Groovy 'as' keyword to implement 2+ interfaces

Question

Dear All:

I would like to implement a Glazed List that has both an AdvancedTableFormat and WritableTableFormat interface.

I am reading here: http://www.jroller.com/aalmiray/entry/glazedlists_groovy_not_your_regular

and for one interface it seems this is possible in Groovy with the "as" keyword:

# return new EventTableModel(linksList, [  
#       getColumnCount: {columnNames.size()},  
#       getColumnName: {index -> columnNames[index]},  
#       getColumnValue: {object, index ->  
#          object."${columnNames[index].toLowerCase()}"  
#       }] as TableFormat)

Is it somehow possible to do this for two interfaces? If so how?

Thank you!

Misha

Answer 1

You can create a new interface that extends the two interfaces you are interested in.

interface PersonalizedTableFormat extends AdvancedTableFormat, WriteableTableFormat {
}

You can cast the object you return to the new interface.

return object as PersonalizedTableFormat;

Answer 2

The "as" keyword is just a fancy way of invoking Groovy's asType(Class) method, which takes only a single Class as an argument. Therefore you can't directly use "as" with more than one interface (unless you take frm's approach and combine the interfaces in one super interface).