File	Doc	Category	Size	Date	Package
FuncExtFunction.java	API Doc	Java SE 6 API	9379	Tue Jun 10 00:23:14 BST 2008	com.sun.org.apache.xpath.internal.functions

FuncExtFunction

• java.lang.Object
  • com.sun.org.apache.xpath.internal.Expression
    • com.sun.org.apache.xpath.internal.functions.Function

Fields Summary
static final long	serialVersionUID
String	m_namespace The namespace for the extension function, which should not normally be null or empty.
String	m_extensionName The local name of the extension.
Object	m_methodKey Unique method key, which is passed to ExtensionsTable#extFunction in order to allow caching of the method.
Vector	m_argVec Array of static expressions which represent the parameters to the function.

Constructors Summary

public FuncExtFunction(String namespace, String extensionName, Object methodKey) Create a new FuncExtFunction based on the qualified name of the extension, and a unique method key. param namespace The namespace for the extension function, which should not normally be null or empty. param extensionName The local name of the extension. param methodKey Unique method key, which is passed to ExtensionsTable#extFunction in order to allow caching of the method. //try{throw new Exception("FuncExtFunction() " + namespace + " " + extensionName);} catch (Exception e){e.printStackTrace();} m_namespace = namespace; m_extensionName = extensionName; m_methodKey = methodKey;

Methods Summary
public void	callArgVisitors(com.sun.org.apache.xpath.internal.XPathVisitor visitor) Call the visitors for the function arguments. for (int i = 0; i < m_argVec.size(); i++) { Expression exp = (Expression)m_argVec.elementAt(i); exp.callVisitors(new ArgExtOwner(exp), visitor); }
public void	checkNumberArgs(int argNum) Check that the number of arguments passed to this function is correct. param argNum The number of arguments that is being passed to the function. throws WrongNumberArgsException
public com.sun.org.apache.xpath.internal.objects.XObject	execute(com.sun.org.apache.xpath.internal.XPathContext xctxt) Execute the function. The function must return a valid object. param xctxt The current execution context. return A valid XObject. throws javax.xml.transform.TransformerException if (xctxt.isSecureProcessing()) throw new javax.xml.transform.TransformerException( XPATHMessages.createXPATHMessage( XPATHErrorResources.ER_EXTENSION_FUNCTION_CANNOT_BE_INVOKED, new Object[] {toString()})); XObject result; Vector argVec = new Vector(); int nArgs = m_argVec.size(); for (int i = 0; i < nArgs; i++) { Expression arg = (Expression) m_argVec.elementAt(i); XObject xobj = arg.execute(xctxt); /* * Should cache the arguments for func:function */ xobj.allowDetachToRelease(false); argVec.addElement(xobj); } //dml ExtensionsProvider extProvider = (ExtensionsProvider)xctxt.getOwnerObject(); Object val = extProvider.extFunction(this, argVec); if (null != val) { result = XObject.create(val, xctxt); } else { result = new XNull(); } return result;
public void	exprSetParent(com.sun.org.apache.xpath.internal.ExpressionNode n) Set the parent node. For an extension function, we also need to set the parent node for all argument expressions. param n The parent node super.exprSetParent(n); int nArgs = m_argVec.size(); for (int i = 0; i < nArgs; i++) { Expression arg = (Expression) m_argVec.elementAt(i); arg.exprSetParent(n); }
public void	fixupVariables(java.util.Vector vars, int globalsSize) This function is used to fixup variables from QNames to stack frame indexes at stylesheet build time. param vars List of QNames that correspond to variables. This list should be searched backwards for the first qualified name that corresponds to the variable reference qname. The position of the QName in the vector from the start of the vector will be its position in the stack frame (but variables above the globalsTop value will need to be offset to the current stack frame). NEEDSDOC @param globalsSize if (null != m_argVec) { int nArgs = m_argVec.size(); for (int i = 0; i < nArgs; i++) { Expression arg = (Expression) m_argVec.elementAt(i); arg.fixupVariables(vars, globalsSize); } }
public com.sun.org.apache.xpath.internal.Expression	getArg(int n) Return the nth argument passed to the extension function. param n The argument number index. return The Expression object at the given index. if (n >= 0 && n < m_argVec.size()) return (Expression) m_argVec.elementAt(n); else return null;
public int	getArgCount() Return the number of arguments that were passed into this extension function. return The number of arguments. return m_argVec.size();
public java.lang.String	getFunctionName() Return the name of the extension function. return The name of the extension function. return m_extensionName;
public java.lang.Object	getMethodKey() Return the method key of the extension function. return The method key of the extension function. return m_methodKey;
public java.lang.String	getNamespace() Return the namespace of the extension function. return The namespace of the extension function. return m_namespace;
protected void	reportWrongNumberArgs() Constructs and throws a WrongNumberArgException with the appropriate message for this function object. This class supports an arbitrary number of arguments, so this method must never be called. throws WrongNumberArgsException String fMsg = XSLMessages.createXPATHMessage( XPATHErrorResources.ER_INCORRECT_PROGRAMMER_ASSERTION, new Object[]{ "Programmer's assertion: the method FunctionMultiArgs.reportWrongNumberArgs() should never be called." }); throw new RuntimeException(fMsg);
public void	setArg(com.sun.org.apache.xpath.internal.Expression arg, int argNum) Set an argument expression for a function. This method is called by the XPath compiler. param arg non-null expression that represents the argument. param argNum The argument number index. throws WrongNumberArgsException If the argNum parameter is beyond what is specified for this function. m_argVec.addElement(arg); arg.exprSetParent(this);
public java.lang.String	toString() Return the name of the extesion function in string format if (m_namespace != null && m_namespace.length() > 0) return "{" + m_namespace + "}" + m_extensionName; else return m_extensionName;