Eclipse Java debug mode: how to get actual type of value?

Question

The variable view of Eclipse Java Debug mode allows to inspect the values of variables. If the type of a variable has several sub-types, how to find out the actual type of the value?

Eclipse Standard/SDK

Version: Luna Service Release 1 (4.4.1) Build id: 20140925-1800

Answer 1

Use expressions view. If for example your variable name is x add x.getClass() to expressions view and see the type.

Answer 2

use ctrl+shift+I for inspect expressions/variables in debug mode of eclipse

let say i have below code

Example:

List<String> strLst = commonService.getUserdetail();

and i want to know value of strLst than

select commonService.getUserdetail() and than press ctrl+shift+I it will give you value that comes from commonService.getUserdetail() method

go HERE to know more about debuging in eclipse

Answer 3

This should be easier with Eclipse 4.17 (2020-09 release) :

Actual type in Variables view

The option Show Type Names in the Variables and Expressions views now displays the value's actual type instead of its declared type.
This simplifies debugging especially when variable details ( toString() ) is shown As the label for all variables .

To enable Show Type Names in the Variables view , column mode must be disabled ( View Menu > Layout > Show Columns ).

Example:

 Object s = "some string"; Collection<?> c = Arrays.asList(s, 1); // breakpoint