vec_math
Class ExpressionCalculator

java.lang.Object
  util.PropertyContainer
      util.PropertyResources
          util.PropertyBundles
              vec_math.ExpressionCalculator

All Implemented Interfaces:

Cloneable, Initializable, LocalizedSupplying, PropertySupplying, ResourceSupplying

Direct Known Subclasses:

ExposureTime

public class ExpressionCalculator
extends PropertyBundles
implements Initializable

Combines an ExpressionNode and an ExpressionParser to actually fill paramtere values into an expression and evaluate this.

Nested Class Summary

Nested classes/interfaces inherited from class util.PropertyResources

PropertyResources.URLResource

Field Summary

private ExpressionNode	expression The parsable double expression.
static String	KEY_INITEXPRESSION The evaluator uses this expression for parsing.

Fields inherited from class util.PropertyBundles

KEY_LOCALECOUNTRY, KEY_LOCALELANGUAGE, KEY_RESOURCEBUNDLES

Fields inherited from class util.PropertyResources

KEY_NOINITONCREATE, localurl, locate, POSTFIX_DIR, POSTFIX_EXT, POSTFIX_FILE, POSTFIX_LIST, POSTFIX_URL, urlset

Fields inherited from class util.PropertyContainer

KEY_LISTSEPARATOR, KEY_MAPKEYVALUECHAR, KEY_MAPSEPARATOR

Fields inherited from interface util.ResourceSupplying

KEY_URLRESOURCES, KEY_URLUSECONFIG, KEY_URLUSECURRENT, KEY_URLUSEHOME

Fields inherited from interface util.PropertySupplying

CONFIG, KEY_CLASS

Constructor Summary

ExpressionCalculator(Map<String,String> init)
Constructs a new expression evaluator.

Method Summary

Number	evaluate(Map<String,Object> set) Returns the actual value of the expression.
ExpressionNode	getExpression() Returns the initial expression.
void	init() If the calculator has a property named KEY_INITEXPRESSION, we use this expression to initialize the calculator.
void	initCalculator(String node) Initializes the expression.

Methods inherited from class util.PropertyBundles

clone, getLocalized, getLocalized, getLocalizedString, getLocalizedString, loadResource

Methods inherited from class util.PropertyResources

createFrom, createFrom, createFrom, getApplet, getAsResources, getLocalClassLoader, getPropertiesToKey, getPropertiesToKey, getResource, getResourceAsStream, getResourceFromKey, getResources, keyCreate, keyCreate, reload, setApplet

Methods inherited from class util.PropertyContainer

augment, augment, augment, defaultBoolean, defaultChar, defaultDouble, defaultFloat, defaultInt, defaultLong, defaultObject, defaultObject, defaultProperties, defaultProperty, getAsBoolean, getAsChar, getAsDouble, getAsEnums, getAsFloat, getAsInt, getAsList, getAsLong, getAsMap, getAsMap, getAsObject, getAsObject, getProperties, getProperty, has, isNew, parseObject, reload, removeProperty, rescanned, setObject, setProperties, setProperty, stringProperties, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface util.ResourceSupplying

getResource, getResourceAsStream, getResources

Methods inherited from interface util.PropertySupplying

defaultBoolean, defaultChar, defaultDouble, defaultFloat, defaultInt, defaultLong, defaultObject, defaultObject, defaultProperties, defaultProperty, getAsBoolean, getAsChar, getAsDouble, getAsFloat, getAsInt, getAsList, getAsLong, getAsMap, getAsObject, getAsObject, getProperties, getProperty, has, parseObject, removeProperty, setObject, setProperty, stringProperties

Field Detail

KEY_INITEXPRESSION

public static final String KEY_INITEXPRESSION

The evaluator uses this expression for parsing.

See Also:

Constant Field Values

expression

private ExpressionNode expression

The parsable double expression.

Constructor Detail

ExpressionCalculator

public ExpressionCalculator(Map<String,String> init)

Constructs a new expression evaluator. The properties can be used for additional variables that should be available to the evaluator.

Method Detail

init

public void init()

If the calculator has a property named KEY_INITEXPRESSION, we use this expression to initialize the calculator.

Specified by:

init in interface Initializable

Overrides:

init in class PropertyResources

initCalculator

public void initCalculator(String node)

Initializes the expression. Variable substitution is done in the evaluate(java.util.Map) method. Proper parsing is only possible if the argument follows the generic ExpressionNode specification.

Parameters:

node - A String expression.

evaluate

public Number evaluate(Map<String,Object> set)

Returns the actual value of the expression. Variables that are TargetDependingParameters are evaluted using the target definition. Variable names must either be substitutable from the parameter cluster handed over or specified as constants in the DTDConstants.CONSTANT section of the merit. The sequence of parameter substitution first looks up the merit's constant. Only if the variable is not a defined constant, it is evaluated using the parameter set.

Returns:

Either a Double or a Boolean

getExpression

public ExpressionNode getExpression()

Returns the initial expression.