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Compiling an eclipse GWT project from the command line, without eclipse: compile error

We got a GWT project in Eclipse, that otherwise works.
Now I want to have a script that runs on the server, which pulls the latest version from source control and compiles it on the server and deploys it.
This will save us a lot of manual work and allow us to deploy new version when on a connection with limited bandwidth (since we won't have to upload the application to the server).
After pulling the latest version of the source code, the script tries to compile the code using the following command:
java -cp "/path/eclipse/plugins/com.google.gwt.eclipse.sdkbundle_2.5.0.v201211121240-rel-r42/gwt-2.5.0/*:/path/company/projects/pull-compile-deploy/X/X/src:/path/company/projects/pull-compile-deploy/X/X/war/WEB-INF/lib/*" com.google.gwt.dev.Compiler nl.company.projects.X
Compiling module nl.company.projects.X
Finding entry point classes
[ERROR] Unable to find type 'nl.company.projects.X.client.XMain'
[ERROR] Hint: Previous compiler errors may have made this type unavailable
[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
All source code is in /path/company/projects/pull-compile-deploy/X/X/src and all used .jars (except for the GWT stuff) are in /path/company/projects/pull-compile-deploy/X/X/war/WEB-INF/lib/. Obviously something goes wrong.
Questions: The file /path/company/projects/pull-compile-deploy/X/X/src/nl/company/projects/X/client/XMain.java does exist and should imho be in the classpath?!
Anyone Any idea what might go wrong here?
Is it maybe possible to see in some log exactly the commands that eclipse executes for compilation? I looked at the build.xml that eclipse can export, but it seems that does not contain a target to compile for production.
something else: apperantly GWT expects the X.gwt.xml to be at /path/company/projects/pull-compile-deploy/X/X/src/nl/company/project/X.gwt.xml, whereas eclipse put it in /path/company/projects/pull-compile-deploy/X/X/src/nl/company/project/X/X.gwt.xml (i.e. nested one directory deeper), I fixed this by creating a symbolic link.
Further Edit:
Since one answer focused on how I invoked the compilation tools, I have rewritten that in Ant, see below.
The problem remains of course.
<!-- Compile the source using javac. -->
<target name="compile" depends="init">
<javac srcdir="src/" destdir="bin/">
<classpath refid="project.classpath"/>
</javac>
</target>
<!-- Use the GWT-compiler. -->
<target name="gwt-compile" depends="compile">
<java failonerror="true" fork="true" classname="com.google.gwt.dev.Compiler">
<classpath>
<path refid="project.classpath"/>
<pathelement location="src/"/>
<pathelement location="bin/"/>
</classpath>
<jvmarg value="-Xmx512M"/>
<arg value="${module.name}"/>
</java>
</target>
Anything wrong with the above Ant-script?
module.name = nl.company.projects.X and the path with refid="project.classpath" contains all used libraries aswell as the GWT libraries (gwt-user.jar, gwt-dev.jar and validation-api-1.0.0.GA(-source).jar).
The XMain class inherits nothing (other than from Object) and only implements EntryPoint (which is included in the gwt-user.jar). So I do not think the problem is related to the second hint that the compiler gives.
Any ideas?

GWT requires you to javac your classes, it needs both the *.java and the *.class files.
This has not always been the case, and should change back in the future (see https://code.google.com/p/google-web-toolkit/issues/detail?id=7602 for instance), but for now that's the state of affair: you need to javac before you can com.google.gwt.dev.Compiler.
javac -cp "/path/eclipse/plugins/com.google.gwt.eclipse.sdkbundle_2.5.0.v201211121240-rel-r42/gwt-2.5.0/*:/path/company/projects/pull-compile-deploy/X/X/war/WEB-INF/lib/*" -sourcepath /path/company/projects/pull-compile-deploy/X/X/src /path/company/projects/pull-compile-deploy/X/X/src/nl/company/projects/X.java -d /path/company/projects/pull-compile-deploy/X/X/bin
java -cp "/path/eclipse/plugins/com.google.gwt.eclipse.sdkbundle_2.5.0.v201211121240-rel-r42/gwt-2.5.0/*:/path/company/projects/pull-compile-deploy/X/X/src:/path/company/projects/pull-compile-deploy/X/X/bin:/path/company/projects/pull-compile-deploy/X/X/war/WEB-INF/lib/*" com.google.gwt.dev.Compiler nl.company.projects.X
(please double-check the above commands before use)
EDIT: (in response to your "question" re. the X.gwt.xml): GWT expects the X.gwt.xml at nl/company/projects/X.gwt.xml because that's what you told it to use: module.name = nl.company.projects.x. If the file is at nl/company/projects/X/X.gt.xml then use nl.company.projects.X.X as the module name. Using a symbolic link here is likely to be the problem: the source path for the module (search for <source at https://developers.google.com/web-toolkit/doc/latest/DevGuideOrganizingProjects#DevGuideModuleXml) will then be nl/company/projects/client and thus won't include nl/company/projects/X/client where your XMain class lives; it's this unavailable to the GWT compiler.
That said, I totally agree with SSR: use a decent build tool: Ant, Maven, Gradle, Make, whatever, it'll make your life so much easier. A build tool that manages dependencies (Ant+Ivy, Maven, Gradle) is even better IMO.

Why would you put yourself through such non-standard build exercise like this.
If it is non-academic project then USE maven. If you find maven difficult then use ant.
Examples for both type are provided by GWT team - http://code.google.com/p/google-web-toolkit/source/browse/#svn%2Ftrunk%2Fsamples.
Note - maven has plugins to do most of the stuff you are trying in standardized way.

XML schema method naming inconsistency

I am hoping someone has experienced this issue and can maybe shed some light.
I have an xml schema and an ant build file. The output .java files differ when I run ant on Windows versus Mac, even if I am using the same jaxb-xjc.jar to do the xml-compiling. The Windows side is naming the "getter" methods for attributes as "getX". The Mac side wants to name them "isX". Anyone experience anything like this before and/or have a solution? This is consistent between Windows Vista & 7 doing this the one way and Mac OSX 10.6 & 10.7 (untested on Mac OSX 10.8) doing it the other.
----edit----
I'll attach some of the code from the ant build.xml file.
Telling it what the xjc is.
<taskdef name="xjc" classname="com.sun.tools.xjc.XJCTask">
<classpath refid="classpath"/>
</taskdef>
Here is the 'actual' compiling:
Compiling the automaton schema
<echo>Compiling old automaton schema</echo>
<xjc schema="${oldxml-schema}" destdir="${src.dir}" package="${oldxml.package}">
<produces dir="${oldxml-gen.dir}" includes="**/*.java"/>
</xjc>
<echo>Compiling the plugin schema</echo>
<mkdir dir="${plugin-gen.dir}" />
<xjc schema="${plugin-schema}" destdir="${src.dir}" package="${plugin.package}">
<produces dir="${plugin-gen.dir}" includes="**/*.java"/>
</xjc>
<echo>Compiling the pluginDesumaSide schema</echo>
<mkdir dir="${pluginDesumaSide-gen.dir}" />
<xjc schema="${pluginDesumaSide-schema}" destdir="${src.dir}" package="${pluginDesumaSide.package}">
<produces dir="${pluginDesumaSide-gen.dir}" includes="**/*.java"/>
</xjc>
</target>
All targets (by that I mean anything mentioned like ${}) are defined and every links and compiles right except for Mac naming the 'getter' methods as 'is' methods for variables. They are boolean attributes that do have defaults if non-specified.

From the responses I got I was able to google for a solution. Apparently this naming inconsistency and another (a getter returning a primitive but the setter only accepting objects) was apparent by chance for older xml-compilers due to some inconsistency in the specification.
This was fixed by going to http://jaxb.java.net/ and getting a new jaxb-impl.jar & jaxb-xjc.jar. I downloaded and ran the jaxb.jar file download and it created the needed jars.

Why is my ANTLR grammar file for Java not compiling?

I have been given an ANTLR grammar for a subset of the Java compiler known as the static Java compiler. I am trying to extend the grammar to include more of Java's features, for instance, I just added the grammar for For Loops.
Using Eclipse and an ANTLR plugin, I then did 'Compile ANTLR grammar'. Instead of compiling it produced two errors on the first bit of code:
grammar ExtendedStaticJava;
options { backtrack=true; memoize=true; }
#header
{
package sjc.parser.extended;
import java.math.BigInteger;
/**
* Extended StaticJava parser.
* #author <myname>
*/
}
// the rest of the grammar has been excluded.
The first error is on line 1: 'Unexpected Token: grammar'
The second error is on line 5: 'Unexpected char: #'
Why does it not recognize this basic ANTLR syntax? My first thought was that I was missing something in the classpath, but I went to the project's properties and made sure that the following JARs were included under Libraries:
antlr-2.7.7.jar
stringtemplate-3.2.1.jar
antlr.jar
antlr-runtime-3.0.1.jar
Any ideas or suggestions?

antlr-2.7.7.jar is wrong: your grammar is in ANTLR v3+ syntax. Remove all:
antlr-2.7.7.jar
stringtemplate-3.2.1.jar
antlr.jar
antlr-runtime-3.0.1.jar
from your project/classpath and only stick this ANTLR v3 JAR in it (which contains everything you need: runtime, stringtemplate, the works!).
Good luck!
EDIT
Personally, I do my IDE integration with an Ant build script. I generate a lexer and parser like this:
<target name="generate.parser" depends="init" description="Generates the lexer, parser and tree-walker from the grammar files.">
<echo>Generating the lexer and parser...</echo>
<java classname="org.antlr.Tool" fork="true" failonerror="true">
<arg value="-fo" />
<arg value="${main.src.dir}/${parser.package}" />
<arg value="${parser.grammar.file}" />
<classpath refid="classpath" />
</java>
<!-- snip -->
</target>
and the classpath refid looks like:
<path id="classpath">
<!-- snip -->
<fileset dir="lib">
<include name="*.jar" />
</fileset>
</path>
and the lib/ directory contains the ANTLR v3 JAR (no other ANTLR JARs! (sorry for hammering on that :)))

You have probably installed the AntlrEclipse plugin. This indeed uses Antlr 2.7.something. There is however a plugin available that works with v3, Antlr IDE. This plugin is a little bit more advanced as it allows you to configure the Antlr version (3+) and can show a railroad view and has an interpreter.
Note If you are using Eclipse Juno, you will need to install the DLTK from the Indigo repositorties, as 4.0.0 is to new for the antlr plugin

I had this issue as well.
At some point during my attempts to get antlr running I had added some version of the jar file to my classpath windows environment variable. I removed this entry, and it resolved my issue.

Troubleshooting "failed to create task or type foreach" when using <foreach>

I'm trying to use the foreach loop in an Ant script but I get the message: Problem: failed to create task or type foreach Cause: The name is undefined.
I don't understand why this doesn't work. It is not a 3rd party library. It is a standard task that would be part of the latest version of Ant (1.8).
<target name="parse">
<echo message="The first five letters of the alphabet are:"/>
<foreach param="instance" list="a,b,c,d,e">
</foreach>
</target>

It is a standard task that would be
part of the latest version of Ant
(1.8).
No, it's not. At least I can't find it in the list of core and optional tasks in the ant manual.
It seems to be part of the ant-contrib project and thus needs to be installed separately.

I had the same issue under eclipse with various versions of ant.
Add this into your code WITHOUT adding parameters under eclipse (do not specify any classpath) :
<taskdef resource="net/sf/antcontrib/antcontrib.properties" classpath="/path/to/ant-contrib/ant-contrib-1.0b3.jar"/>

have you ever considered <script>? in this tag you can use some famous script language like javascript and python. they can also interact with the Project, Task... Object of Ant, which means you can set/get the properties and even excute another task. look at this example which comes from the book "java development with ant"
<project name="script_example" default="test-random">
<description>
Use a script task to generate a random number, then
print it
</description>
<target name="random">
<script language="javascript"><![CDATA[
//NB: an unqualified Math is the JavaScript object
var r=java.lang.Math.random();
var num = Math.round(r*10);
project.setNewProperty("random", num);
self.log("Generated random number " + num, project.MSG_DEBUG);
]]>
</script>
</target>
<target name="test-random" depends="random">
<echo>Random number is ${random}</echo>
</target>
</project>

I can't find the foreach task in the Ant 1.8 manual - where is it? I only know the task from ant-contrib, and it requires to specify the 'target' attribute: http://ant-contrib.sourceforge.net/tasks/tasks/foreach.html

You haven't defined a target to call:
<foreach param="instance" list="a,b,c,d,e" target="processListItem" />
alternatively:
<for param="instance" list="a,b,c,d,e" >
<sequential>
<!-- Do Something with #{instance} -->
</sequential>
</for>

When using ANT, how can I define a task only if I have some specific java version?

I have the problem that an specific step in Ant can only be executed when we have Java 1.5 installed in the build computer. The task definition uses uses a jar file that was compiled using 1.5, so running with a 1.4 virtual machine will throw an IncompatibleClassVersion exception.
I have to find a solution meanwhile to have this task working for this specific project that requires 1.4, but a question came to me. How can I avoid defining this task and executing this optional step if I don't have a specific java version?
I could use the "if" or "unless" tags on the target tag, but those only check if a property is set or not. I also would like to have a solution that doesn't require extra libraries, but I don't know if the build-in functionality in standard is enough to perform such a task.

The Java version is exposed via the ant.java.version property. Use a condition to set a property and execute the task only if it is true.
<?xml version="1.0" encoding="UTF-8"?>
<project name="project" default="default">
<target name="default" depends="javaCheck" if="isJava6">
<echo message="Hello, World!" />
</target>
<target name="javaCheck">
<echo message="ant.java.version=${ant.java.version}" />
<condition property="isJava6">
<equals arg1="${ant.java.version}" arg2="1.6" />
</condition>
</target>
</project>

The property to check in the buildfile is ${ant.java.version}.
You could use the <condition> element to make a task conditional when a property equals a certain value:
<condition property="legal-java">
<matches pattern="1.[56].*" string="${ant.java.version}"/>
</condition>