de.fzi.power.interpreter.calculator.expressionoasis.custom

Class CustomFunctionProvider

java.lang.Object

de.fzi.power.interpreter.calculator.expressionoasis.custom.CustomFunctionProvider

All Implemented Interfaces:

FunctionProvider

public final class CustomFunctionProvider
extends Object
implements FunctionProvider

Field Summary

Fields

Modifier and Type	Field and Description
static String	POW The provided composite 'POW' function.
static String	SQRT The provided composite 'SQRT' function.

Constructor Summary

Constructors

Constructor and Description
CustomFunctionProvider()

Method Summary

Modifier and Type	Method and Description
Type	getFunctionType(String functionName, Type[] parameterTypes) Gets the return type of the function.
ValueObject	getFunctionValue(String functionName, ValueObject[] parameters) Gets the return value of function.
void	initialize(ExpressionContext expressionContext) It initialize the Function provider with expression context and also gives a chance to pre-initialize any internal states for operations
boolean	supportsFunction(String functionName, Type[] parameterTypes) Checks whether the this function provider supports any function or not.

Methods inherited from class java.lang.Object

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

Field Detail

POW

public static final String POW

The provided composite 'POW' function.

See Also:

Constant Field Values

SQRT

public static final String SQRT

The provided composite 'SQRT' function.

See Also:

Constant Field Values

Constructor Detail

CustomFunctionProvider

public CustomFunctionProvider()

Method Detail

initialize

public void initialize(ExpressionContext expressionContext)

Description copied from interface: FunctionProvider

It initialize the Function provider with expression context and also gives a chance to pre-initialize any internal states for operations

Specified by:

initialize in interface FunctionProvider

Parameters:

expressionContext - Context of current expression evaluation process

Throws:

AssertionError - In case the passed ExpressionContext is not a CustomExpressionContext instance.

getFunctionType

public Type getFunctionType(String functionName,
                            Type[] parameterTypes)
                     throws ExpressionEngineException

Description copied from interface: FunctionProvider

Gets the return type of the function.

Specified by:

getFunctionType in interface FunctionProvider

Parameters:

functionName - the name of the function.

parameterTypes - the types of the parameters

Returns:

Type.DOUBLE in case supportsFunction(String, Type[]) called with the given arguments returns true, otherwise null.

Throws:

ExpressionEngineException - if anything goes wrong

getFunctionValue

public ValueObject getFunctionValue(String functionName,
                                    ValueObject[] parameters)
                             throws ExpressionEngineException

Gets the return value of function.

Specified by:

getFunctionValue in interface FunctionProvider

Parameters:

functionName - the name of the function

parameters - the parameters values of the function

Returns:

• null is returned in case the function denoted by the given name is not provided by this instance.
• A ValueObject of Type.DOUBLE is returned if none of the parameters is a MeasuredFactor.
• A MeasuredValuesCompositeValueObject is returned in any other case.

Throws:

ExpressionEngineException - if anything goes wrong

supportsFunction

public boolean supportsFunction(String functionName,
                                Type[] parameterTypes)
                         throws ExpressionEngineException

Description copied from interface: FunctionProvider

Checks whether the this function provider supports any function or not.

Specified by:

supportsFunction in interface FunctionProvider

Parameters:

functionName - the name of the function

parameterTypes - the type of parameters for the function

Returns:

true if function provider supports the function false otherwise

Throws:

ExpressionEngineException - if anything goes wrong