Plugin doesnt load after restarting Jira exception is 'Given module class: java.lang.Void does not implement com.atlassian.jira.issue.customfields.CustomFieldType'

[CONRAD BRAGANZA]

Hi I created a simple plugin that extends SelectCFType. I got it to populate the customfieldoption and save the selected option value and then highlight the selected option value. I have noticed that when I stop restart the Jira, on restart the plugin gets disabled automatically, even if i enable it, the custom field created from it does not appear anymore. The ony way to get it working is to uninstall the plugin and reinstall it. Once I do this I cannot see the previous custom field say xyz created. The only way to get it only if I creat a new custom field say zzz. Once zzz is created both xyz and zzz appear. I scanned through the logs and the error I get is There was a problem loading the descriptor for module 'CustomDB Field' in plugin 'Customdb'.
Given module class: java.lang.Void does not implement com.atlassian.jira.issue.customfields.CustomFieldType

Not sure what the problem is

package com.xyz.jira.plugin;

import com.atlassian.jira.issue.customfields.impl.SelectCFType;
import com.atlassian.jira.issue.customfields.persistence.CustomFieldValuePersister;
import com.atlassian.jira.issue.customfields.converters.StringConverter;
import com.atlassian.jira.issue.customfields.converters.SelectConverter;
import com.atlassian.jira.issue.customfields.manager.OptionsManager;
import com.atlassian.jira.issue.customfields.manager.GenericConfigManager;
import com.atlassian.jira.issue.customfields.view.CustomFieldParams;
import com.atlassian.jira.issue.customfields.option.Options;
import com.atlassian.jira.issue.customfields.option.Option;
import com.atlassian.jira.issue.Issue;
import com.atlassian.jira.issue.search.SearchContextImpl;
import com.atlassian.jira.issue.fields.CustomField;
import com.atlassian.jira.issue.fields.config.FieldConfig;
import com.atlassian.jira.issue.fields.layout.field.FieldLayoutItem;
import com.atlassian.jira.util.ErrorCollection;

import java.util.Map;
import java.util.HashMap;

/**
*/
public class CustomDBPlugin extends SelectCFType {
/** The options manager. */
private final OptionsManager optionsManager;
//private DatabaseCFOption conf;

public CustomDBPlugin(CustomFieldValuePersister customFieldValuePersister, StringConverter stringConverter, SelectConverter selectConverter, OptionsManager optionsManager, GenericConfigManager genericConfigManager) {
super(customFieldValuePersister, stringConverter, selectConverter, optionsManager, genericConfigManager);
this.optionsManager = optionsManager;
}

/**
*/
@Override
public void validateFromParams(CustomFieldParams relevantParams,
ErrorCollection errorCollectionToAddTo, FieldConfig config) {
// do nothing, no validation required yet.
}

/**
*/
@Override
@SuppressWarnings("unchecked")
public Map getVelocityParameters(Issue issue, CustomField field,
FieldLayoutItem fieldLayoutItem) {
Map parameters = super.getVelocityParameters(issue, field, fieldLayoutItem);
FieldConfig fieldConfig = null;
if(issue == null)
{
fieldConfig = field.getReleventConfig(new SearchContextImpl());
} else
{
fieldConfig = field.getRelevantConfig(issue);
}
Options options = this.optionsManager.getOptions(fieldConfig);
if (options.isEmpty()) {
this.optionsManager.createOption(fieldConfig, null, new Long(1), "A");
this.optionsManager.createOption(fieldConfig, null, new Long(2), "B");
}
options = this.optionsManager.getOptions(fieldConfig);
Map<Long, String> results = new HashMap<Long, String>();
Long selectedId= (long) -1;
boolean selected = false;
Object value = field.getValue(issue);
if (value!=null) {
selected=true;
}
for (Option option : (Iterable<Option>) options) {
results.put(option.getOptionId(), option.getValue());
if (selected && value.toString().equals(option.getValue())) {
selectedId = option.getOptionId();
}
}
parameters.put("results", results);
parameters.put("selectedId", selectedId);
return parameters;
}


}

Here is the velocity template custom-db-field-edit.vm
#* @vtlvariable name="results" type="java.util.Map" *#
#* @vtlvariable name="selectedId" type="java.lang.String" *#
#controlHeader ($action $customField.id $customField.name $fieldLayoutItem.required $displayParameters.noHeader)


<select name="$customField.id" id="$customField.id" >
<option value="">Not selected</option>
#foreach ($mapEntry in $results.entrySet())
#if ( $selectedId == $mapEntry.key )
<option selected="selected" value="$mapEntry.key">$mapEntry.value</option>
#else
<option value="$mapEntry.key">$mapEntry.value</option>
#end
#end
</select>

#controlFooter ($action $fieldLayoutItem.fieldDescription $displayParameters.noHeader)

Here is the plugin desctiptor.

<atlassian-plugin key="com.xyz.jira.plugin.customdbplugin" name="CustomDB" plugins-version="2">
<plugin-info>
<description>xyx</description>
<version>1.0-SNAPSHOT</version>
<vendor name="XYZ" url="http://www.xyz.com/" />
</plugin-info>

<customfield-type key="customdb-field" name="CustomDB Field" class="com.xyz.jira.plugin.CustomDBPlugin">
<description>Custom DB Plugin</description>
<label>Custom DB Field</label>
<resource type="velocity" name="view" location="templates/plugins/custom-db/custom-db-field-edit.vm"/>
<resource type="velocity" name="edit" location="templates/plugins/custom-db/custom-db-field-edit.vm"/>
<resource type="velocity" name="xml" location="templates/plugins/fields/xml/xml-basictext.vm"/>
</customfield-type>

</atlassian-plugin>

[Radu Dumitriu]

Can you show us more from your exception ? Including the cause? It looks like a proxying error ...

[Colin Goudie]

Is your customfield-type class in the atlassian-plugin.xml really called com.xyz.jira.plugin.CustomDBPlugin? Or did you change that to post it here?

If so, can you paste the exact line from the source as I think this maybe the issue

[CONRAD BRAGANZA]

Hi Colin,

The cistomfield class "com.xyz.jira.plugin.CustomDBPlugin" It matches the fully qualified name of the class CustomDBPlugin shown above see the package definition "package com.xyz.jira.plugin" at the start of the class.

<customfield-type key="customdb-field" name="CustomDB Field" class="com.xyz.jira.plugin.CustomDBPlugin">
<description>Custom DB Plugin</description>
<label>Custom DB Field</label>
<resource type="velocity" name="view" location="templates/plugins/custom-db/custom-db-field-edit.vm"/>
<resource type="velocity" name="edit" location="templates/plugins/custom-db/custom-db-field-edit.vm"/>
<resource type="velocity" name="xml" location="templates/plugins/fields/xml/xml-basictext.vm"/>
</customfield-type>

[CONRAD BRAGANZA]

I have noticed that once the plugin is installed and a cusom field. The plugin does not get disbled on Jira startup. It only happens is when you create an issue and select one of the options and save it. So my logic might not be correct?

[CONRAD BRAGANZA]

Can someone tell me how to fix this i,e. how do I get the plugin to survive restarts. If existing issues use this plugin, then on restart this will not appear anymore unless it is detected and is very error prone.