GWT & ANT Classpath

[sam wootton]

Hi,

Many thanks in advance for any help or advice.

I have a problem with my project structure and classpath. Project and pkg structure is:

[project]
build.xml

[project] [src] [gwt]
MFClient.gwt.xml

[project] [src] [gwt] [client]
MFClient.java

MFClient.gwt.xml

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE module PUBLIC "-//Google Inc.//DTD Google Web Toolkit 2.6.0//EN"
  "http://google-web-toolkit.googlecode.com/svn/tags/2.6.0/distro-source/core/src/gwt-module.dtd">
<module rename-to='gwt.client.MFClient'>

  <inherits name='com.google.gwt.user.User'/>
  <inherits name='com.google.gwt.user.theme.clean.Clean'/>

  <entry-point class='gwt.client.MFClient'/>

  <source path='client'/>

  <add-linker name="xsiframe"/>
</module>

Ant build.xml

<?xml version="1.0" encoding="utf-8" ?>
<!-- CHANGED base dir to . -->
<project name="MFClient" default="build" basedir=".">
    <!-- Arguments to gwtc and devmode targets -->
    <property name="gwt.args" value="" />

    <!-- Configure path to GWT SDK -->
    <property name="gwt.sdk" location="/home/swootton/Downloads/gwt-2.6.0/" />

    <path id="project.class.path">
        <pathelement location="war/WEB-INF/classes"/>
        <pathelement location="${gwt.sdk}/gwt-user.jar"/>
        <fileset dir="${gwt.sdk}" includes="gwt-dev*.jar"/>
        <!-- Add any additional non-server libs (such as JUnit) -->
        <fileset dir="war/WEB-INF/lib" includes="**/*.jar"/>
    </path>

    <target name="libs" description="Copy libs to WEB-INF/lib">
        <mkdir dir="war/WEB-INF/lib" />
        <copy todir="war/WEB-INF/lib" file="${gwt.sdk}/gwt-servlet.jar" />
        <copy todir="war/WEB-INF/lib" file="${gwt.sdk}/gwt-servlet-deps.jar" />
        <!-- Add any additional server libs that need to be copied -->
    </target>

    <target name="javac" depends="libs" description="Compile java source to bytecode">
        <mkdir dir="war/WEB-INF/classes"/>
        <javac srcdir="src" includes="**" encoding="utf-8"
               destdir="war/WEB-INF/classes"
               source="1.5" target="1.5" nowarn="true"
               debug="true" debuglevel="lines,vars,source">
            <classpath refid="project.class.path"/>
            <exclude name="server/"/>
            <exclude name="client/"/>
        </javac>
        <copy todir="war/WEB-INF/classes">
            <fileset dir="src" excludes="**/*.java">
                <exclude name="**/server/**"/>
                <exclude name="**/client/**"/>
            </fileset>
        </copy>
    </target>

    <target name="gwtc" depends="javac" description="GWT compile to JavaScript (production mode)">
        <java failonerror="true" fork="true" classname="com.google.gwt.dev.Compiler">
            <classpath>
                <pathelement location="src"/>
                <path refid="project.class.path"/>
                <pathelement location="${gwt.sdk}/validation-api-1.0.0.GA.jar" />
                <pathelement location="${gwt.sdk}/validation-api-1.0.0.GA-sources.jar" />
            </classpath>
            <!-- add jvmarg -Xss16M or similar if you see a StackOverflowError -->
            <jvmarg value="-Xmx256M"/>
            <arg line="-war"/>
            <arg value="war"/>
            <!-- Additional arguments like -style PRETTY or -logLevel DEBUG -->
            <arg line="${gwt.args}"/>
            <arg value="gwt.client.MFClient"/>
        </java>
    </target>

    <target name="build" depends="gwtc" description="Build this project" />

    <target name="clean" description="Cleans this project">
        <delete dir="war" failonerror="true" />
    </target>

</project>

When I run "ant build" I get the following error

gwtc:
     [java] Loading inherited module 'gwt.client.MFClient'
     [java]    [ERROR] Unable to find 'gwt/client/MFClient.gwt.xml' on your classpath; could be a typo, or maybe you forgot to include a classpath entry for source?

When I move my MFClient.gwt.xml' file to the same package level as my MFClient.java, so:

[project] [src] [gwt] [client]
MFClient.java
MFClient.gwt.xml

It compiles, but I get the following error:

gwtc:
     [java] Compiling module gwt.client.MFClient
     [java]    Finding entry point classes
     [java]       [ERROR] Unable to find type 'gwt.client.MFClient'
     [java]          [ERROR] Hint: Previous compiler errors may have made this type unavailable
     [java]          [ERROR] Hint: Check the inheritance chain from your module; it may not be inheriting a required module or a module may not be adding its source path entries properly

However I do end up with a gwt-unitCache and classes copied to my war directory.

I have tried

<source path='gwt.client'/>
<source path='client'/>

.. and no source path at all, however seem to always have classpath problems, either not finding the java, or not finding my gwt.xml file.

Regards, Sam

[sam wootton]

Resolved by changing "<arg value="gwt.MFClient"/>" in build.xml

<target name="gwtc" depends="javac" description="GWT compile to JavaScript (production mode)">
        <java failonerror="true" fork="true" classname="com.google.gwt.dev.Compiler">
            <classpath>
                <!--Each path element in the classpath is a root against which fully-qualified names (package + class name) are resolved-->
                <!-- location attribute specifies single file or directory relative to project's base directory -->
                <pathelement location="src"/>
                <path refid="project.class.path"/>
                <pathelement location="${gwt.sdk}/validation-api-1.0.0.GA.jar" />
                <pathelement location="${gwt.sdk}/validation-api-1.0.0.GA-sources.jar" />
            </classpath>
            <!-- add jvmarg -Xss16M or similar if you see a StackOverflowError -->
            <jvmarg value="-Xmx256M"/>
            <arg line="-war"/>
            <arg value="war"/>
            <!-- Additional arguments like -style PRETTY or -logLevel DEBUG -->
            <arg line="${gwt.args}"/>
            [b]<arg value="gwt.MFClient"/>[/b]
        </java>
    </target>

And moving MFClient.gwt.xml to

[project] [src] [gwt]

and removing source path in gwt.xml:

<?xml version="1.0" encoding="UTF-8"?>
<!--
  When updating your version of GWT, you should also update this DTD reference,
  so that your app can take advantage of the latest GWT module capabilities.
-->
<!DOCTYPE module PUBLIC "-//Google Inc.//DTD Google Web Toolkit 2.6.0//EN"
  "http://google-web-toolkit.googlecode.com/svn/tags/2.6.0/distro-source/core/src/gwt-module.dtd">
<module rename-to='gwt.client.MFClient'>
  <!-- Inherit the core Web Toolkit stuff.                        -->
  <inherits name='com.google.gwt.user.User'/>

  <!-- Inherit the default GWT style sheet.  You can change       -->
  <!-- the theme of your GWT application by uncommenting          -->
  <!-- any one of the following lines.                            -->
  <inherits name='com.google.gwt.user.theme.clean.Clean'/>
  <!-- <inherits name='com.google.gwt.user.theme.standard.Standard'/> -->
  <!-- <inherits name='com.google.gwt.user.theme.chrome.Chrome'/> -->
  <!-- <inherits name='com.google.gwt.user.theme.dark.Dark'/>     -->

  <!-- Other module inherits                                      -->

  <!-- Specify the app entry point class.                         -->
  <entry-point class='gwt.client.MFClient'/>

  <!-- Specify the paths for translatable code                    -->
  <!--<source path='gwt.client'/>-->
  <!--<source path='shared'/>-->

  <!-- allow Super Dev Mode -->
  <add-linker name="xsiframe"/>
</module>

Regards, Sam

[Maneesh Godbole]

Well done. And for coming back and sharing your solution with others, you just earned yourself a cow!