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package com.sun.jersey.server.impl.uri.rules.automata;
import com.sun.jersey.api.uri.UriPattern;
import com.sun.jersey.api.uri.UriTemplate;
import java.util.Iterator;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Represents a trie automata node.
* @author Frank D. Martinez. [email protected]
*/
public final class TrieNode {
/** TemplateParameters pattern regexp. */
public static final Pattern PARAMETER_PATTERN =
Pattern.compile("\\{([\\w-\\._~]+?)\\}");
/** Wildcard character */
private static final char WILDCARD_CHAR = '\0';
/** First child arc (this is a linked tree structure) */
private TrieArc firstArc;
/** Last child arc (this is a linked tree structure) */
private TrieArc lastArc;
/** arc counter */
private int arcs = 0;
/** Node's data */
private TrieNodeValue value = new TrieNodeValue();
/** Node's UriPattern used to match. */
private UriPattern pattern;
/** Tells if this node is a wildcard node */
private boolean wildcard = false;
/** wildcard setter.
* @param b New wildcard value.
*/
protected void setWildcard(boolean b) {
wildcard = b;
}
/** value setter.
* @param value New value.
* @param template Associated template.
*/
protected void setValue(T value, UriPattern pattern) {
this.value.set(value);
this.pattern = pattern;
}
/** Creates a new instance of TrieNode */
protected TrieNode() {
super();
}
/** Creates a new instance of TrieNode
* @param value Initial value.
*/
protected TrieNode(T value) {
this.value.set(value);
}
/**
* Search for a matching escape character in a wildcard sequence.
* @param c Test char.
*/
protected TrieArc matchExitArc(CharSequence seq, int i) {
TrieArc arc = firstArc;
while (arc != null) {
if (arc.match(seq, i) > 0) {
return arc;
}
arc = arc.next;
}
return null;
}
/**
* Tells if there is a value in this node.
*/
protected boolean hasValue() {
return !value.isEmpty();
}
/**
* Adds an arc at the end.
* @param arc New arc.
*/
private void addArc(TrieArc arc) {
if (firstArc == null) {
firstArc = arc;
}
else {
lastArc.next = arc;
}
lastArc = arc;
arcs++;
}
/**
* Adds a new node in the tree.
* @param path Tree position (URI)
* @param i Current position in path.
* @param value Value to be added at the end of path.
* @param pattern UriPattern associated with value.
*/
private boolean add(CharSequence path, int i, T value,
UriPattern pattern) {
// Case 1: NULL, The Last ----------------------------------------------
if (i >= path.length()) {
setValue(value, pattern);
return true;
}
// Case 2: Recursive add -----------------------------------------------
char input = path.charAt(i);
boolean added = false;
TrieArc arc = firstArc;
while (arc != null) {
if (arc.match(path, i) > 0) {
added = arc.target.add(path, i+1, value, pattern);
if (added) {
return added;
}
}
arc = arc.next;
}
// Case 3: Set as wildcard ---------------------------------------------
TrieNode node;
if (input == WILDCARD_CHAR) {
setWildcard(true);
return add(path, i+1, value, pattern);
}
// Case 4: Just Add ----------------------------------------------------
else {
node = new TrieNode();
addArc(new TrieArc(node, input));
return node.add(path, i+1, value, pattern);
}
}
/**
* Adds a new node to the tree.
* @param path Matching URI
* @param value Value to be added.
* @param template Associated UriPattern.
*/
protected void add(String path, T value, UriPattern pattern) {
// Replace All parameter macro by a WILDCARD character.
Matcher matcher = PARAMETER_PATTERN.matcher(path);
String uri = matcher.replaceAll(String.valueOf(WILDCARD_CHAR));
// If ends with '/', add the parent
if (uri.endsWith("/") && uri.length() > 1) {
add(uri.substring(0, uri.length()-1), 0, value, pattern);
}
// Add to root
add(uri, 0, value, pattern);
}
/**
* @see java.lang.Object#toString()
*/
@Override public String toString() {
StringBuilder out = new StringBuilder();
toStringRepresentation(out, 0, new char[] {'\0'});
return out.toString();
}
/**
* Builds a string representation of this subtree.
* @param out Output string.
* @param level indentation level.
* @param c Transition char.
*/
private void toStringRepresentation(StringBuilder out, int level, char[] c) {
for (int i=0; i");
out.append(getClass().getSimpleName() + (wildcard?"*":""));
out.append(" ");
out.append(value);
out.append('\n');
TrieArc arc = firstArc;
while (arc != null) {
arc.target.toStringRepresentation(out, level+2, arc.code);
arc = arc.next;
}
}
/** pattern getter. */
public UriPattern getPattern() {
return pattern;
}
/** value getter. */
public Iterator getValue() {
return value.getIterator();
}
/** wildcard getter. */
protected boolean isWildcard() {
return wildcard;
}
/** firstArch getter. */
protected TrieArc getFirstArc() {
return firstArc;
}
/** arcs getter. */
public int getArcs() {
return arcs;
}
/**
* Pack and optimize the automata.
*/
public void pack() {
TrieArc arc = firstArc;
while (arc != null) {
arc.pack();
arc = arc.next;
}
}
}