[Feature] Ignore invalid PREF parameter

[rfc2822]

There are some clients/servers which generate invalid VCard4 PREF parameters like this:

TEL;CELL=;PREF=:+12345

In this case, ez-vcard throws an IllegalStateException, making the whole VCard unusable:

java.lang.IllegalStateException: [Error 15] PREF parameter value is malformed and could not be parsed. Retrieve its raw text values instead by calling property.getParameters().get("PREF").

Would it be possible to ignore such errors, and continue to parse the VCard while ignoring the invalid PREF value? Maybe with an extra setting?

[mangstadt]

The code should have been checking for invalid PREF values, but it was not. Fixed in 157d5ca

[rfc2822]

Hello,

The problem still occurs when parsing VCards. You can use this test:

    @Test
    public void testInvalidPref() {
        VCard vCard = Ezvcard.parse("BEGIN:VCARD\r\n" +
                "VERSION:4.0\r\n" +
                "TEL;CELL=;PREF=:+12345\r\n" +
                "END:VCARD").first();
        assertEquals("+12345", vCard.getTelephoneNumbers().get(0).getText());
        assertNull(vCard.getTelephoneNumbers().get(0).getPref());
    }

getPref() then fails with an IllegalStateException, which is a runtime exception and thus unexpected.

[mangstadt]

This is expected behavior.

The vCard is parsed without error. Ezvcard.parse() executes without throwing an exception.

Upon calling getPref(), it tries to parse the PREF parameter's string value as an integer and cannot because the parameter value is an empty string.

I guess this should be documented in the Javadocs of Telephone#getPref(). It is documented in VCardParameters.getPref().

[rfc2822]

I see. I was just confused because of the runtime exception – maybe a checked InvalidValueException would be more safe, but I will try/catch the getPref(), thanks.

[mangstadt]

I wanted to use an unchecked exception because checked exceptions can clutter your code if overused. I'd also rather not create a new exception class to avoid cluttering the code base. 🤔