docs: public void accumulate(Object workingMemoryContext,
                             Object context,
                             Tuple leftTuple,
                             InternalFactHandle handle,
                             Declaration[] declarations,
                             Declaration[] innerDeclarations,
                             WorkingMemory workingMemory) throws Exception {
          Object value = this.unwrapHandle ? ((LeftTuple) handle.getObject()).getFactHandle().getObject() : handle.getObject();
          ((CollectContext) context).result.add( value );
      }