How to manipulate contents prior to checkout

hwr

Hi All,

We want to capture check out event, manipulate the contents of the document being checked out (say for example encrypt the contents) and allow user to check out such modified contents.

In order to achieve this, we wrote a TBO to capture checkout event and in that TBO we got access to IDFCheckoutOperation (clientX.getxxxOperation). We got content of the object being checked out, manipulated the contents the way wanted. We executed add and execute methods on checkoutOperation.

What we found out was, the execute operation calls back doCheckout method. This becomes a recursive call causing stack overflow.

My question ... is there a way to achieve what we want to do?

Another question is... This implementation (if it succeeds) may cause the user to checkout a different file than he intends to checkout. How can we address this situation?

Thanks in advance,

PanfilovAB

What we found out was, the execute operation calls back doCheckout method. This becomes a recursive call causing stack overflow.

Are you a friend of ?

First off all, you should clearly understand that TBO checkout() method does nothing but updates r_lock_owner, r_lock_date, r_lock_machine fields. So, overriding wthat method does not solve your problem. IDfCheckoutOperation is just a client helper that at first calls checkout() and then calls getContent() or getFile() methods. So, you should override getContentEx3() and getFileEx2() method and make sure that you custom code is fired inside IDfCheckoutOperation only, smth. like:

@Override
public synchronized ByteArrayInputStream getContentEx3(String format, int page, String pageModifier, boolean other) throws DfException {
    ByteArrayInputStream bais =  super.getContentEx3(format, page, pageModifier, other);
    if (isInsideCheckOutOperation()) {
        //custom code that reads bais and returns encrypted ByteArrayInputStream
    } else {
        return bais;
    }
}
@Override
public synchronized String getFileEx2(String fileName, String formatName, int page, String pageModifier, boolean other) throws DfException {
    String path= super.getFileEx2(fileName, formatName, page, pageModifier, other);
    if (isInsideCheckOutOperation()) {
        //custom code that read path and modifies it
    } else {
        return path;
    }
}
protected final boolean isInsideCheckOutOperation() {
    StackTraceElement[] ste = new Exception().getStackTrace();
    Set<String> knownClasses = new HashSet<String>();
    knownClasses.add("com.documentum.operations.outbound.DfCheckoutOperation");
    knownClasses.add(".....");
    for (StackTraceElement e : ste) {
        for (String className : knownClasses) {
            if (e.getClassName().startsWith(className)) {
                return true;
            }
        }
    }
    return false;
}