object to a boolean using the XPath rules.
static double	toDouble(java.lang.Object value) Convert a Java object to a double using the XPath rules.
static org.w3c.dom.Node	toNode(java.lang.Object value) Convert a Java object to a node using the XPath rules.
protected AbstractPattern	toNodeList() Convert from an expression to a pattern.
static java.lang.String	toString(java.lang.Object value) Convert a Java object to a string using the XPath rules.

Methods inherited from class java.lang.Object

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

Field Detail

CONST

protected static final int CONST

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Constant Field Values

NODE_SET

protected static final int NODE_SET

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Constant Field Values

ID

protected static final int ID

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OR

protected static final int OR

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AND

protected static final int AND

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EQ

protected static final int EQ

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NEQ

protected static final int NEQ

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LT

protected static final int LT

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LE

protected static final int LE

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GT

protected static final int GT

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GE

protected static final int GE

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BOOLEAN_EQ

protected static final int BOOLEAN_EQ

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BOOLEAN_NEQ

protected static final int BOOLEAN_NEQ

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NUMBER_EQ

protected static final int NUMBER_EQ

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NUMBER_NEQ

protected static final int NUMBER_NEQ

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NUMBER_LT

protected static final int NUMBER_LT

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NUMBER_LE

protected static final int NUMBER_LE

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NUMBER_GT

protected static final int NUMBER_GT

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NUMBER_GE

protected static final int NUMBER_GE

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STRING_EQ

protected static final int STRING_EQ

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STRING_NEQ

protected static final int STRING_NEQ

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NEG

protected static final int NEG

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ADD

protected static final int ADD

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SUB

protected static final int SUB

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MUL

protected static final int MUL

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DIV

protected static final int DIV

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QUO

protected static final int QUO

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MOD

protected static final int MOD

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TRUE

protected static final int TRUE

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FALSE

protected static final int FALSE

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NOT

protected static final int NOT

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BOOLEAN

protected static final int BOOLEAN

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LANG

protected static final int LANG

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NUMBER

protected static final int NUMBER

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SUM

protected static final int SUM

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FLOOR

protected static final int FLOOR

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CEILING

protected static final int CEILING

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ROUND

protected static final int ROUND

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POSITION

public static final int POSITION

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COUNT

protected static final int COUNT

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LAST

protected static final int LAST

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STRING

protected static final int STRING

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CONCAT

protected static final int CONCAT

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STARTS_WITH

protected static final int STARTS_WITH

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CONTAINS

protected static final int CONTAINS

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SUBSTRING

protected static final int SUBSTRING

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SUBSTRING_BEFORE

protected static final int SUBSTRING_BEFORE

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SUBSTRING_AFTER

protected static final int SUBSTRING_AFTER

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STRING_LENGTH

protected static final int STRING_LENGTH

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NORMALIZE

protected static final int NORMALIZE

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TRANSLATE

protected static final int TRANSLATE

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FORMAT_NUMBER

protected static final int FORMAT_NUMBER

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LOCAL_PART

protected static final int LOCAL_PART

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NAMESPACE

protected static final int NAMESPACE

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QNAME

protected static final int QNAME

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GENERATE_ID

protected static final int GENERATE_ID

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FUNCTION_AVAILABLE

protected static final int FUNCTION_AVAILABLE

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SYSTEM_PROPERTY

protected static final int SYSTEM_PROPERTY

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IF

protected static final int IF

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SELF

protected static final int SELF

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SELF_NAME

protected static final int SELF_NAME

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ATTRIBUTE

protected static final int ATTRIBUTE

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ELEMENT

protected static final int ELEMENT

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BASE_URI

protected static final int BASE_URI

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LAST_FUN

protected static final int LAST_FUN

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Constructor Detail

Expr

protected Expr()

Method Detail

setListContext

public void setListContext(AbstractPattern listContext)

getListContext

public AbstractPattern getListContext()

isNumber

public boolean isNumber()

true if the expression prefers to return a number.

evalNumber

public double evalNumber(org.w3c.dom.Node node)
                  throws XPathException

Evaluates the expression as a double using the node as a context.

Parameters:

node - the node to evaluate and use as a context

Returns:

the numeric value.

Throws:

XPathException

evalNumber

public abstract double evalNumber(org.w3c.dom.Node node,
                                  ExprEnvironment env)
                           throws XPathException

Evaluates the expression as a number.

Parameters:

node - the current node.

env - variable environment.

Returns:

the numeric value.

Throws:

XPathException

isBoolean

public boolean isBoolean()

true if the expression prefers to return a boolean.

evalBoolean

public boolean evalBoolean(org.w3c.dom.Node node)
                    throws XPathException

Returns the boolean value of the node.

Parameters:

node - the node to evaluate and use as a context

Returns:

the boolean value

Throws:

XPathException

evalBoolean

public abstract boolean evalBoolean(org.w3c.dom.Node node,
                                    ExprEnvironment env)
                             throws XPathException

Returns the boolean value of the node.

Parameters:

node - the node to evaluate and use as a context

env - variable environment.

Returns:

the boolean value.

Throws:

XPathException

evalString

public java.lang.String evalString(org.w3c.dom.Node node)
                            throws XPathException

Returns the expression evaluated as a string.

Parameters:

node - the node to evaluate and use as a context

Returns:

the string value of the expression.

Throws:

XPathException

isString

public boolean isString()

true if the expression prefers to return a string.

evalString

public abstract java.lang.String evalString(org.w3c.dom.Node node,
                                            ExprEnvironment env)
                                     throws XPathException

Returns the string value of the node.

Parameters:

node - the node to evaluate and use as a context

env - variable environment.

Throws:

XPathException

evalString

public void evalString(CharBuffer cb,
                       org.w3c.dom.Node node)
                throws XPathException

Fills a char buffer with the evaluated string results.

Parameters:

cb - the buffer containing the results.

node - the node to evaluate and use as a context

Throws:

XPathException

evalString

public void evalString(CharBuffer cb,
                       org.w3c.dom.Node node,
                       ExprEnvironment env)
                throws XPathException

Fills a char buffer with the evaluated string results.

Parameters:

cb - the buffer containing the results.

node - the node to evaluate and use as a context

env - the variable environment

Throws:

XPathException

isNodeSet

public boolean isNodeSet()

true if the expression prefers to return a node set.

evalNodeSet

public NodeIterator evalNodeSet(org.w3c.dom.Node node)
                         throws XPathException

Returns an iterator of matching nodes

Parameters:

node - the node to evaluate and use as a context

Returns:

the value as a node iterator.

Throws:

XPathException

evalNodeSet

public NodeIterator evalNodeSet(org.w3c.dom.Node node,
                                ExprEnvironment env)
                         throws XPathException

Returns an iterator of matching nodes

Parameters:

node - the node to evaluate and use as a context

env - variable environment.

Returns:

the value as a node iterator.

Throws:

XPathException

evalObject

public java.lang.Object evalObject(org.w3c.dom.Node node)
                            throws XPathException

Returns the object value of the node.

Parameters:

node - the node to evaluate and use as a context

Throws:

XPathException

evalObject

public abstract java.lang.Object evalObject(org.w3c.dom.Node node,
                                            ExprEnvironment env)
                                     throws XPathException

Returns the object value of the node.

Parameters:

node - the node to evaluate and use as a context

env - variable environment.

Throws:

XPathException

evalVar

public Var evalVar(org.w3c.dom.Node node,
                   ExprEnvironment env)
            throws XPathException

Evaluates to a variable.

Parameters:

node - the node to evaluate and use as a context.

env - the variable environment.

Returns:

a variable containing the value.

Throws:

XPathException

addVar

public void addVar(Env newEnv,
                   java.lang.String name,
                   org.w3c.dom.Node node,
                   Env env)
            throws XPathException

Adds a variable with the expression's value.

Throws:

XPathException

setVar

public void setVar(java.lang.String name,
                   org.w3c.dom.Node node,
                   Env env)
            throws XPathException

Sets a variable with the expression's value.

Throws:

XPathException

addParam

public void addParam(Env newEnv,
                     java.lang.String name,
                     org.w3c.dom.Node node,
                     Env env)
              throws XPathException

Adds a param with the expression's value.

Throws:

XPathException

toBoolean

public static boolean toBoolean(java.lang.Object value)
                         throws XPathException

Convert a Java object to a boolean using the XPath rules.

Throws:

XPathException

toDouble

public static double toDouble(java.lang.Object value)
                       throws XPathException

Convert a Java object to a double using the XPath rules.

Throws:

XPathException

toString

public static java.lang.String toString(java.lang.Object value)
                                 throws XPathException

Convert a Java object to a string using the XPath rules.

Throws:

XPathException

toNode

public static org.w3c.dom.Node toNode(java.lang.Object value)
                               throws XPathException

Convert a Java object to a node using the XPath rules.

Throws:

XPathException

stringToNumber

protected static double stringToNumber(java.lang.String string)
                                throws XPathException

Convert a string to a double following XPath.

Parameters:

string - string to be treated as a double.

Returns:

the double value.

Throws:

XPathException

toNodeList

protected AbstractPattern toNodeList()

Convert from an expression to a pattern.