PlayN showcase-html validation issue - eclipse

Question

I am new to both GWT and PlayN. Followed two installation guides from the PlayN wiki to get PlayN working in Eclipse: BeginnerInstallationGuide and GettingStarted. I can run the showcase-java project but the showcase-html version produces a problem during compiling, saying that it cannot find a validation jar. This is the output of the GWT compiler:
Compiling module playn.showcase.Showcase
Resolving com.google.gwt.validation.client.constraints.AbstractDecimalMaxValidator
Found type 'com.google.gwt.validation.client.constraints.AbstractDecimalMaxValidator'
Found type 'javax.validation.constraints.DecimalMax'
[WARN] Detected warnings related to 'javax.validation.Constraint'. Is validation-< version>.jar on the classpath?
Specify -logLevel DEBUG to see all errors.
[WARN] Ignoring unresolvable annotation type javax.validation.Constraint
Compiling 1 permutation
Compiling permutation 0...
Compile of permutations succeeded
Linking into C:\Users\Jo\playn-samples\showcase\html\target\playn-showcase-html-1.0-SNAPSHOT\showcase
Link succeeded
Compilation succeeded -- 62.900s
Would appreciate any help!

Answer 1

I don't have the answer,
but maybe try to clean and re-built the project "playn-showcase".
Also try to run "mvn package" (in eclipse: Run as... / Maven build... with goal 'package') for the project "playn-showcase" (explicitely not "playn-shocase-html").
This procedute probably creates the missing jar 'playn-showcase-html-1.0-SNAPSHOT.jar'.

Answer 2

Try adding the following dependencies to the showcase-html pom.xml if they don't already exist...
<dependencies>
...
<!-- not really needed, but will suppress errors during GWT compilation -->
<dependency>
<groupId>javax.validation</groupId>
<artifactId>validation-api</artifactId>
<version>1.0.0.GA</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.validation</groupId>
<artifactId>validation-api</artifactId>
<version>1.0.0.GA</version>
<classifier>sources</classifier>
<scope>provided</scope>
</dependency>
...
</dependencies>