001 /*
002 * Copyright (C) 2012 eXo Platform SAS.
003 *
004 * This is free software; you can redistribute it and/or modify it
005 * under the terms of the GNU Lesser General Public License as
006 * published by the Free Software Foundation; either version 2.1 of
007 * the License, or (at your option) any later version.
008 *
009 * This software is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * You should have received a copy of the GNU Lesser General Public
015 * License along with this software; if not, write to the Free
016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018 */
019
020 package org.crsh.vfs;
021
022 import org.crsh.util.BaseIterator;
023
024 import java.util.Iterator;
025 import java.util.NoSuchElementException;
026
027 public final class Path implements Iterable<String> {
028
029 /** . */
030 private static final String[] EMPTY_STRING = new String[0];
031
032 /** . */
033 private final boolean dir;
034
035 /** . */
036 private final String[] names;
037
038 /** . */
039 private String value;
040
041 public static Path get(Path parent, String name, boolean dir) {
042 if (!parent.dir) {
043 throw new IllegalArgumentException("Not a dir");
044 }
045 int length = parent.names.length;
046 String[] names = new String[length + 1];
047 System.arraycopy(parent.names, 0, names, 0, length);
048 names[length] = name;
049 return new Path(dir, names);
050 }
051
052 public static Path get(String s) {
053 if (s.length() == 0) {
054 throw new IllegalArgumentException("No empty path");
055 }
056 if (s.charAt(0) != '/') {
057 throw new IllegalArgumentException("Path " + s + " must begin with a '/'");
058 }
059
060 //
061 int start = 0;
062 int end = s.length();
063 String[] names = EMPTY_STRING;
064 while (start < end) {
065 if (s.charAt(end - 1) == '/') {
066 end--;
067 } else if (s.charAt(start) == '/') {
068 start++;
069 } else {
070 names = parseNames(s, start, end, 0);
071 break;
072 }
073 }
074
075 //
076 return new Path(end < s.length(), names);
077 }
078
079 private static String[] parseNames(final String s, final int prev, int end, final int count) {
080 int next = s.indexOf('/', prev);
081 if (next == -1 || next > end) {
082 if (prev < end) {
083 String[] ret = new String[count + 1];
084 ret[count] = s.substring(prev);
085 return ret;
086 } else {
087 return new String[count];
088 }
089 } else if (next - prev > 0) {
090 String[] ret = parseNames(s, next + 1, end, count + 1);
091 ret[count] = s.substring(prev, next);
092 return ret;
093 } else {
094 return parseNames(s, next + 1, end, count);
095 }
096 }
097
098 private Path(boolean dir, String[] names) {
099 this.dir = dir;
100 this.names = names;
101 }
102
103 public Iterator<String> iterator() {
104 return new BaseIterator<String>() {
105 int index = 0;
106 public boolean hasNext() {
107 return index < names.length;
108 }
109 public String next() {
110 if (index < names.length) {
111 return names[index++];
112 } else {
113 throw new NoSuchElementException();
114 }
115 }
116 };
117 }
118
119 public int getSize() {
120 return names.length;
121 }
122
123 public boolean isDir() {
124 return dir;
125 }
126
127 public String getName() {
128 return names.length > 0 ? names[names.length - 1] : "";
129 }
130
131 public boolean isChildOf(Path parent) {
132 if (parent.dir) {
133 int length = parent.names.length;
134 if (names.length == length + 1) {
135 for (int i = 0;i < length;i++) {
136 if (names[i].equals(parent.names[i])) {
137 return false;
138 }
139 }
140 return true;
141 }
142 }
143 return false;
144 }
145
146 @Override
147 public boolean equals(Object o) {
148 if (o == this) {
149 return true;
150 }
151 if (o instanceof Path) {
152 Path that = (Path)o;
153 int length = that.names.length;
154 if (names.length == length) {
155 for (int i = 0;i < length;i++) {
156 if (!names[i].equals(that.names[i])) {
157 return false;
158 }
159 }
160 return true;
161 }
162 }
163 return false;
164 }
165
166 @Override
167 public int hashCode() {
168 int hashCode = dir ? 1 : 0;
169 for (int i = names.length - 1;i >= 0;i--) {
170 hashCode = hashCode * 41 + names[i].hashCode();
171 }
172 return hashCode;
173 }
174
175 /**
176 * Returns the canonical path value.
177 *
178 * @return the value
179 */
180 public String getValue() {
181 if (value == null) {
182 StringBuilder sb = new StringBuilder(8 * names.length);
183 for (String name : names) {
184 sb.append('/').append(name);
185 }
186 if (dir) {
187 sb.append('/');
188 }
189 value = sb.toString();
190 }
191 return value;
192 }
193
194 public String toString() {
195 return "Path[value=" + getValue() + "]";
196 }
197 }