11. August 2014

Gradle PMD – Can’t find resource null

Gradle has support for PMD. You can find following example on internet:

apply plugin: 'pmd'

pmdMain {
  ruleSets = [ "basic", "strings" ]

This code is not working with Gradle 2.0. Here is error message:

:pmdMain FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':pmdMain'.
  Can't find resource null. Make sure the resource is a valid file or URL and is on the CLASSPATH. Here's the current classpath: C:\Users\georgik\tmp\install\gradle-2.0\lib\gradle-launcher-2.0.jar

The reason is simple. In case of Gradle 2.0 you must add language prefix before name of rule. You must use java-strings instead of plain strings.

Here is correct example (available also on YSoftDevs Github):

apply plugin: 'pmd'

pmdMain {
  ruleSets = [ "java-basic", "java-strings", "java-braces" ]

You can find more rules for PMD in official documentation.

Thanks Matt Sicker for correct solution.

23. June 2014

How to debug Gradle script

First of all: do not use daemon mode for debugging.

IntelliJ Idea is automatically spawning daemon when you start any Gradle task. You have to attach to remote process.

I wrote small “How to debug” based on info from forums.gradle.org.

You’ll need to set GRADLE_OPTS environment variable to:

-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005

Here is example in PowerShell:


$env:GRADLE_OPTS="-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005"

Configure Remote debugging in Idea:


You do not need to change anything in default configuration.

Now return to command line with your project and invoke task. Gradle will automatically stop and it waits for debugger.


Attach debugger


Here we go 🙂


There is small limitation. You can stop code execution outside DSL e.g. in class method (line 3). You won’t be able to stop execution in Gradle DSL line 10.

You can download sample build script from Github.

13. June 2014

Gradle Summit 2014 Lightning talk: Bamboo + Gradle

I had an opportunity to be one of Lightning talks speakers at Gradle Summit 2014 in Santa Clara – California.

I’d like to share with you slides from my talk about Bamboo and Gradle integration which we successfully deployed in Y Soft.

Link to Speaker Deck

It was exciting to hear about experience with Gradle from other speakers from companies like Netflix, Prezi or JFrog.

22. September 2013

Deploy Spring application by Maven to Tomcat7 via HTTPS – PKIX problem

Simple scenario: deploy spring application to remote server which has https management interface.

Easy task. When you have properly configured project with pom.xml then you can use tomcat7 plugin for Maven.

Part of pom.xml

  <!-- username and password must be set in ~/.m2/settings.xml -->
  <!-- URL where Maven can find Tomcat 7 Manager -->

Just run:

mvn tomcat7:deploy

Upload fails with error message:

PKIX path building failed

Ups. Not that easy? 🙂
The problem is that Java does not trust certificate of remote server.

Here is how to fix PKIX issue in Windows.

Open url of remote server by Firefox and save certificate to file.

Run PowerShell as administrator.

Go to directory with JDK cacets and import certificate. Default password is “changeit“.

cd C:\Program Files\Java\jdk1.7.0_40\jre\lib\security
keytool -import -alias test.sinusgear.com -keystore cacerts -file C:\Users\georgik\Documents\test.sinusgear.com

Done. Now you can start mvn tomcat7:deploy again.

1. June 2013

Tomcat installed as Windows service doesn’t create log files

I was chasing one very insidious bug. Tomcat installed as Windows service was not creating logs. The only log produced by Tomcat was stdout and stderr from procrun wrapper.

It was very weird. Tomcat downloaded from Apache’s website was creating logs without problem. There was no difference between directories of problematic Tomcat and working Tomcat.

Ok, let’s cut long story short. After several attempts to locate the bug I realized that Tomcat started by startup.bat was working correctly.

The only difference was in the Tomcat’s start method.

It was necessary to open Tomcat service properties (ES stands for Edit Service):

tomcat7w.exe \\ES\\tomcatweb

The tricky part here was not to check the Logging tab. This issue had nothing to do with stuff displayed in Logging tab. It was necessary to open Java tab.

When I compared working service and Tomcat service without logging I found that following lines were missing:



Somebody who was registering the service just omitted those lines when overriding –JvmOptions. It was sufficient to add java.util.logging.manager and config.file. Restart service and Tomcat was logging without problem.

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