SimpleNumberReader.java

/**
 * Copyright 2007 The Apache Software Foundation
 *
 * 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.sohospace.dictionary.number;

import java.util.Arrays;
/**
 * @deprecated
 * @author Zhiliang Wang [qieqie.wang@gmail.com]
 *
 */
public class SimpleNumberReader implements NumberReader {

	public Number read(char[] input, int begin) {
		int pointer = begin;
		int count = 0;
		char[] buffer = null;
		for (char digit; pointer < input.length && (digit = isDigit(input[pointer])) != '\0'; pointer ++, count ++) {
			if (buffer == null) {
				buffer = new char[16];
			}
			if (count == buffer.length) {
				char[] newOne = new char[2 * buffer.length];
				System.arraycopy(buffer, 0, newOne, 0, count);
				buffer = newOne;
			}
			buffer[count] = digit;
		}
		//
		if (count == 0) {
			return null;
		}
		String numberValue = new String(buffer, 0, count);
		return new Number(numberValue, begin, pointer);
	}
	
	private final static char[] chars = new char[]{
			'��','��',
			'һ','Ҽ',
			'��','�E',
			'��','��',
			'��','��',
			'��','��',
			'��','�',
			'��','��',
			'��','��',
			'��','��',
	};
	private final static Char2Number[] sortedChars = new Char2Number[chars.length];
	private final static int charsLastIndex = chars.length - 1;
	static {
		final int mode = chars.length / 9;
		for (int i = 0; i < chars.length; i++ ) {
			sortedChars[i] = new Char2Number(chars[i], (char)('0' + (i/mode)));
		}
		Arrays.sort(sortedChars);
	}
	public static char isDigit(char ch) {
		if (ch >= '0' && ch <='9')
			return ch;
		if (ch < sortedChars[0].key || ch > sortedChars[charsLastIndex].key)
			return '\0';
		int index = Arrays.binarySearch(sortedChars, new Char2Number(ch, '\0'));
		if (index < 0) 
			return '\0';
		return sortedChars[index].number;
	}
	
	static class Char2Number implements Comparable<Char2Number> {
		
		char key;
		char number;
		
		public Char2Number(char key, char number) {
			super();
			this.key = key;
			this.number = number;
		}


		public int compareTo(Char2Number o) {
			return key - o.key;
		}
	}
	
}