| /* |
| * Copyright 2000-2009 JetBrains s.r.o. |
| * |
| * Licensed 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 com.intellij.util.containers; |
| |
| import com.intellij.util.text.StringFactory; |
| |
| import java.util.ArrayList; |
| |
| public class CharTrie { |
| private ArrayList<Node> myAllNodes; |
| |
| private static class Node { |
| private final char myChar; |
| private final int myParent; |
| private IntArrayList myChildren; |
| |
| Node(int parent, char c) { |
| myChar = c; |
| myParent = parent; |
| } |
| } |
| |
| public CharTrie() { |
| init(); |
| } |
| |
| private void init() { |
| myAllNodes = new ArrayList<Node>(); |
| final Node root = new Node(-1, (char)0); |
| myAllNodes.add(root); |
| } |
| |
| public int size() { |
| return myAllNodes.size(); |
| } |
| |
| /** |
| * Returns reversed string by unique hash code. |
| */ |
| public String getReversedString(int hashCode) { |
| return StringFactory.createShared(getReversedChars(hashCode)); |
| } |
| |
| public String getString(int hashCode) { |
| return StringFactory.createShared(getChars(hashCode)); |
| } |
| |
| public int getHashCode(char[] chars) { |
| return getHashCode(chars, 0, chars.length); |
| } |
| |
| public int getHashCode(char[] chars, int offset, int length) { |
| int index = 0; |
| for (int i = offset; i < offset + length; i++) { |
| index = getSubNode(index, chars[i], true); |
| } |
| return index; |
| } |
| |
| public int getHashCode(CharSequence seq) { |
| int index = 0; |
| final int l = seq.length(); |
| for (int i = 0; i < l; i++) { |
| index = getSubNode(index, seq.charAt(i), true); |
| } |
| return index; |
| } |
| |
| public long getMaximumMatch(CharSequence seq, int offset, int length) { |
| int index = 0; |
| int resultingLength = 0; |
| while (length-- > 0) { |
| int nextIndex = findSubNode(index, seq.charAt(offset++)); |
| if (nextIndex == 0) { |
| break; |
| } |
| index = nextIndex; |
| resultingLength++; |
| } |
| |
| return index + (((long)resultingLength) << 32); |
| } |
| |
| public char[] getChars(int hashCode) { |
| int length = 0; |
| int run = hashCode; |
| while (run > 0) { |
| final CharTrie.Node node = myAllNodes.get(run); |
| length++; |
| run = node.myParent; |
| } |
| |
| char[] result = new char[length]; |
| run = hashCode; |
| for (int i = 0; i < length; i++) { |
| assert run > 0; |
| final CharTrie.Node node = myAllNodes.get(run); |
| result[length - i - 1] = node.myChar; |
| run = node.myParent; |
| } |
| |
| return result; |
| } |
| |
| public int getHashCodeForReversedChars(char[] chars) { |
| return getHashCodeForReversedChars(chars, chars.length - 1, chars.length); |
| } |
| |
| public int getHashCodeForReversedChars(char[] chars, int offset, int length) { |
| int index = 0; |
| while (length-- > 0) { |
| index = getSubNode(index, chars[offset--], true); |
| } |
| return index; |
| } |
| |
| public char[] getReversedChars(final int hashCode) { |
| int length = 0; |
| int run = hashCode; |
| while (run > 0) { |
| final CharTrie.Node node = myAllNodes.get(run); |
| length++; |
| run = node.myParent; |
| } |
| |
| char[] result = new char[length]; |
| run = hashCode; |
| for (int i = 0; i < length; i++) { |
| assert run > 0; |
| final CharTrie.Node node = myAllNodes.get(run); |
| result[i] = node.myChar; |
| run = node.myParent; |
| } |
| |
| return result; |
| } |
| |
| public int findSubNode(int parentIndex, char c) { |
| return getSubNode(parentIndex, c, false); |
| } |
| |
| private int getSubNode(int parentIndex, char c, boolean createIfNotExists) { |
| CharTrie.Node parentNode = myAllNodes.get(parentIndex); |
| if (parentNode.myChildren == null) { |
| if (!createIfNotExists) { |
| return 0; |
| } |
| parentNode.myChildren = new IntArrayList(1); |
| } |
| IntArrayList children = parentNode.myChildren; |
| int left = 0; |
| int right = children.size() - 1; |
| while (left <= right) { |
| int middle = (left + right) >> 1; |
| int index = children.get(middle); |
| CharTrie.Node node = myAllNodes.get(index); |
| int comp = node.myChar - c; |
| if (comp == 0) { |
| return index; |
| } |
| if (comp < 0) { |
| left = middle + 1; |
| } |
| else { |
| right = middle - 1; |
| } |
| } |
| if (!createIfNotExists) { |
| return 0; |
| } |
| |
| int index = myAllNodes.size(); |
| children.add(left, index); |
| myAllNodes.add(new CharTrie.Node(parentIndex, c)); |
| return index; |
| } |
| |
| public void clear() { |
| init(); |
| } |
| } |