如何强制EditText只接受特定的字母数字字符？

import android.text.InputFilter;
import android.text.Spanned;
import android.text.TextUtils;

public class AlphaNumericInputFilter implements InputFilter {
    private final String mAcceptedChars;

    public AlphaNumericInputFilter(String acceptedChars) {
        mAcceptedChars = acceptedChars;
    }

    @Override
    public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {
        if (TextUtils.isEmpty(mAcceptedChars)) {
            return null; // 如果没有指定特定字符，不做任何限制
        }

        StringBuilder filteredBuilder = new StringBuilder();
        for (int i = start; i < end; i++) {
            char c = source.charAt(i);
            if (Character.isLetterOrDigit(c) && mAcceptedChars.contains(String.valueOf(c))) {
                filteredBuilder.append(c);
            }
        }
        boolean hasFiltered = filteredBuilder.length() != (end - start);
        return hasFiltered ? filteredBuilder.toString() : null;
    }
}

EditText editText = findViewById(R.id.editText);
editText.setFilters(new InputFilter[]{new AlphaNumericInputFilter("ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")});