PhoneNumberUtil phoneUtil = PhoneNumberUtil.getInstance();
         PhoneNumber numberProto = phoneUtil.parse("phone_number", "");
        phoneUtil.isValidNumber(numberProto) == true ? "valid" : "phone no not valid"

if (setNum.matches(regexStr))
where regexStr can be:

//matches numbers only
String regexStr = "^[0-9]*$"

//matches 10-digit numbers only
String regexStr = "^[0-9]{10}$"

//matches numbers and dashes, any order really.
String regexStr = "^[0-9\-]*$"

//matches 9999999999, 1-999-999-9999 and 999-999-9999
String regexStr = "^(1\-)?[0-9]{3}\-?[0-9]{3}\-?[0-9]{4}$"

String regexStr = "^(?:(?:\+?1\s*(?:[.-]\s*)?)?(?:\(\s*([2-9]1[02-9]|[2-9][02-8]1|[2-9][02-8][02-9])\s*\)|([2-9]1[02-9]|[2-9][02-8]1|[2-9][02-8][02-9]))\s*(?:[.-]\s*)?)?([2-9]1[02-9]|[2-9][02-9]1|[2-9][02-9]{2})\s*(?:[.-]\s*)?([0-9]{4})(?:\s*(?:#|x\.?|ext\.?|extension)\s*(\d+))?$"

public static boolean isValidPhoneNo(CharSequence iPhoneNo) {
    return !TextUtils.isEmpty(iPhoneNo) &&
         Patterns.PHONE.matcher(iPhoneNo).matches();
}

String number = "012-1234567";
Pattern pattern = Pattern.compile("\d{3}-\d{7}");
Matcher matcher = pattern.matcher(number);
 if (matcher.matches()) {
      System.out.println("Phone Number Valid");
 }

/**
     * This method is used to set filter type of us phone number.
     * @param phone
     */
     public static void setFilterTypeOfUSPhoneNumber(final TextView phone){

            InputFilter filter = new InputFilter() {
                public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {
                        String pattern = "0123456789()- ";
                        for (int i = start; i < end; i++) {
                                if (pattern.indexOf(source.charAt(i)) < 0 ||
                                        source.length() > 14) {
                                        return "";
                                }
                        }
                        return null;
                }
            };

            phone.setFilters(new InputFilter[]{filter ,new InputFilter.LengthFilter(14)});
            phone.addTextChangedListener(new TextWatcher() {
                @Override
                public void onTextChanged(CharSequence s, int start, int before, int count) {}

                @Override
                public void beforeTextChanged(CharSequence s, int start, int count, int after) {}

                @Override
                public void afterTextChanged(Editable s) {

                    if(s.length() > 1){

                        if(s.length() < 5){
                            if(s.toString().indexOf("(") != 0 ||
                                    checkSpecialCharsPositions(s.toString())){
                                String str = s.toString();
                                str = replaceStrings(str);
                                str = "("+str;
                                s.clear();
                                s.append(str);
                                phone.setText(s);

                            }
                        }
                        else if(s.length() < 10){
                            if(s.toString().indexOf("(") != 0 ||
                                    s.toString().indexOf(")") != 4 ||
                                    checkSpecialCharsPositions(s.toString())){
                                String str = s.toString();
                                str = replaceStrings(str);
                                str = "("+str.substring(0, 3)+") "+str.substring(3);
                                s.clear();
                                s.append(str);
                                phone.setText(s);
                            }
                        }
                        else {
                            if(s.toString().indexOf("(") != 0 ||
                                    s.toString().indexOf(")") != 4 ||
                                    s.toString().indexOf("-") != 9 ||
                                    checkSpecialCharsPositions(s.toString())){

                                String str = s.toString();
                                str = replaceStrings(str);
                                str = "("+str.substring(0, 3)+") "+str.substring(3,6) + "-" + str.substring(6);
                                s.clear();
                                s.append(str);
                                phone.setText(s);
                            }
                        }
                    }
                    Selection.setSelection(s,s.length());
                }

                private String replaceStrings(String str){
                    str = str.replace("(", "");
                    str = str.replace(")", "");
                    str = str.replace(" ", "");
                    str = str.replace("-", "");
                    return str;
                }

                private boolean checkSpecialCharsPositions(String str){

                    return (str.indexOf("(") != str.lastIndexOf("(") ||
                            str.indexOf(")") != str.lastIndexOf(")") ||
                            str.indexOf("-") != str.lastIndexOf("-"));
                }
            });

        }