1.过滤字符串中的空白字符，可以移除tab，回车等空白字符

str.replaceAll("\\s+","");

str = str.replaceAll("(?i)[^a-zA-Z0-9\u4E00-\u9FA5]","");

public static String cleanFileName(String badFileName) {
	final int[] illegalChars = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,34,42,47,58,60,62,63,92,124};
	StringBuilder cleanName = new StringBuilder();
	for (int i = 0; i < badFileName.length(); i++) {
	    int c = (int)badFileName.charAt(i);
	    if (Arrays.binarySearch(illegalChars,c) < 0) {
	        cleanName.append((char)c);
	    }
	}
	return cleanName.toString();
}