com.icl.saxon.functions
Class FormatNumber

java.lang.Object
  extended bycom.icl.saxon.expr.Expression
      extended bycom.icl.saxon.expr.Function
          extended bycom.icl.saxon.functions.FormatNumber

public class FormatNumber
extends Function


Field Summary
 
Fields inherited from class com.icl.saxon.expr.Function
argument
 
Fields inherited from class com.icl.saxon.expr.Expression
staticContext
 
Constructor Summary
FormatNumber()
           
 
Method Summary
 Value evaluate(Context c)
          Evaluate in a general context
 java.lang.String evaluateAsString(Context context)
          Evaluate in a context where a string is wanted
 java.lang.String formatNumber(double n, java.lang.String format, java.text.DecimalFormatSymbols dfs)
          Here is the method that does the work.
 int getDataType()
          Determine the data type of the exprEssion
 int getDependencies()
          Determine the dependencies
 java.lang.String getName()
          Get the name of the function.
 Expression reduce(int dep, Context c)
          Reduce the dependencies
 Expression simplify()
          Simplify and validate
 
Methods inherited from class com.icl.saxon.expr.Function
addArgument, checkArgumentCount, display, getNumberOfArguments
 
Methods inherited from class com.icl.saxon.expr.Expression
containsReferences, enumerate, evaluateAsBoolean, evaluateAsNodeSet, evaluateAsNumber, getStaticContext, indent, isContextDocumentNodeSet, make, outputStringValue, setStaticContext, usesCurrent
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

FormatNumber

public FormatNumber()
Method Detail

getName

public java.lang.String getName()
Description copied from class: Function
Get the name of the function. This method must be implemented in all subclasses.

Specified by:
getName in class Function
Returns:
the name of the function, as used in XSL expressions, but excluding its namespace prefix

getDataType

public int getDataType()
Determine the data type of the exprEssion

Specified by:
getDataType in class Expression
Returns:
Value.STRING

simplify

public Expression simplify()
                    throws XPathException
Simplify and validate

Overrides:
simplify in class Expression
Returns:
the simplified expression
Throws:
XPathException

evaluateAsString

public java.lang.String evaluateAsString(Context context)
                                  throws XPathException
Evaluate in a context where a string is wanted

Overrides:
evaluateAsString in class Expression
Parameters:
context - The context in which the expression is to be evaluated
Returns:
the value of the expression, evaluated in the current context
Throws:
XPathException

evaluate

public Value evaluate(Context c)
               throws XPathException
Evaluate in a general context

Specified by:
evaluate in class Expression
Parameters:
c - The context in which the expression is to be evaluated
Returns:
the value of the expression, evaluated in the current context
Throws:
XPathException

formatNumber

public java.lang.String formatNumber(double n,
                                     java.lang.String format,
                                     java.text.DecimalFormatSymbols dfs)
                              throws XPathException
Here is the method that does the work. It needs to be synchronized because it remembers information from one invocation to the next; it doesn't matter if these are in different threads but it can't be interrupted. The reason for remembering information is that getting a new DecimalFormatSymbols each time is incredibly expensive, especially with the Microsoft Java VM. Actually the synchronization is unnecessary if there is a bound Controller.

Throws:
XPathException

getDependencies

public int getDependencies()
Determine the dependencies

Specified by:
getDependencies in class Expression

reduce

public Expression reduce(int dep,
                         Context c)
                  throws XPathException
Reduce the dependencies

Specified by:
reduce in class Expression
Parameters:
dep - The dependencies to be removed, e.g. Context.VARIABLES
c - The context to be used for the partial evaluation
Returns:
a new expression (or Value) that does not have any of the specified dependencies
Throws:
XPathException