[stringtemplate-interest] basic question to template group

[Rabea Gransberger]

Dieter Frej schrieb:
> Hi,
> 
> what I wanted to do was to put all templates (all in all these are around 5 templates) in one physical file and use this file to generate my output. Following the great number of example on the Internet, I figured that I need a template group to realize my requirement
> 
> StringTemplateGroup stGroup = new StringTemplateGroup("mygroup", "C:\\Users\\xyz\\workspace");
> StringTemplate st = stGroup.getInstanceOf("junit");
> st.setAttribute("tests", ts); 
> System.out.println(st.toString());
> 
> I created the junit.st file and placed in the directory specified in the constructor of the StringTemplateGroup. In my junit.st I want to call another "template method"
> 
> junitclass(testheet) ::= <<
> 
> public class $tests.name$ {
> 	
> 	$m23ethod(rows=tests.rows)$
> 	
> }
> 
> Putting also
> 
> m23ethod(rows) ::= <<
> 	public void test() {
> $rows:{ u |
> 	$u.inputColumns; separator=", "$
> }$
> 
> in junit.st does not working. I get the following exception
> 
> Exception in thread "main" java.lang.IllegalArgumentException: Can't find template m23ethod.st; context is [junit]; group hierarchy is [mygroup]
> 
> Maybe I do not fully get template groups, but why am I required to create a separate template for each method I am calling? Or am I doing something wrong? (or totally missing the point? also possible ;-)

You've mixed up the possiblities to create StringTemplate Groups:
- You may group .st files in a directory
- You may create a group file (.stg) which contains all the templates.

Here's an example:
public class GroupFiles {

	public static void main(String[] args) throws IOException {
		StringTemplateGroup groupDir = new StringTemplateGroup("theGroup",
				"templates/group");

		final StringTemplate oneTemplate = groupDir.getInstanceOf("one");
		oneTemplate.setAttribute("class", GroupFiles.class);
		System.out.println(oneTemplate.toString());

		final FileReader reader = new FileReader("templates/group.stg");
		StringTemplateGroup groupFile = new StringTemplateGroup(reader);
		reader.close();
		
		final StringTemplate oneTemplate2 = groupFile.getInstanceOf("one");
		oneTemplate2.setAttribute("class", GroupFiles.class);
		System.out.println(oneTemplate2.toString());
	}

}

Using the following directory structure:
templates
   -group
    -- one.st
    -- two.st
   - group.stg

Contents of the files:
one.st:
------
$two(className=class.name)$
------

two.st:
------
$className$
------

group.stg:
-------
group theGroup;

one(class) ::= <<
<two(className=class.name)>
 >>

two(className) ::= <<
<className>
 >>
--------

Hope this made it a bit clearer.

Rabea