private static char[] toChars(StringBuilder bufSentence) {
		char[] chs = new char[bufSentence.length()];
		bufSentence.getChars(0, bufSentence.length(), chs, 0);
		return chs;
	}
private static char[] toChars(StringBuilder bufSentence) {
		char[] chs = new char[bufSentence.length()];
		bufSentence.getChars(0, bufSentence.length(), chs, 0);
		return chs;
	}
private static char [ ] toChars ( StringBuilder bufSentence ) { char [ ] chs = new char [ bufSentence . length ( ) ] ; bufSentence . getChars ( 0 , bufSentence . length ( ) , chs , 0 ) ; return chs ; }
从 StringBuilder 里复制出 char[]
从 StringBuilder 里复制出 char []