JamChallenge-html org.eclipse.jdt.core.javabuilder com.gwtplugins.gwt.eclipse.core.gwtProjectValidator org.eclipse.wst.common.project.facet.core.builder org.eclipse.wst.validation.validationbuilder com.gwtplugins.gdt.eclipse.core.webAppProjectValidator org.eclipse.jdt.core.javanature com.gwtplugins.gwt.eclipse.core.gwtNature org.eclipse.wst.common.project.facet.core.nature org.eclipse.wst.common.modulecore.ModuleCoreNature org.eclipse.jem.workbench.JavaEMFNature