package org.xtext.example.mydsl.ui;

import java.util.Map;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResourceDelta;
import org.eclipse.core.resources.IResourceDeltaVisitor;
import org.eclipse.core.resources.IncrementalProjectBuilder;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IProgressMonitor;

public class DummyBuilder extends IncrementalProjectBuilder {

    @Override
    protected IProject[] build(int kind, Map<String, String> args, IProgressMonitor monitor) throws CoreException {
        IResourceDelta delta = getDelta(getProject());
        if (delta != null) {
            delta.accept(new IResourceDeltaVisitor() {
                
                @Override
                public boolean visit(IResourceDelta delta) throws CoreException {
                    if (delta.getKind() == IResourceDelta.ADDED || delta.getKind() == IResourceDelta.CHANGED) {
                        if (delta.getResource() instanceof IFile) {
                            System.out.println(delta);
                            // TODO file extensiion check
                            if (delta.getResource().getFullPath().toString().contains("/src-gen")) {
                                delta.getResource().touch(null);
                            }
                        }
                    }
                    return true;
                }
            });
        }
        return null;
    }

}
mydsl.ui/plugin.xml
 <extension
       id="DummyBuilder" name="DummyBuilder"
       point="org.eclipse.core.resources.builders">
       


in .project of model project
    <builder >
        <run
           class="org.xtext.example.mydsl.ui.DummyBuilder">
        </run>
    </builder>
 </extension>

        <buildCommand>
            <name>org.xtext.example.mydsl.ui.DummyBuilder</name>
            <arguments>
            </arguments>
        </buildCommand>