How to find a "FieldRead" expression without "this." in class internal functions on Java.

[ZQ-Struggle]

How to identify a 'FieldRead' expression without the 'this' keyword in a Java class's internal functions? I am attempting to locate a 'FieldRead' expression within an internal function of a class. However, during coding, the 'this' keyword was omitted, as 'fruitMap' shows in the following figure.

If the source code uses the expression "this.fruitMap", it is easy to locate the corresponding field read. However, I am not sure how to identify the field read when "this" is omitted.
Please tell me the correct way to do so!!!

[Aurora-yzj]

I've come across a similar problem. Hope somebody could help with this issue, I'll be really appreciated!

[ZQ-Struggle]

I find a solution from this issue. It works, but I'm not sure it is the right way.
#10980
The key point is that the predicate 'getQualifier' does not consider the FieldRead expression without the 'this' keyword. However, 'getFieldQualifier' in 'semmle.code.java.dataflow.internal.DataFlowNodes::Public' provides such a feature. It utilizes the 'ImplicitInstanceAccess' class to locate the FieldRead that implicitly accesses an internal property.
It is a solution learned from another question. If anyone can provide a better solution, I would be grateful.

[atorralba]

If you want to access the implicit qualifier of the field access for dataflow purposes (e.g. find accesses to fields of a certain type), this is the correct way of doing it. If you just want to access the field read, see @jketema answer below.

[ZQ-Struggle]

Thank you! Actually, both of two expression is essential to me.

[jketema]

Hi @ZQ-Struggle,

Thanks for your question. To locate all field reads without a qualifier (i.e., with an implicit this). You can do the following:

import java

from FieldRead v
where not exists(v.getQualifier())
select v

[ZQ-Struggle]

Thanks a lot for illustration.