com.jcorporate.expresso.core.security.filters
Class FilterTree

java.lang.Object
  com.jcorporate.expresso.core.security.filters.FilterTree

public class FilterTree

extends Object

A filter tree is a data structure that allows for quick matching and replacement of strings. Use it for a fast 'search and replace' system. Construction and setup is a fairly expensive operation in comparison to the actual searching, so use it for static types of filters that are usually instantiated for a long time.

Author:

Michael Rimov

Field Summary

protected FilterTreeNode

root

Constructor Summary

FilterTree()

Method Summary

void	addFilterString(String specialString, String replacementString) Insert a filtering string into the parse tree.
FilterTreeNode	getRootNode()
String	replaceFilter(char[] input) Filters a string in a search and replace algorithm.

Methods inherited from class java.lang.Object

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

Field Detail

root

protected FilterTreeNode root

Constructor Detail

FilterTree

public FilterTree()

Method Detail

addFilterString

public void addFilterString(String specialString,
                            String replacementString)
                     throws Exception

Insert a filtering string into the parse tree.

Parameters:

specialString - the string to look for

replacementString - the string to replace it with.

Throws:

Exception - if insertNode() or setReplacementstring() fails

getRootNode

public FilterTreeNode getRootNode()

replaceFilter

public String replaceFilter(char[] input)

Filters a string in a search and replace algorithm. Uses a "greedy" approach so that it gets the biggest "fitting" string to cut.

Parameters:

input - character array to examine.

Returns:

The filtered string