Nesting ognl expressions?

[Nathan Russell]

I wonder if anyone can help.
I'm trying to create a new struts2 tag to render and operate as a 3 field date control. IE. a single jsp tag which results in 3 html input controls nicely laid out. Ignoring the complications of individual field validations (eg: month field is Feb, day field cant be > 28 unless year field is a leap year in which case it can be 29!). Anyway, ignoring that ..... I'm struggling with populating the value attribute.

I have a class which I'll use to store dates - its basically a wrapper around java.util.Date (I might use GregorianCalandar instead) which has getters and setters for day, month and year. In my action class I have a member variable whose type is my Date class, and I have a getter and setter for the field dob which gets and sets this member variable:

package mypackage;
public class Date {
	private java.util.Date m_date;
	
	public Date() {
		m_date = new java.util.Date();
	}
	
	public void setDay(int p_day) {
		m_date.setDate(p_day);
	}
	public int getDay() {
		return m_date.getDay();
	}

	public void setMonth(int p_month) {
		m_date.setMonth(p_month);
	}
	public int getMonth() {
		return m_date.getMonth();
	}
	
	public void setYear(int p_year) {
		m_date.setYear(p_year);
	}
	public int getYear() {
		return m_date.getYear();
	}

}

import mypackage.Date
public class AboutYou extends ActionSupport {
	private Date m_dob;
	
	public AboutYou() {
		m_dob = new Date();		
	}
	
	public String execute() {
		return "success";
	}
	
	public void setDob(Date p_dob) {
		m_dob = p_dob;
	}
	public Date getDob() {
		return m_dob;
	}	
}

I reference my tag like this:

<ss:datefield name="dob" label="%{getText('dobLabel')}" dayPostfix="/" monthPostfix="/" />

And my ftl looks like this:

		<span id="${parameters.id?html}_span_DAY" class="wwdatefield_DAY">
			<input type="text" name="${parameters.name?default("")?html}.day"<#rt/>
			<#if parameters.id??>
 id="${parameters.id?html}_DAY"<#rt/>
			</#if>
 value="problem area!"<#rt/>	
			/>
		</span>
		<span id="${parameters.id?html}_span_DAYPOSTFIX" class="wwdatefield_DAYPOSTFIX">
		<#if parameters.dayPostfix?default('')!=''>
			${parameters.dayPostfix?html}
		</#if>
		</span>

		<span id="${parameters.id?html}_span_MONTH" class="wwdatefield_MONTH">
		<#if parameters.month=='text'>
			<input type="text" name="${parameters.name?default("")?html}.month"<#rt/>
			<#if parameters.id??>
 id="${parameters.id?html}_MONTH"<#rt/>
			</#if>
 value="problem area!"<#rt/>	
			/>
		</span>
		<span id="${parameters.id?html}_span_MONTHPOSTFIX" class="wwdatefield_MONTHPOSTFIX">
		<#if parameters.monthPostfix?default('')!=''>
			${parameters.monthPostfix?html}
		</#if>
		</span>

		<span id="${parameters.id?html}_span_YEAR" class="wwdatefield_YEAR">
			<input type="text" name="${parameters.name?default("")?html}.year"<#rt/>
			<#if parameters.id??>
 id="${parameters.id?html}_YEAR"<#rt/>
			</#if>
 value="problem area!"<#rt/>	
			/>
		</span>

The bit I'm having a problem with is the value attribute of each of the fields (where in the code above I've written it as value="problem area!")
What I think I want to do is in the jsp pass an ognl reference to the action class's member variable:

<ss:datefield name="dob" label="%{getText('dobLabel')}" dayPostfix="/" monthPostfix="/" value="%{dob}" />

This I guess calls the action class's getDob method which will return the Date object. So then within the ftl I would want to do something like this:

value="${parameters.value}.day"

But I cant get this (or similar syntax) to work.
As usual, any pointers very much appreciated !

Cheers

Nathan

[David Newton]

Seems more a FreeMarker issue. ${parameters.value.day} doesn't work?

In any case, I'd check existing FreeMarker tags to see if anything has similar functionality.

[Nathan Russell]

Thanks for your reply David, but no, ${parameters.value.day} does not work - I get the following stack trace:

Expression parameters.value.day is undefined on line 19, column 11 in template/basic/date.ftl.
The problematic instruction:
----------
==> ${parameters.value.day} [on line 19, column 9 in template/basic/date.ftl]
 in include "/${parameters.templateDir}/basic/date.ftl" [on line 4, column 9 in template/divs/date.ftl]
----------

Java backtrace for programmers:
----------
freemarker.core.InvalidReferenceException: Expression parameters.nameValue.day is undefined on line 19, column 11 in template/basic/date.ftl.
	at freemarker.core.TemplateObject.assertNonNull(TemplateObject.java:124)
	at freemarker.core.Expression.getStringValue(Expression.java:118)
	at freemarker.core.Expression.getStringValue(Expression.java:93)
	at freemarker.core.DollarVariable.accept(DollarVariable.java:76)
	at freemarker.core.Environment.visit(Environment.java:209)
...

but if I simply use ${parameters.value} it returns mypackage.Date@805af4

So, as I see it, my object is being stored in the parameters map under the key 'value', and it is being returned correctly. Its just that for some reason I cant work out how to invoke the getDay() method?

Back to google I think !

Cheers

Nathan