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Tiles Core Library, including basic implementation of the APIs. Upgraded to the Jakarta EE platform.
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/*
* $Id$
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.tiles.util;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
/**
* This class is an utility class that perform wilcard-patterns matching and
* isolation taken from Apache Struts that is taken, in turn, from Apache
* Struts.
*
* @version $Rev$ $Date$
* @since 2.1.0
*/
public class WildcardHelper {
/**
* The int representing '*' in the pattern int [].
*
* @since 2.1.0
*/
protected static final int MATCH_FILE = -1;
/**
* The int representing '**' in the pattern int [].
*
* @since 2.1.0
*/
protected static final int MATCH_PATH = -2;
/**
* The int representing begin in the pattern int [].
*
* @since 2.1.0
*/
protected static final int MATCH_BEGIN = -4;
/**
* The int representing end in pattern int [].
*
* @since 2.1.0
*/
protected static final int MATCH_THEEND = -5;
/**
* The int value that terminates the pattern int [].
*
* @since 2.1.0
*/
protected static final int MATCH_END = -3;
/**
* The length of the placeholder.
*
* @since 2.1.0
*/
private static final int PLACEHOLDER_LENGTH = 3;
/**
*
* Translate the given String into a int []
* representing the pattern matchable by this class.
* This function translates a String into an int array
* converting the special '*' and '\' characters.
* Here is how the conversion algorithm works:
*
*
*
*
* - The '*' character is converted to MATCH_FILE, meaning that zero or
* more characters (excluding the path separator '/') are to be matched.
*
* - The '**' sequence is converted to MATCH_PATH, meaning that zero or
* more characters (including the path separator '/') are to be matched.
*
* - The '\' character is used as an escape sequence ('\*' is translated
* in '*', not in MATCH_FILE). If an exact '\' character is to be matched
* the source string must contain a '\\'. sequence.
*
*
*
*
* When more than two '*' characters, not separated by another character,
* are found their value is considered as '**' (MATCH_PATH).
* The array is always terminated by a special value (MATCH_END).
* All MATCH* values are less than zero, while normal characters are equal
* or greater.
*
*
* @param data The string to translate.
* @return The encoded string as an int array, terminated by the MATCH_END
* value (don't consider the array length).
* @throws NullPointerException If data is null.
* @since 2.1.0
*/
public int[] compilePattern(String data) {
// Prepare the arrays
int[] expr = new int[data.length() + 2];
char[] buff = data.toCharArray();
// Prepare variables for the translation loop
int y = 0;
boolean slash = false;
// Must start from beginning
expr[y++] = MATCH_BEGIN;
if (buff.length > 0) {
if (buff[0] == '\\') {
slash = true;
} else if (buff[0] == '*') {
expr[y++] = MATCH_FILE;
} else {
expr[y++] = buff[0];
}
// Main translation loop
for (int x = 1; x < buff.length; x++) {
// If the previous char was '\' simply copy this char.
if (slash) {
expr[y++] = buff[x];
slash = false;
// If the previous char was not '\' we have to do a bunch of
// checks
} else {
// If this char is '\' declare that and continue
if (buff[x] == '\\') {
slash = true;
// If this char is '*' check the previous one
} else if (buff[x] == '*') {
// If the previous character als was '*' match a path
if (expr[y - 1] <= MATCH_FILE) {
expr[y - 1] = MATCH_PATH;
} else {
expr[y++] = MATCH_FILE;
}
} else {
expr[y++] = buff[x];
}
}
}
}
// Must match end at the end
expr[y] = MATCH_THEEND;
return expr;
}
/**
* Match a pattern agains a string and isolates wildcard replacement into a
* Stack.
*
* @param data The string to match
* @param expr The compiled wildcard expression
* @return The list of matched variables, or null if it does not match.
* @throws NullPointerException If any parameters are null
* @since 2.2.0
*/
public List match(String data, int[] expr) {
List varsValues = null;
if (data == null) {
throw new NullPointerException("No data provided");
}
if (expr == null) {
throw new NullPointerException("No pattern expression provided");
}
char[] buff = data.toCharArray();
// Allocate the result buffer
char[] rslt = new char[expr.length + buff.length];
// The previous and current position of the expression character
// (MATCH_*)
int charpos = 0;
// The position in the expression, input, translation and result arrays
int exprpos = 0;
int buffpos = 0;
int rsltpos = 0;
int offset = -1;
// First check for MATCH_BEGIN
boolean matchBegin = false;
if (expr[charpos] == MATCH_BEGIN) {
matchBegin = true;
exprpos = ++charpos;
}
// Search the fist expression character (except MATCH_BEGIN - already
// skipped)
while (expr[charpos] >= 0) {
charpos++;
}
// The expression charater (MATCH_*)
int exprchr = expr[charpos];
while (true) {
// Check if the data in the expression array before the current
// expression character matches the data in the input buffer
if (matchBegin) {
if (!matchArray(expr, exprpos, charpos, buff, buffpos)) {
return null;
}
matchBegin = false;
} else {
offset = indexOfArray(expr, exprpos, charpos, buff, buffpos);
if (offset < 0) {
return null;
}
}
// Check for MATCH_BEGIN
if (matchBegin) {
if (offset != 0) {
return null;
}
matchBegin = false;
}
// Advance buffpos
buffpos += (charpos - exprpos);
// Check for END's
if (exprchr == MATCH_END) {
if (rsltpos > 0) {
varsValues = addAndCreateList(varsValues, new String(rslt,
0, rsltpos));
}
// Don't care about rest of input buffer
varsValues = addElementOnTop(varsValues, data);
return varsValues;
} else if (exprchr == MATCH_THEEND) {
if (rsltpos > 0) {
varsValues = addAndCreateList(varsValues, new String(rslt,
0, rsltpos));
}
// Check that we reach buffer's end
if (buffpos == buff.length) {
addElementOnTop(varsValues, data);
return varsValues;
}
return null;
}
// Search the next expression character
exprpos = ++charpos;
while (expr[charpos] >= 0) {
charpos++;
}
int prevchr = exprchr;
exprchr = expr[charpos];
// We have here prevchr == * or **.
offset = (prevchr == MATCH_FILE) ? indexOfArray(expr, exprpos,
charpos, buff, buffpos) : lastIndexOfArray(expr, exprpos,
charpos, buff, buffpos);
if (offset < 0) {
return null;
}
// Copy the data from the source buffer into the result buffer
// to substitute the expression character
if (prevchr == MATCH_PATH) {
while (buffpos < offset) {
rslt[rsltpos++] = buff[buffpos++];
}
} else {
// Matching file, don't copy '/'
while (buffpos < offset) {
if (buff[buffpos] == '/') {
return null;
}
rslt[rsltpos++] = buff[buffpos++];
}
}
varsValues = addAndCreateList(varsValues, new String(rslt, 0,
rsltpos));
rsltpos = 0;
}
}
/**
* Get the offset of a part of an int array within a char array.
* This method return the index in d of the first occurrence after dpos of
* that part of array specified by r, starting at rpos and terminating at
* rend.
*
* @param r The array containing the data that need to be matched in d.
* @param rpos The index of the first character in r to look for.
* @param rend The index of the last character in r to look for plus 1.
* @param d The array of char that should contain a part of r.
* @param dpos The starting offset in d for the matching.
* @return The offset in d of the part of r matched in d or -1 if that was
* not found.
* @since 2.1.0
*/
protected int indexOfArray(int[] r, int rpos, int rend, char[] d, int dpos) {
// Check if pos and len are legal
if (rend < rpos) {
throw new IllegalArgumentException("rend < rpos");
}
// If we need to match a zero length string return current dpos
if (rend == rpos) {
return (d.length); // ?? dpos?
}
// If we need to match a 1 char length string do it simply
if ((rend - rpos) == 1) {
// Search for the specified character
for (int x = dpos; x < d.length; x++) {
if (r[rpos] == d[x]) {
return (x);
}
}
}
// Main string matching loop. It gets executed if the characters to
// match are less then the characters left in the d buffer
while (((dpos + rend) - rpos) <= d.length) {
// Set current startpoint in d
int y = dpos;
// Check every character in d for equity. If the string is matched
// return dpos
for (int x = rpos; x <= rend; x++) {
if (x == rend) {
return (dpos);
}
if (r[x] != d[y++]) {
break;
}
}
// Increase dpos to search for the same string at next offset
dpos++;
}
// The remaining chars in d buffer were not enough or the string
// wasn't matched
return (-1);
}
/**
* Get the offset of a last occurance of an int array within a char array.
*
* This method return the index in d of the last occurrence after dpos of
* that part of array specified by r, starting at rpos and terminating at
* rend.
*
* @param r The array containing the data that need to be matched in d.
* @param rpos The index of the first character in r to look for.
* @param rend The index of the last character in r to look for plus 1.
* @param d The array of char that should contain a part of r.
* @param dpos The starting offset in d for the matching.
* @return The offset in d of the last part of r matched in d or -1 if that
* was not found.
* @since 2.1.0
*/
protected int lastIndexOfArray(int[] r, int rpos, int rend, char[] d,
int dpos) {
// Check if pos and len are legal
if (rend < rpos) {
throw new IllegalArgumentException("rend < rpos");
}
// If we need to match a zero length string return current dpos
if (rend == rpos) {
return (d.length); // ?? dpos?
}
// If we need to match a 1 char length string do it simply
if ((rend - rpos) == 1) {
// Search for the specified character
for (int x = d.length - 1; x > dpos; x--) {
if (r[rpos] == d[x]) {
return (x);
}
}
}
// Main string matching loop. It gets executed if the characters to
// match are less then the characters left in the d buffer
int l = d.length - (rend - rpos);
while (l >= dpos) {
// Set current startpoint in d
int y = l;
// Check every character in d for equity. If the string is matched
// return dpos
for (int x = rpos; x <= rend; x++) {
if (x == rend) {
return (l);
}
if (r[x] != d[y++]) {
break;
}
}
// Decrease l to search for the same string at next offset
l--;
}
// The remaining chars in d buffer were not enough or the string
// wasn't matched
return (-1);
}
/**
* Matches elements of array r from rpos to rend with array d, starting from
* dpos.
* This method return true if elements of array r from rpos to rend equals
* elements of array d starting from dpos to dpos+(rend-rpos).
*
* @param r The array containing the data that need to be matched in d.
* @param rpos The index of the first character in r to look for.
* @param rend The index of the last character in r to look for.
* @param d The array of char that should start from a part of r.
* @param dpos The starting offset in d for the matching.
* @return true if array d starts from portion of array r.
* @since 2.1.0
*/
protected boolean matchArray(int[] r, int rpos, int rend, char[] d, int dpos) {
if ((d.length - dpos) < (rend - rpos)) {
return (false);
}
for (int i = rpos; i < rend; i++) {
if (r[i] != d[dpos++]) {
return (false);
}
}
return (true);
}
/**
*
* Inserts into a value wildcard-matched strings where specified.
*
*
* @param val The value to convert
* @param vars A Map of wildcard-matched strings
* @return The new value
* @since 2.1.0
*/
public static String convertParam(String val, Map vars) {
if (val == null) {
return null;
} else if (val.indexOf("{") == -1) {
return val;
}
Map.Entry entry;
StringBuilder key = new StringBuilder("{0}");
StringBuilder ret = new StringBuilder(val);
String keyTmp;
int x;
for (Iterator> i = vars.entrySet()
.iterator(); i.hasNext();) {
entry = i.next();
key.setCharAt(1, entry.getKey().toString().charAt(0));
keyTmp = key.toString();
// Replace all instances of the placeholder
while ((x = ret.toString().indexOf(keyTmp)) > -1) {
ret.replace(x, x + PLACEHOLDER_LENGTH, entry.getValue());
}
}
return ret.toString();
}
/**
* Adds and object to a list. If the list is null, it creates it.
*
* @param The type of the element.
* @param list The list.
* @param data The data to add.
* @return The list itself, or a new one if it is null.
*/
private List addAndCreateList(List list, T data) {
if (list == null) {
list = new ArrayList();
}
list.add(data);
return list;
}
/**
* Adds and object on top of a list. If the list is null, it creates it.
*
* @param The type of the element.
* @param list The list.
* @param data The data to add.
* @return The list itself, or a new one if it is null.
*/
private List addElementOnTop(List list, T data) {
if (list == null) {
list = new ArrayList();
}
list.add(0, data);
return list;
}
}