[WW-4138] OgnlTextParser contains a NPE when the expression is passed in as null

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3.15
• Fix Version/s: 2.3.16
• Assignee: Lukasz Lenart
• Reporter: David Greene
• Created: 11/Jul/13 16:44
• Updated: 08/Dec/13 17:21
• Resolved: 30/Jul/13 20:47

Description

Unfortunately, I haven't figured out the exact cause of the issue; however, the fix provided brings our system back to how it used to work.

When expression is passed in a null, a NPE is thrown @:

int start = expression.indexOf(lookupChars, pos);

        Object result = expression;
        int pos = 0;

        for (char open : openChars) {
            int loopCount = 1;
            //this creates an implicit StringBuffer and shouldn't be used in the inner loop
            final String lookupChars = open + "{";

            while (true) {
                int start = expression.indexOf(lookupChars, pos);
                if (start == -1) {
                    loopCount++;
                    start = expression.indexOf(lookupChars);
                }

Here is the fix I'm using in a locally built class file:

        Object result = expression = (expression == null) ? "" : expression;
        int pos = 0;

        for (char open : openChars) {
            int loopCount = 1;
            //this creates an implicit StringBuffer and shouldn't be used in the inner loop
            final String lookupChars = open + "{";

            while (true) {
                int start = expression.indexOf(lookupChars, pos);
                if (start == -1) {
                    loopCount++;
                    start = expression.indexOf(lookupChars);
                }

I can see about 10 different ways to 'fix' the issue, but this keeps the change to a single line since I don't entirely understand the workflow of what's going on.

FYI, it seems to have something to do with validate="true" on the form and when there are fields to validate which have nested getters, aka:

<@s.hidden key="myFakePatternHolder.pattern.id"/>