plugin.xml

<?xml version="1.0" encoding="UTF-8"?>
<?eclipse version="3.4"?>
<plugin>
  <extension id="javaFileBuilder" name="Java File Builder" point="org.eclipse.core.resources.builders">
    <builder hasNature="true">
      <run class="com.mycompany.converterhelper.builder.JavaFileBuilder" />
    </builder>
  </extension>
  <extension id="javaFileNature" name="Java File Nature" point="org.eclipse.core.resources.natures">
    <runtime>
      <run class="com.mycompany.converterhelper.builder.JavaFileNature" />
    </runtime>
    <builder id="com.mycompany.converterhelper.javaFileBuilder" />
  </extension>
  <extension point="org.eclipse.ui.commands">
    <category name="Converter Helper" id="com.mycompany.converterhelper.javaFileNature.category" />
    <command name="Toggle My Comp. Converter Notifications" defaultHandler="com.mycompany.converterhelper.builder.AddRemoveJavaFileNatureHandler" categoryId="com.mycompany.converterhelper.javaFileNature.category" id="com.mycompany.converterhelper.addRemoveJavaFileNature" />
  </extension>
  <extension point="org.eclipse.ui.menus">
    <menuContribution locationURI="popup:org.eclipse.jdt.ui.PackageExplorer?before=additions">
      <separator name="com.mycompany.converterhelper.separator" visible="true" />
      <command commandId="com.mycompany.converterhelper.addRemoveJavaFileNature" icon="res/EnableIcon.gif" label="Enable My Comp. Converter Notifications" style="push">
        <visibleWhen checkEnabled="false">
          <with variable="activeMenuSelection">
            <count value="1" />
            <iterate operator="and">
              <adapt type="org.eclipse.core.resources.IResource">
                <and>
                  <not>
                    <test property="org.eclipse.core.resources.projectNature" value="com.mycompany.converterhelper.javaFileNature" />
                  </not>
                  <test property="org.eclipse.core.resources.projectNature" value="org.eclipse.jdt.core.javanature" />
                </and>
              </adapt>
            </iterate>
          </with>
        </visibleWhen>
      </command>
      <command commandId="com.mycompany.converterhelper.addRemoveJavaFileNature" icon="res/DisableIcon.gif" label="Disable My Comp. Converter Notifications" style="push">
        <visibleWhen checkEnabled="false">
          <with variable="activeMenuSelection">
            <count value="1" />
            <iterate operator="and">
              <adapt type="org.eclipse.core.resources.IResource">
                <and>
                  <test property="org.eclipse.core.resources.projectNature" value="com.mycompany.converterhelper.javaFileNature" />
                  <test property="org.eclipse.core.resources.projectNature" value="org.eclipse.jdt.core.javanature" />
                </and>
              </adapt>
            </iterate>
          </with>
        </visibleWhen>
      </command>
    </menuContribution>
  </extension>
  <extension point="org.eclipse.ui.menus">
    <menuContribution locationURI="popup:org.eclipse.ui.navigator.ProjectExplorer#PopupMenu?before=additions">
      <separator name="com.mycompany.converterhelper.separator" visible="true" />
      <command commandId="com.mycompany.converterhelper.addRemoveJavaFileNature" icon="res/EnableIcon.gif" label="Enable My Comp. Converter Notifications" style="push">
        <visibleWhen checkEnabled="false">
          <with variable="activeMenuSelection">
            <count value="1" />
            <iterate operator="and">
              <instanceof value="org.eclipse.core.resources.IProject" />
              <not>
                <test property="org.eclipse.core.resources.projectNature" value="com.mycompany.converterhelper.javaFileNature" />
              </not>
              <test property="org.eclipse.core.resources.projectNature" value="org.eclipse.jdt.core.javanature" />
              <not>
                <test property="org.eclipse.core.resources.name" value="External Plug-in Libraries" />
              </not>
            </iterate>
          </with>
        </visibleWhen>
      </command>
      <command commandId="com.mycompany.converterhelper.addRemoveJavaFileNature" icon="res/DisableIcon.gif" label="Disable My Comp. Converter Notifications" style="push">
        <visibleWhen checkEnabled="false">
          <with variable="activeMenuSelection">
            <count value="1" />
            <iterate operator="and">
              <instanceof value="org.eclipse.core.resources.IProject" />
              <test property="org.eclipse.core.resources.projectNature" value="com.mycompany.converterhelper.javaFileNature" />
            </iterate>
          </with>
        </visibleWhen>
      </command>
    </menuContribution>
  </extension>
  <extension id="converterProblem" name="My Comp. Converter Problem" point="org.eclipse.core.resources.markers">
    <super type="org.eclipse.core.resources.problemmarker" />
    <persistent value="true" />
  </extension>
  <extension id="converterHelper" name="My Comp. Converter Helper" point="org.eclipse.ui.startup" />
  <extension point="org.eclipse.ui.bindings">
    <key commandId="com.mycompany.converterhelper.addRemoveJavaFileNature" schemeId="org.eclipse.ui.defaultAcceleratorConfiguration" sequence="M1+O" />
  </extension>
</plugin>