<plugins>
    <plugin>
        <groupId>com.atlassian.maven.plugins</groupId>
        <artifactId>maven-jira-plugin</artifactId>
        ...
        <configuration>
            ...
            <instructions>
                <DynamicImport-Package>
					...,
    				com.valiantys.nfeed.api;resolution:="optional"
                </DynamicImport-Package>
            </instructions>
...

import com.valiantys.nfeed.api.FieldDisplayResult;
import com.valiantys.nfeed.api.IFieldDisplayService;
import com.valiantys.nfeed.api.View;
import org.apache.felix.framework.FilterImpl;
import org.osgi.framework.BundleContext;
import org.osgi.util.tracker.ServiceTracker;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.annotation.Autowired;

public class ConnectAPIService implements InitializingBean, DisposableBean {

    @Autowired
    private BundleContext bundleContext;

    private ServiceTracker serviceTracker;

    /**
     * Gets the Connect field Issue rendering
     */ 
    public String getDisplayResult(long issueId, String customFieldId) throws ExocetException {
        IFieldDisplayService fieldDisplayService = getFieldDisplayService();
        FieldDisplayResult displayResult = fieldDisplayService.getDisplayResult(issueId, customFieldId);
        if (displayResult == null) {
            return null;
        }
        if (displayResult.hasError()) {
            // Throw exception or process error
			throw new RuntimeException(displayResult.getError());
        }
        return displayResult.getDisplay();
    }

    /**
     * Allows to chose the Connect field Issue rendering
     */ 
    public String getDisplayResult(long issueId, String customFieldId, View view) throws ExocetException {
        IFieldDisplayService fieldDisplayService = getFieldDisplayService();
        FieldDisplayResult displayResult = fieldDisplayService.getDisplayResult(issueId, customFieldId, view);
        if (displayResult == null) {
            return null;
        }
        if (displayResult.hasError()) {
            // Throw exception or process error
			throw new RuntimeException(displayResult.getError());
        }
        return displayResult.getDisplay();
    }

    public IFieldDisplayService getFieldDisplayService() {
        return (IFieldDisplayService) serviceTracker.getService();
    }

    @Override
    public void destroy() throws Exception {
        serviceTracker.close();
    }

    @Override
    public void afterPropertiesSet() throws Exception {
        final String filter = "(objectClass=" + IFieldDisplayService.class.getName() + ")";
        serviceTracker = new ServiceTracker(bundleContext, new FilterImpl(filter), null);
        serviceTracker.open();
    }
}