Saturday, December 5, 2015

Whirlwind Tour of JavaOne and Oracle Openworld 2015

JavaOne 2015 Roundups and Summary Articles

I recently had the wonderful opportunity of attending JavaOne and Oracle Openworld 2015 and have extensively blogged about the social and technical aspects of the conference!

Get a taste of the many events and exhibits on display and an insider's view on the conference.  I will also be presenting the most important takeaways regarding the future direction of Java including an in-depth discussion of changes coming in Java 9 and how to best prepare for those upcoming changes.

If you are local to the Richmond,VA then check out our meetup on the topic!

JavaOne 2015 Day 1 Roundup

JavaOne 2015 Day 2 Roundup

JavaOne 2015 Day 3/4 Roundup

More Pictures of JavaOne 2015

You can find more pictures of the event in our JavaOne 2015 Album here: JavaOne 2015

We had a great time celebrating 20 years of #java at the JavaOne Conference and Oracle OpenWorldBig thanks to Atlassian for providing refreshments at Duke's Cafe and Buzzhouse#JavaOne #JavaOne2015 #oow15

Posted by Ippon Technologies USA on Tuesday, November 3, 2015

Whirlwind tour of Javaone Meetup


Link to slides: Slides for RJUG JavaOne meetup

Friday, September 11, 2015

Running a new jHipster Application using Compass and the main CSS file is not loading

How to fix a Newly Created jHipster Application not Loading the Main CSS File 

If you see an error similar to the following upon first startup of a jHipster application you have just created:

Failed to load resource: the server responded with a status of 404 (Not Found)

Issue loading main.css on jHipster application
jHipster with CSS not loaded

Then you will need to run the grunt task, grunt compass.

Install Compass

You will need to first install Compass, an open-source CSS Authoring Framework before you can run the Grunt task to create the main.css file which is missing.

Using node:

npm install compass

Reference the following link for more info about installing compass using npm

Run Grunt Task

After you install Compass, you will then need to run the grunt task.  In in IntelliJ you can click the grunt task runner at the bottom of your screen or go to Tools -> Open Grunt Console.

Use grunt task runner console to create Main CSS file
Run grunt compass task to create main.css file

Restart your Application

Try refreshing and restarting your application and the styling should now display correctly.

mvn spring-boot:run

Saturday, August 15, 2015

Spring Scheduler to Create Background Process to make Async Calls to Update Cache in Spring Boot

Using Spring Scheduler to Create a Scheduled Task that hits your Endpoints to Update a Spring Cache for a Spring Boot Application

I used Spring Scheduler to execute a process on a regular basis to make separate async calls to several endpoints to keep the Spring cache updated and also as a health monitor.

This serves two purposes for us, we monitor all the endpoints to ensure correct data is coming back and it keeps the caches fresh and up to date even when there hasn't been traffic on that endpoint recently.

Guides on how to setup Spring caching:

Guide on Spring Scheduler:

Spring Scheduler

You will want to add 3 annotations to your class.  You will need to add annotations for caching, async method calls and scheduling.

Add annotations to your Application.Java class for caching, async and scheduling
Add annotations to your Application.Java class

Create Scheduled Task

I created a scheduled task here and set the interval that it runs on using Spring Scheduler and the @Scheduled annotation.

The task calls a method which is async and cached which allowed me to call multiple endpoints concurrently.  The results of the method call were cached and the success was logged.

I also injected the service to call the async method we are using to get the status of various endpoints.

Create Service for Scheduled Task to use

Get endpoint status is the method called directly from the scheduled task.  You can pass in a constant or enum to indicate which endpoint you want to check.  Each endpoint will be cached separately because the parameters in the method call are different.

You will need to setup caching in a separate config file.  You can view this article on how to setup Spring caching:

Get endpoint status will then call the correct getStatus() method to check the results of the endpoint.  These results will be cached.

This scheduled task can be used with an API or service to regularly check the status and response of various endpoints for health checking or as a regular running integration test of sorts.

View full code below

View the code on Github here:

Code snippets below:

Wednesday, July 29, 2015

Add Guava Cache to Spring Boot to Cache Method Calls

Add Google Guava Cache to Spring Boot to Cache the Results of Method Calls using Java Config and Spring Annotations

If you have a time-intensive method that is slowing down your application and the results of that method don't change very often, it is a good candidate for caching.  This guide will show you how to implement caching in your Spring Boot application using Google Guava cache.  

Guava cache is a simple, lightweight in-memory cache that has more configuration options then the default In-Memory Spring Cache.  Guava cache is not for clustered systems, for that you will want to use Hazelcast

So if you just need a simple cache but you want more config options such as cache expiration time, then this approach may fit your use case.  Alternatively, you could use EhCache.

Full source code references can be found at the bottom of the article.

More info on Guava Cache:

More info on Spring Cache:

Add dependencies to your Maven pom.xml file

Add the two following dependencies to your maven pom file and clean and package your dependencies.  You will need to add Guava and a Spring library that contains helper methods and classes for configuring the cache.

Add dependencies to your pom.xml for google guava cache and helper spring methods
Add dependencies to your pom.xml for guava cache

Create CacheConfig file

You need to create a CacheConfig file to configure the cache using Java config.  Create this config file as a separate class implementing CachingConfigurer and place it in your config folder with your other Java config classes.

Add Cache Manager and setup Guava Cache
Add Cache Manager and setup Guava Cache

Add Cacheable annotation to method to be cached

You will need to add the @Cacheable annotation and pass in the name of the cache which will be used for that method.

If your method has a passed in parameter, results for each different parameter will be cached.  So, each time a new parameter is passed in, this will execute the method and place the results in the cache.  Future calls using that parameter will pull results from the cache and skip execution of the method.

Add Cacheable annotation to the method to be cached
Add Cacheable annotation to the method to be cached

Add Endpoint to Clear Cache on Demand

You will also probably want to add an endpoint to easily refresh the cache.  You can do this by adding an endpoint to a controller with the @CacheEvict annotation.

This method will completely clear the cache.  All future requests will execute the method until the cache is populated again.

You may want to protect this endpoint using basic security implemented through Spring Security

Add an endpoint to clear the cache
Add an endpoint to clear the cache

Other considerations and Source Code

You may want to initially warm the cache and call the method with all possible parameters such that even initial users access the cached version.

You can view the complete source code here:

Friday, May 15, 2015

Spring Boot Internationalization with Default Locale for Message Strings

How to add Spring Boot Internationalization with Default Locale for Storing Message Strings such as Validation Messages in a file 

 This article will show you how to use a properties file to define static text in your application such as for validation message.

All the code is appended at the bottom of the article. 

Add Default locale and Message Source beans to your Application class 

 Add these classes to set your default locale and configure the location of your message properties file

Add beans to your Spring Boot Application class
Add locale and MessageSource beans to your Application Class

Add a Service and Interface to retrieve message text 

 This service will pull the default locale from the session and then get the message text from your properties file using the messageSource.

Create Service to get messages by locale
Add a service to get the msgs in your props file

In your controller, use the Message service to get the message text 

 You will inject the message service in the controller and then pass in the id to get the value from the props file

Inject svc and get message from i18n props file
Inject service into your controller and get the message

Create the file in the locale folder 

 In resources, create the locale folder and then create a file called

Create localized message props file
Create message properties file

Review the code here

You can view all the code here: Link to Github Gist here

Thursday, May 7, 2015

Change Port on a Spring Boot Application when using intelliJ

Change Port on a Spring Boot Application when using intelliJ 

Two ways to change the port that the embedded Tomcat is using in a Spring Boot Application.

The first way is to modify the application properties in the resources folder:

Update application properties to change port
Update application props in Spring Boot Application

There are a couple issues with this approach.  You might only want this port change in your local environment and if you check it in by accident you might break things.

Alternatively, you can use a command line parameter.

Go to Run -> Edit Configurations -> VM options

Then enter in the following argument:


Then click apply and OK and attempt to run the application again.

Update port on Spring Boot application using VM option
Update port using VM option

Tuesday, April 7, 2015

Convert Multiple Tasks to Sub-Tasks in JIRA similar to Bulk Update using Script Runner

How to Convert A Large Number of JIRA Tasks into Sub-Tasks using the Adaptavist Script Runner Plugin with JIRA

In JIRA, there is no way to convert Tasks into Sub-Tasks using the built-in Bulk Update functionality.  The lack of the feature is described in many JIRA tickets and Confluence posts on the official Atlassian site such as the two listed below:

There are many potential workarounds to this such as using selenium scripting to automate the conversion process using browser automation.  The best solution I have found is to use scripting within JIRA.

Backup your System

Before you attempt this, you should backup your JIRA instance because you potentially can make changes to tasks you did not intend.

Go to System settings and scroll down to the IMPORT & EXPORT section:

Use JIRA Backup functionality
Backup your JIRA instance

Install JIRA Adaptavist Scriptrunner

Scriptrunner by Adaptavist
Scriptrunner by Adaptavist

Download Adaptavist Scriptrunner

Get Adaptavist Scriptrunner:

The file will be named something like this: groovyrunner-3.0.6.jar...

Upload and Install Scriptrunner
Upload your downloaded JIRA plugin as a JAR File
Upload your downloaded JIRA plugin as a JAR File

Open up Scriptrunner and run the script

Here is the script you want to run. This version uses a custom JQL query to find a comma delimited list of items that have certain values in a custom Functional Requirement field. It then loops through the list of issues and converts them to a subtasks then links the task to the parent task.
import com.atlassian.jira.component.ComponentAccessor
import com.atlassian.jira.jql.parser.JqlQueryParser
import com.atlassian.jira.web.bean.PagerFilter
import com.atlassian.jira.ComponentManager
import com.atlassian.jira.event.type.EventDispatchOption
import com.atlassian.jira.issue.Issue;
import com.atlassian.jira.issue.MutableIssue;
import com.atlassian.jira.component.ComponentAccessor;
import com.atlassian.jira.user.ApplicationUser;
import com.atlassian.jira.issue.UpdateIssueRequest;

//Examples, 8 is my subtask issue type id. Will be different for others
//changeToSubTaskAndLink("AXDIS-509", "AXDIS-1045", "8")
//changeToSubTaskAndLink("AXDIS-509", "AXDIS-1046", "8")

def jqlQueryParser = ComponentAccessor.getComponent(JqlQueryParser.class)
def searchProvider = ComponentAccessor.getComponent(SearchProvider.class)
def issueManager = ComponentAccessor.getIssueManager()
def user = ComponentAccessor.getJiraAuthenticationContext().getUser()

//Add first function req here
//issueKey = 'AR-1231' for searching by id
def queryParamsString = "'Functional Requirement Id' ~ 5.3 " 

//Add all functional reqs after the first here
def functionalReqs = ['5.4', '5.5', '5.6', '5.7', '5.8', '5.9', '5.10', '5.11', '5.12']

functionalReqs.eachWithIndex { a, i ->
  queryParamsString += " OR 'Functional Requirement Id' ~ " + a

def parentIdKey = "AR-2125"
def subTaskIssueTypeId = "5"

def query = jqlQueryParser.parseQuery("project = AR AND affectedVersion = "Phase 2" AND 'Business Requirement Id' ~ '5' AND (" + queryParamsString + ")")
def results =, user, PagerFilter.getUnlimitedFilter())
results.getIssues().each {documentIssue ->
    // if you need a mutable issue you can do:
    def issue = issueManager.getIssueObject(
    // do something to the issue...
    //changeToSubTaskAndLink("AR-2125", "AR-1977", "5")
    changeToSubTaskAndLink(parentIdKey, documentIssue.key, subTaskIssueTypeId)

//Method to do all the work
def changeToSubTaskAndLink(parentId, childId, subTaskIssueTypeId)
{  //Get the parent Issue 
    def parent = ComponentManager.getInstance().getIssueManager().getIssueObject(parentId) 
 //Get the child Issue 
    MutableIssue child = (MutableIssue)ComponentManager.getInstance().getIssueManager().getIssueObject(childId) 
    //Change the child to the subtask type 
    //Update the issue 
    ComponentAccessor.getIssueManager().updateIssue((ApplicationUser)ComponentManager.getInstance().jiraAuthenticationContext?.user, (MutableIssue)child, UpdateIssueRequest.builder().build())

    //Create the subtask link, if this is not done you'll end up with orphans 
    //ComponentManager.getInstance().getSubTaskManager().createSubTaskIssueLink(parent, child, ComponentManager.getInstance().jiraAuthenticationContext?.user) 
    ComponentAccessor.getSubTaskManager().createSubTaskIssueLink(parent, child, ComponentAccessor.getJiraAuthenticationContext().getLoggedInUser())