build.xml throw NPE

General
1

I’m starting Vaadin development for the first time (6.8). I’m starting to the build.xml to run. I get a NPE at line 434 which on my version looks like this:


        <!-- These should go to various JARs -->
        <copy todir="${output-dir}/WebContent">
            <filterchain>
                <expandproperties />
                <replacetokens begintoken="@" endtoken="@">
                    <token key="version" value="${version.full}" />
                </replacetokens>
                <replacetokens begintoken="@" endtoken="@">
                    <token key="version-minor" value="${version.major}.${version.minor}" />
                </replacetokens>
                <replacetokens begintoken="@" endtoken="@">
                    <token key="builddate" value="${build.date}" />
                </replacetokens>
                <replacetokens begintoken="@" endtoken="@">
                    <token key="gwt-version" value="${gwt-version}" />
                </replacetokens>
            </filterchain>
            <fileset dir="WebContent">
                <exclude name="**/.svn" />
                <include name="release-notes.html" />
                <include name="license.html" />
                <include name="css/**" />
                <include name="img/**" />
            </fileset>
        </copy>

Since this isn’t Java code but an Ant script, I don’t know how to debug it. Can anyone help me?

Edit: this happens when I run with a target of compile-wigetset.

2

It is still unclear to me whether you want to develop applications or extensions for Vaadin or whether you want to make larger modifications to the core library.

In the former case, you should not try to use a checkout or the build script of Vaadin itself - you just need the JAR. See e.g.
Book of Vaadin
.

In the latter case, see
this page
.

Note that even for small extensions to the core, it is usually not necessary to have a checkout of Vaadin itself but just take the JAR and put any modified copies of Vaadin classes in your project and before Vaadin JAR on the classpath.

3

I am trying to contribute to the Vaadin open source project. I have read the Start Development page; that’s why I’m trying to build the widgets. It’s part of what the page says to do.

4

The target compile-widgetset is not a “top-level target” in the sense that it does not perform all necessary initialization etc.

The targets you should be using directly are probably a subset of:

  • package-jar
  • defaulttheme
  • widgetset-default
  • widgetsets
  • package-war
  • package-all

Many of the others are internal targets and some others depend on our build and test infrastructure.

I suppose you have also seen the
contributing code page
 - especially about the contribution agreement.

Looking forward to your contributions!