String index error in Grails Google Charts plugin - mysql

Question

I have some strings that are in array form in a MySQL database that I want to use in the Grails Google Charts plugin, but I’m having trouble getting the plugin to accept them.
My strings look like [['string', 'Month'], ['number', 'Stories']] and [['April', 0], ['May', 0], ['June', 0], ['July', '12152']], which is the correct format, but I’m getting a "string index out of range error" that I'm trying to resolve.
I’m using g:set to set the variables and then passing them to gvisualization:
<g:each in="${groupsInstance.charts}" var="c">
<g:set var="chartColumns" value="${c.chartColumns}" />
<g:set var="chartData" value="${c.chartData}" />
<g:set var="chartType" value="${c.chartType}" />
<g:set var="chartDisplayKey" value="${chartType.chartKey}" />
<g:if test="${c.id == 1}">
<gvisualization:columnCoreChart elementId="${chartDisplayKey}"
width="${225}"
height="${225}"
legend="none"
columns="${chartColumns}"
data="${chartData}" />
</g:if>
</g:each>
When I try to do it this way, I get the following error in the app:
Error 500: Internal Server Error
URI: /appDash/groups/show/1
Class: java.lang.StringIndexOutOfBoundsException
Message: String index out of range: 2
And the console:
Error |
2014-08-12 12:36:51,717 [http-bio-8080-exec-6] ERROR errors.GrailsExceptionResolver - StringIndexOutOfBoundsException occurred when processing request: [GET] /app/groups/show/1
String index out of range: 2. Stacktrace follows:
Message: Error processing GroovyPageView: Error executing tag <gvisualization:columnCoreChart>: String index out of range: 2
If I initialize variables at the top of the page and use those instead, it works fine; the error occurs when I try to pull the strings out of the database. I’ve tried to find examples of the plugin being used this way without much success.