I'm wondering if it is an accepted practice or not to avoid multiple calls on the same line with respect to possible NPEs, and if so in what circumstances. For example:

getThis().doThat();

vs

Object o = getThis();
o.doThat();

The latter is more verbose, but if there is an NPE, you immediately know what is null. However, it also requires creating a name for the variable and more import statements.

So my questions around this are:

• Is this problem something worth designing around? Is it better to go for the first or second possibility?
• Is the creation of a variable name something that would have an effect performance-wise?
• Is there a proposal to change the exception message to be able to determine what object is null in future versions of Java ?