condor.classad
Class FuncCall

Object
  condor.classad.Expr
      condor.classad.FuncCall

public class FuncCall

extends Expr

A function call. An internal (non-leaf) node of an expression tree representing a function name and list of arguments.

Version:

2.2

Author:

Marvin Solomon

See Also:

Expr

Field Summary

List	args The raw parameters to the function.
AttrName	func The name of the function as supplied in the original source.

Fields inherited from class condor.classad.Expr

ABSOLUTE_TIME, AND, ATTRIBUTE, BIT_COMPLEMENT, BITAND, BITOR, BITXOR, BOOLEAN, CALL, COND, dblevel, DIFFERENT, DIV, EQUAL, ERROR, GREATER, GREATER_EQ, INTEGER, LEFT_SHIFT, LESS, LESS_EQ, LIST, MAXPREC, MINUS, MOD, NOT, NOT_EQUAL, OP, opName, opNameXML, OR, PLUS, RECORD, RELATIVE_TIME, RIGHT_SHIFT, SAME, SELECTION, STRING, SUBSCRIPT, TIMES, type, UMINUS, UNDEFINED, UPLUS, URIGHT_SHIFT

Method Summary

protected Expr	eval1(Env env) Evaluate this Expr.
static Expr	getInstance(AttrName func, List params) Create a function node from a name and a list of paramters.
(package private) static boolean	loadJavaLibrary(String className) Loads a library of externally defined Java functions.
int	prec() The precedence of the operator in this expression node.
boolean	sameAs(Expr other) Compare this Expr to another expression to check for "deep structural equality".
StringBuffer	toString(StringBuffer sb) Convert this Expr to a string, appending the result to the end of "sb".

Methods inherited from class condor.classad.Expr

db, db, eval, eval, intValue, is, isConstant, isTrue, realValue, selectExpr, stringValue, subExpr, toString, typeName

Methods inherited from class Object

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

Field Detail

func

public final AttrName func

The name of the function as supplied in the original source.

args

public final List args

The raw parameters to the function.

Method Detail

getInstance

public static Expr getInstance(AttrName func,
                               List params)

Create a function node from a name and a list of paramters. This method has a special hack for "constant folding" of certain calls. If the function name is absTime or relTime (ignoring case) and there is exactly one argument, of type String, then return the appropriate constant. In all other cases, just return a new FuncCall object.

Parameters:

func - the name of the function (original case).

params - the parameters supplied.

Returns:

an Exp of type CALL, ABS_TIME, REL_TIME, REAL, or ERROR.

toString

public StringBuffer toString(StringBuffer sb)

Convert this Expr to a string, appending the result to the end of "sb". The representation is the "canonical native format": name '(' [ arg [ ',' arg ]* ')' with no extra spaces.

Specified by:

toString in class Expr

Parameters:

sb - a place to put the result.

Returns:

sb.

See Also:

ClassAdWriter

sameAs

public boolean sameAs(Expr other)

Compare this Expr to another expression to check for "deep structural equality".

Specified by:

sameAs in class Expr

Parameters:

other - the other expression

Returns:

true of this and the other expression are isomorphic.

eval1

protected Expr eval1(Env env)

Evaluate this Expr. This is the internal method used to implement Expr.eval(). By default, all functions are "strict" in all their arguments. That is, all arguments are evaluated before the function is called, and if any argument evaluates to an undefined or error Constant, the value of the call is undefined or error, with error taking precendence over undefined. In this case, the message is taken from the first argument that evaluates to an error or undefined. Functions can be flagged as "non-strict", in which case all evaluation of arguments is inhibited, and the function implementation is responsible for evaluating arguments as necessary.

We assume at this time that there are no built-in strict functions that take a RecordExpr or ListExpr as an argument.

Specified by:

eval1 in class Expr

Parameters:

env - an environment used to evaluate the operands. It is cleared to the null environment before return.

Returns:

a Constant representing the value.

prec

public int prec()

The precedence of the operator in this expression node. Used to print expressions without superfluous parentheses. Function calls have maximal precedence (higher than any operator).

Specified by:

prec in class Expr

Returns:

the precendence of this node.

See Also:

ClassAdWriter.MINIMAL_PARENTHESES

loadJavaLibrary

static boolean loadJavaLibrary(String className)

Loads a library of externally defined Java functions. Meant to be called from ClassAd.loadJavaLibrary.

Parameters:

className - the fully qualified name of the class (e.g. condor.classad.Builtin)

Returns:

false if the load fails.

See Also:

ClassAd.loadJavaLibrary(java.lang.String)