// 过滤整数字符，把所有非0～9的字符全部删除
private void filterInt(StringBuilder builder) {
for (int i = builder.length() - 1; i >= 0; i--) {
int cp = builder.codePointAt(i);
if (cp > '9' || cp < '0') {
builder.deleteCharAt(i);
}
}
}
public void insertString(FilterBypass fb, int offset, String string, AttributeSet attr)
throws BadLocationException {
StringBuilder builder = new StringBuilder(string);
for (int i = builder.length() - 1; i >= 0; i--) {
int cp = builder.codePointAt(i);
if (!Character.isDigit(cp) && cp != '-') {
builder.deleteCharAt(i);
if (Character.isSupplementaryCodePoint(cp)) {
i--;
builder.deleteCharAt(i);
}
}
}
super.insertString(fb, offset, builder.toString(), attr);
}