org.eclipse.tptp.platform.provisional.fastxpath
Interface IFastXPathEngine

All Known Implementing Classes:

FastXPathEngine, FastXPathEngine

public interface IFastXPathEngine

Since:

4.2

Method Summary

CompiledExpressionEvaluator	compile(java.lang.String expression, java.lang.Object object, boolean verifyExpression, FastXPathContext fastXPathContext, ICompilerContext compilationContext, CompilerPostProcessor compilerPostProcessor, ICompilerHelper cHelper)
CompiledExpressionEvaluator	compile(java.lang.String expression, java.lang.Object object, ICompilerHelper cHelper) Generates a Java expression equivalent to the XPath expression.
ICompilerHelper	createCompilerHelper(java.lang.Class targetClass)
java.lang.Object	eval(java.lang.String expression, java.lang.Object object) Perform XPath query on an EObject.
java.lang.Object	evalCompiled(CompiledExpressionEvaluator evaluator, java.lang.Object object) Executes the compiled expression on EObject.
java.util.Map	getClassesAsByteArrays()
FastXPathClassGenerator	getClassGenerator()
java.lang.Object	getExpression(java.lang.String expression)
char[]	getExpressionJavaSource(java.lang.String expression, java.lang.Object object, boolean verifyExpression, FastXPathContext fastXPathContext, ICompilerContext compilationContext, CompilerPostProcessor compilerPostProcessor, ICompilerHelper cHelper) Generates the source code of a Java expression equivalent to the XPath expression.
java.lang.Class	getExtensionFunctionClass(java.lang.String key) Returns the Class of the extension function
FastXPathContextFactory	getFastXPathContextFactory()
java.lang.String	getVariable(java.lang.String key)
void	registerFunctionClass(java.lang.Class functionClass, java.lang.String key) * Registers a Class that contains extension functions.
void	registerVariable(java.lang.String key, java.lang.String newValue) registers a new variable
void	resetDeclaredVariables() Resets the declared variables map
void	resetExpressions() Resets the known expressions cache
java.lang.Object[]	selectNodes(java.lang.String expression, java.lang.Object object) Perform XPath query on an EObject.
void	setFastXPathContextFactory(FastXPathContextFactory fastXPathContextFactory)
void	unRegisterFunctionClass(java.lang.String key) unregisters a registered extension function class
void	unRegisterVariable(java.lang.String key) unregisters a variable

Method Detail

selectNodes

public java.lang.Object[] selectNodes(java.lang.String expression,
                                      java.lang.Object object)
                               throws javax.xml.transform.TransformerException,
                                      ExpressionEvaluationException

Perform XPath query on an EObject. The result may be several node

Parameters:

expression - the XPath expression to evaluate

object - the EObject to be evaluated

Returns:

Result of the query. If no node match, an empty array is returned.

Throws:

javax.xml.transform.TransformerException

ExpressionEvaluationException

eval

public java.lang.Object eval(java.lang.String expression,
                             java.lang.Object object)
                      throws javax.xml.transform.TransformerException,
                             ExpressionEvaluationException

Perform XPath query on an EObject. If several node match the query, only the first is returned

Parameters:

expression - the XPath expression to evaluate

object - the EObject to be evaluated

Returns:

Result of the query. null if there is no match.

Throws:

javax.xml.transform.TransformerException

ExpressionEvaluationException

evalCompiled

public java.lang.Object evalCompiled(CompiledExpressionEvaluator evaluator,
                                     java.lang.Object object)
                              throws ExpressionEvaluationException

Executes the compiled expression on EObject. CompiledExpressionEvaluator are generated by calling FastXPathEngine#compile(String, Object, CompilerHelper). It is up to the user to cache the different CompiledExpressionEvaluators

Parameters:

evaluator -

object - the EObject to be evaluated

Returns:

Result of the query. null if there is no match.

Throws:

ExpressionEvaluationException

compile

public CompiledExpressionEvaluator compile(java.lang.String expression,
                                           java.lang.Object object,
                                           ICompilerHelper cHelper)
                                    throws javax.xml.transform.TransformerException,
                                           CodeGenerationError,
                                           CompilerNotAvailableException

Generates a Java expression equivalent to the XPath expression. This compiled expression can later be evaluated using evalCompiled(CompiledExpressionEvaluator, Object)

Parameters:

expression - the XPath expression to generate code from

object - The compiiler needs an instance of the type of Object that the CompiledExpressionEvaluator will be specialized for.

cHelper - A helper Class to configure the compilation process. Can be null.

Returns:

A (@link CompiledExpressionEvaluator} specialized for the expressionobject and the object type.

Throws:

javax.xml.transform.TransformerException

CodeGenerationError

CompilerNotAvailableException

compile

public CompiledExpressionEvaluator compile(java.lang.String expression,
                                           java.lang.Object object,
                                           boolean verifyExpression,
                                           FastXPathContext fastXPathContext,
                                           ICompilerContext compilationContext,
                                           CompilerPostProcessor compilerPostProcessor,
                                           ICompilerHelper cHelper)
                                    throws javax.xml.transform.TransformerException,
                                           CodeGenerationError,
                                           CompilerNotAvailableException

Throws:

javax.xml.transform.TransformerException

CodeGenerationError

CompilerNotAvailableException

getExpressionJavaSource

public char[] getExpressionJavaSource(java.lang.String expression,
                                      java.lang.Object object,
                                      boolean verifyExpression,
                                      FastXPathContext fastXPathContext,
                                      ICompilerContext compilationContext,
                                      CompilerPostProcessor compilerPostProcessor,
                                      ICompilerHelper cHelper)
                               throws javax.xml.transform.TransformerException,
                                      CodeGenerationError,
                                      CompilerNotAvailableException

Generates the source code of a Java expression equivalent to the XPath expression.

Parameters:

expression - the XPath expression to generate code from

object - The compiler needs an instance of the type of Object that the CompiledExpressionEvaluator will be specialized for.

verifyExpression - If true the expression is evaluated to check if it is a valid expression.

fastXPathContext - If not null will be used otherwise a new one will be created.

compilationContext - If not null will be used otherwise a new one will be created.

compilerPostProcessor - If not null will be initialized and used otherwise a new one will be created.

Returns:

A String that contains the Java body of the expresion.

Throws:

javax.xml.transform.TransformerException

CodeGenerationError

CompilerNotAvailableException

resetExpressions

public void resetExpressions()

Resets the known expressions cache

resetDeclaredVariables

public void resetDeclaredVariables()

Resets the declared variables map

getVariable

public java.lang.String getVariable(java.lang.String key)

Parameters:

key - name of the variable to return

Returns:

Returns the variable named key

registerVariable

public void registerVariable(java.lang.String key,
                             java.lang.String newValue)

registers a new variable

Parameters:

key - name of the variable

newValue - value of the variable

unRegisterVariable

public void unRegisterVariable(java.lang.String key)

unregisters a variable

Parameters:

key - name of the variable

getExtensionFunctionClass

public java.lang.Class getExtensionFunctionClass(java.lang.String key)

Returns the Class of the extension function

Parameters:

key - the key by which the Class is registered

Returns:

the Class of the extension function

registerFunctionClass

public void registerFunctionClass(java.lang.Class functionClass,
                                  java.lang.String key)

* Registers a Class that contains extension functions.

Parameters:

functionClass - name of the class

key - the key it is registered by. The same key is used in the XPath expressions referencing to this class

unRegisterFunctionClass

public void unRegisterFunctionClass(java.lang.String key)

unregisters a registered extension function class

Parameters:

key - the key the class was registered as.

getExpression

public java.lang.Object getExpression(java.lang.String expression)
                               throws javax.xml.transform.TransformerException

Parameters:

expression -

Returns:

EXPath

Throws:

javax.xml.transform.TransformerException

getFastXPathContextFactory

public FastXPathContextFactory getFastXPathContextFactory()

Returns:

the fastXPathContextFactory

setFastXPathContextFactory

public void setFastXPathContextFactory(FastXPathContextFactory fastXPathContextFactory)

createCompilerHelper

public ICompilerHelper createCompilerHelper(java.lang.Class targetClass)

getClassesAsByteArrays

public java.util.Map getClassesAsByteArrays()

getClassGenerator

public FastXPathClassGenerator getClassGenerator()
                                          throws CompilerNotAvailableException

Throws:

CompilerNotAvailableException