StringTemplate-4: Cannot render expr property

Question

According to the StringTemplate 4 wiki, I should be able to display an expr property, but I cannot. I'm using StringTemplate4 with jython.

Here's my template file, test.st:

test(persons, person) ::= <<
<table>
    <tr><th>Name</th><th>Age</th></tr>
    <tr><td>$person.name$</td><td>$person.age$</td></tr>
    $persons:{p|<tr><td>$p.name$</td><td>$p.age$</td></tr>}$
</table>

Here's my jython code. When I try to render the template, the name and age values are not shown.

>>> import org.stringtemplate.v4 as st
>>> 
>>> class Person:
...     def __init__(self, name, age):
...         self.name = name
...         self.age = age
... 
>>> group = st.STGroupDir('~/template', '$', '$')
>>> tmpl = group.getInstanceOf('test')
>>> 
>>> tmpl.add('persons', [Person('jim', 25), Person('sam', 46)])
/test()
>>> tmpl.add('person', Person('bob', 55))
/test()
>>> 
>>> print tmpl.render()
<table>
    <tr><th>Name</th><th>Age</th></tr>
    <tr><td></td><td></td></tr>
    <tr><td></td><td></td></tr><tr><td></td><td></td></tr>
</table>

In the interpreter, I can access the attributes in tmpl fine.

>>> tmpl.attributes
{person=<__main__.Person instance at 0x54>, persons=[<__main__.Person instance at 0x55>, <__main__.Person instance at 0x56>]}
>>> p = tmpl.getAttribute('person')       
>>> print p.name, p.age
bob 55
>>> for p in tmpl.getAttribute('persons'):
...     print p.name, p.age
... 
jim 25
sam 46

Any idea why this doesn't work? Am I doing something wrong? I also tried creating getName() and getAge() methods for the Person class without luck. If I create a data aggregate I'm able to access the properties fine.

Answer 1

In Java, it would be because those properties are not public. How does Jython handle access to fields?