node.java

来自「一个自然语言处理的Java开源工具包。LingPipe目前已有很丰富的功能」· Java 代码 · 共 50 行

package com.aliasi.dict;

import java.util.Arrays;

class Node {
    static final DictionaryEntry[] EMPTY_ENTRIES = new DictionaryEntry[0];
    static final char[] EMPTY_CHARS = new char[0];
    static final Node[] EMPTY_NODES = new Node[0];

    DictionaryEntry[] mEntries = EMPTY_ENTRIES;
    char[] mDtrChars = EMPTY_CHARS;
    Node[] mDtrNodes = EMPTY_NODES;
    Node getDtr(char c) {
        int i = Arrays.binarySearch(mDtrChars,c);
        return i < 0 ? null : mDtrNodes[i];
    }
    Node getOrAddDtr(char c) {
        Node dtr = getDtr(c);
        if (dtr != null) return dtr;
        Node result = new Node();
        char[] oldDtrChars = mDtrChars;
        Node[] oldDtrNodes = mDtrNodes;
        mDtrChars = new char[mDtrChars.length+1];
        mDtrNodes = new Node[mDtrNodes.length+1];
        int i = 0;
        for (; i < oldDtrChars.length; ++i) {
            if (oldDtrChars[i] > c) break;
            mDtrChars[i] = oldDtrChars[i];
            mDtrNodes[i] = oldDtrNodes[i];
        }
        mDtrChars[i] = c;
        mDtrNodes[i] = result;
        for (; i < oldDtrChars.length; ++i) {
            mDtrChars[i+1] = oldDtrChars[i];
            mDtrNodes[i+1] = oldDtrNodes[i];
        }
        return result;
        
    }
    void addEntry(DictionaryEntry entry) {
        DictionaryEntry[] oldEntries = mEntries;
        for (int i = 0; i < oldEntries.length; ++i)
            if (oldEntries[i].equals(entry)) return;
        mEntries = new DictionaryEntry[oldEntries.length+1];
        mEntries[0] = entry;
        System.arraycopy(oldEntries,0,mEntries,1,oldEntries.length);
    }
}