[news.eclipse.technology.m2e] Problem with m2eclipse Ecore Pom model

[Snjezana Peco <snjeza.peco@xxxxxxxxx>]

I have tried to update pom.xml using m2eclipse Ecore Pom model 
(pre-maven-3 branch).
I have started with the following file:

<project xmlns="http://maven.apache.org/POM/4.0.0"; 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 
http://maven.apache.org/maven-v4_0_0.xsd";>
	<modelVersion>4.0.0</modelVersion>
	<groupId>test</groupId>
	<artifactId>test</artifactId>
	<packaging>war</packaging>
	<name>Test</name>
	<version>0.0.1-SNAPSHOT</version>
</project>

and wanted to get the following file:

<project xmlns="http://maven.apache.org/POM/4.0.0"; 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 
http://maven.apache.org/maven-v4_0_0.xsd";>

	<modelVersion>4.0.0</modelVersion>
	<groupId>test</groupId>
	<artifactId>test</artifactId>
	<packaging>war</packaging>
	<name>Test</name>
	<version>0.0.1-SNAPSHOT</version>

	<build>
		<sourceDirectory>src</sourceDirectory>
		<outputDirectory>bin</outputDirectory>
		<resources>
			<resource>
				<directory>/src</directory>
				<excludes>
					<exclude>**/*.java</exclude>
				</excludes>
			</resource>
		</resources>
		<plugins>
			<plugin>
				artifactId>maven-war-plugin</artifactId>
				<configuration>
				</configuration>
			</plugin>
		</plugins>
	</build>
</project>

The following code creates the correct file, but the file can't be 
removed (Eclipse returns "The xxx/pom.xml file has unsaved changes"):

		IFile pom = project.getFile(IMavenConstants.POM_FILE_NAME);
		MavenModelManager modelManager = 
MavenPlugin.getDefault().getMavenModelManager();
        	PomResourceImpl pomResource = modelManager.loadResource(pom);
        	Model projectDocument = (Model)pomResource.getContents().get(0);
        	Build build = projectDocument.getBuild();
		if (build == null) {
			build = PomFactory.eINSTANCE.createBuild();
		}
		String outputDirectory = javaProject.getOutputLocation().toString();
		build.setOutputDirectory(outputDirectory);
		IClasspathEntry[] entries = javaProject.getRawClasspath();
		String sourceDirectory = null;
		for (int i = 0; i < entries.length; i++) {
			if (entries[i].getEntryKind() == IClasspathEntry.CPE_SOURCE) {
				sourceDirectory = entries[i].getPath().toString();
				build.setSourceDirectory(sourceDirectory);
			}
		}
		EList<Plugin> plugins = build.getPlugins();
		Plugin plugin = PomFactory.eINSTANCE.createPlugin();
		plugin.setGroupId("org.apache.maven.plugins");
		plugin.setArtifactId("maven-war-plugin");
		Configuration configuration = PomFactory.eINSTANCE.createConfiguration();
		plugin.setConfiguration(configuration);
		plugins.add(plugin);
		EList<Resource> resources = build.getResources();
		Resource resource = PomFactory.eINSTANCE.createResource();
		if (sourceDirectory != null) {
			resource.setDirectory(sourceDirectory);
		}
		EList<String> excludes = resource.getExcludes();
		excludes.add("**/*.java");
		resources.add(resource);
		
		projectDocument.setBuild(build);
		try {
			pomResource.save(null);
		} catch (IOException e) {
			throw new Exception(...);
		}
		pomResource.unload();

I suppose pomResource.unload is obliged because it releases the WTP's 
DOMModel (SSESyncResource.doUnload()).
SSESyncResource.doUnload() releases DOMModel, but doesn't release EMF 
resources.
In my opinion, this method needs to be as follows:
  @Override
  protected void doUnload() {
    super.doUnload();  // added to release EMF resources
    domModel.releaseFromEdit();
  }

In this case all the resources are released, the file can be removed, 
but the file isn't created correctly because of a problem in the 
synchronization between WTP DOMModel and EMF Ecore Model.
The created file doesn't contain the "plugins" and "resources" elements.

I believe this issue is the cause of a lot of issues in m2eclipse 
(especially in the Maven Pom Editor)

A workaround for me is to use Maven Pom model 
(org.apache.maven.model.Model).

Snjeza