org.jsimpledb.parse.func

Class ApplyExprFunction

java.lang.Object

org.jsimpledb.parse.func.AbstractFunction

org.jsimpledb.parse.func.ApplyExprFunction

All Implemented Interfaces:

Function

Direct Known Subclasses:

FilterFunction, ForEachFunction, TransformFunction

public abstract class ApplyExprFunction
extends AbstractFunction

Field Summary

Fields inherited from class org.jsimpledb.parse.func.AbstractFunction

log, name, spaceParser

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ApplyExprFunction(String name)

Method Summary

Modifier and Type	Method and Description
protected abstract Value	apply(ParseSession session, org.jsimpledb.parse.func.ApplyExprFunction.ParamInfo params) Apply this function.
Value	apply(ParseSession session, Object params) Evaluate this function.
protected Value	evaluate(ParseSession session, String variable, Value value, Node expr) Set the variable to the given value and then evaluate the expression.
org.jsimpledb.parse.func.ApplyExprFunction.ParamInfo	parseParams(ParseSession session, ParseContext ctx, boolean complete) Parse function parameters.

Methods inherited from class org.jsimpledb.parse.func.AbstractFunction

getHelpDetail, getName, getSessionModes, parseExpressionParams, parseNextParameter

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.jsimpledb.parse.func.Function

getHelpSummary, getUsage

Constructor Detail

ApplyExprFunction

protected ApplyExprFunction(String name)

Method Detail

parseParams

public org.jsimpledb.parse.func.ApplyExprFunction.ParamInfo parseParams(ParseSession session,
                                                                        ParseContext ctx,
                                                                        boolean complete)

Description copied from interface: Function

Parse function parameters.

The ctx will be pointing at the first parameter (if any) or closing parenthesis. This method should parse (but not evaluate) function parameters up through the closing parenthesis. The return value is an opaque value representing the parsed parameters and subsequently passed to apply().

Parameters:

session - parse session

ctx - parse context

complete - false if parse is "for real", true if only for tab completion calculation

Returns:

parsed parameters object to be passed to apply()

apply

public final Value apply(ParseSession session,
                         Object params)

Description copied from interface: Function

Evaluate this function. There will be a transaction open.

Parameters:

session - parse session

params - parsed parameters returned by parseParams()

Returns:

value returned by this function

apply

protected abstract Value apply(ParseSession session,
                               org.jsimpledb.parse.func.ApplyExprFunction.ParamInfo params)

Apply this function.

Parameters:

session - parse session

params - function parameters

Returns:

the value of this function

evaluate

protected Value evaluate(ParseSession session,
                         String variable,
                         Value value,
                         Node expr)

Set the variable to the given value and then evaluate the expression. Any previous value of the variable is saved prior and restored after.

Parameters:

session - parse session

variable - the name of the variable to use

value - the value to set to the variable

expr - the expression to evaluate

Returns:

the value of the expression