prefuse.data.expression
Class ExpressionAnalyzer

java.lang.Object
  prefuse.data.expression.ExpressionAnalyzer

public class ExpressionAnalyzer
extends java.lang.Object

Library class that computes some simple analyses of an expression. Each analysis is computed using a visitor instance.

Author:

jeffrey heer

Constructor Summary

ExpressionAnalyzer()

Method Summary

static java.util.Set	getReferencedColumns(Expression expr) Get the set of data fields the expression is dependent upon.
static boolean	hasDependency(Expression expr) Determine if an expression has a dependency on a data field.

Methods inherited from class java.lang.Object

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

Constructor Detail

ExpressionAnalyzer

public ExpressionAnalyzer()

Method Detail

hasDependency

public static boolean hasDependency(Expression expr)

Determine if an expression has a dependency on a data field.

Parameters:

expr - the expression to analyze

Returns:

true if the expression has at least one tuple data field dependency.

getReferencedColumns

public static java.util.Set getReferencedColumns(Expression expr)

Get the set of data fields the expression is dependent upon.

Parameters:

expr - the expression to analyze

Returns:

a set of all data field names the expression references