diff --git a/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLBehaviorUnitOutlineFilter.java b/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLBehaviorUnitOutlineFilter.java
index 01c46445ba..b22b216225 100644
--- a/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLBehaviorUnitOutlineFilter.java
+++ b/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLBehaviorUnitOutlineFilter.java
@@ -21,10 +21,9 @@
 
 package io.sarl.lang.ui.outline;
 
-import static io.sarl.lang.sarl.SarlPackage.Literals.SARL_BEHAVIOR_UNIT;
+import static io.sarl.lang.ui.outline.SARLOutlineNodeComparator.isBehaviorUnit;
 
 import com.google.inject.Inject;
-import org.eclipse.emf.ecore.EClass;
 import org.eclipse.jface.action.Action;
 import org.eclipse.xtext.ui.IImageHelper.IImageDescriptorHelper;
 import org.eclipse.xtext.ui.editor.outline.IOutlineNode;
@@ -52,16 +51,8 @@ public class SARLBehaviorUnitOutlineFilter extends AbstractFilterOutlineContribu
 	 */
 	public static final String ICON_BASENAME = "hide_behavior_units.png"; //$NON-NLS-1$
 
-	@Inject private IImageDescriptorHelper imageHelper;
-
-	/** Replies if the given type is a behavior unit.
-	 *
-	 * @param type the type to test.
-	 * @return <code>true</code> if the given type is for a behavior unit; <code>false</code> otherwise.
-	 */
-	protected static boolean isBehaviorUnit(EClass type) {
-		return type == SARL_BEHAVIOR_UNIT;
-	}
+	@Inject
+	private IImageDescriptorHelper imageHelper;
 
 	@Override
 	protected boolean apply(IOutlineNode node) {
diff --git a/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLFieldOutlineFilter.java b/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLFieldOutlineFilter.java
index 2372bada7e..19c321583a 100644
--- a/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLFieldOutlineFilter.java
+++ b/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLFieldOutlineFilter.java
@@ -21,10 +21,9 @@
 
 package io.sarl.lang.ui.outline;
 
-import static org.eclipse.xtend.core.xtend.XtendPackage.Literals.XTEND_FIELD;
+import static io.sarl.lang.ui.outline.SARLOutlineNodeComparator.isField;
 
 import com.google.inject.Inject;
-import org.eclipse.emf.ecore.EClass;
 import org.eclipse.jface.action.Action;
 import org.eclipse.xtext.ui.IImageHelper.IImageDescriptorHelper;
 import org.eclipse.xtext.ui.editor.outline.IOutlineNode;
@@ -55,15 +54,6 @@ public class SARLFieldOutlineFilter extends AbstractFilterOutlineContribution {
 	@Inject
 	private IImageDescriptorHelper imageHelper;
 
-	/** Replies if the given type is for a SARL field.
-	 *
-	 * @param type the type to test.
-	 * @return <code>true</code> if the given type is for SARL fields, <code>false</code> otherwise.
-	 */
-	protected static boolean isField(EClass type) {
-		return type == XTEND_FIELD;
-	}
-
 	@Override
 	protected boolean apply(IOutlineNode node) {
 		if (node instanceof EObjectNode) {
diff --git a/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLOperationOutlineFilter.java b/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLOperationOutlineFilter.java
index 239836b4eb..3f617a0cf9 100644
--- a/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLOperationOutlineFilter.java
+++ b/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLOperationOutlineFilter.java
@@ -21,12 +21,9 @@
 
 package io.sarl.lang.ui.outline;
 
-import static io.sarl.lang.sarl.SarlPackage.Literals.SARL_ACTION;
-import static org.eclipse.xtend.core.xtend.XtendPackage.Literals.XTEND_CONSTRUCTOR;
-import static org.eclipse.xtend.core.xtend.XtendPackage.Literals.XTEND_FUNCTION;
+import static io.sarl.lang.ui.outline.SARLOutlineNodeComparator.isAction;
 
 import com.google.inject.Inject;
-import org.eclipse.emf.ecore.EClass;
 import org.eclipse.jface.action.Action;
 import org.eclipse.xtext.ui.IImageHelper.IImageDescriptorHelper;
 import org.eclipse.xtext.ui.editor.outline.IOutlineNode;
@@ -57,24 +54,13 @@ public class SARLOperationOutlineFilter extends AbstractFilterOutlineContributio
 	@Inject
 	private IImageDescriptorHelper imageHelper;
 
-	/** Replies if the given type is for a SARL operation.
-	 *
-	 * @param type the type to test.
-	 * @return <code>true</code> if the given type is for a SARL operation; <code>false</code> otherwise.
-	 */
-	protected static boolean isOperation(EClass type) {
-		return type == SARL_ACTION
-				|| type == XTEND_FUNCTION
-				|| type == XTEND_CONSTRUCTOR;
-	}
-
 	@Override
 	protected boolean apply(IOutlineNode node) {
 		if (node instanceof EObjectNode) {
-			return !isOperation(((EObjectNode) node).getEClass());
+			return !isAction(((EObjectNode) node).getEClass());
 		}
 		if (node instanceof EStructuralFeatureNode) {
-			return !isOperation(((EStructuralFeatureNode) node).getEStructuralFeature().eClass());
+			return !isAction(((EStructuralFeatureNode) node).getEStructuralFeature().eClass());
 		}
 		return true;
 	}
diff --git a/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLOutlineNodeComparator.java b/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLOutlineNodeComparator.java
index f8dc69c671..cb9dbf42a2 100644
--- a/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLOutlineNodeComparator.java
+++ b/main/coreplugins/io.sarl.lang.ui/src/io/sarl/lang/ui/outline/SARLOutlineNodeComparator.java
@@ -28,6 +28,9 @@
 import static org.eclipse.xtend.core.xtend.XtendPackage.Literals.XTEND_FIELD;
 import static org.eclipse.xtend.core.xtend.XtendPackage.Literals.XTEND_FILE__PACKAGE;
 import static org.eclipse.xtend.core.xtend.XtendPackage.Literals.XTEND_FUNCTION;
+import static org.eclipse.xtext.common.types.TypesPackage.Literals.JVM_CONSTRUCTOR;
+import static org.eclipse.xtext.common.types.TypesPackage.Literals.JVM_FIELD;
+import static org.eclipse.xtext.common.types.TypesPackage.Literals.JVM_OPERATION;
 import static org.eclipse.xtext.xtype.XtypePackage.Literals.XIMPORT_SECTION;
 
 import org.eclipse.emf.ecore.EClass;
@@ -83,6 +86,56 @@ public SARLOutlineNodeComparator() {
 		//
 	}
 
+	/** Replies if the given type corresponds to a field.
+	 *
+	 * @param type the type.
+	 * @return {@code true} if the type corresponds to a SARL, Xtend or JVM field.
+	 * @since 0.9
+	 */
+	public static boolean isField(EClass type) {
+		return XTEND_FIELD.isSuperTypeOf(type) || JVM_FIELD.isSuperTypeOf(type);
+	}
+
+	/** Replies if the given type corresponds to an action.
+	 *
+	 * @param type the type.
+	 * @return {@code true} if the type corresponds to a SARL, Xtend or JVM action/method/operation.
+	 * @since 0.9
+	 */
+	public static boolean isAction(EClass type) {
+		return XTEND_FUNCTION.isSuperTypeOf(type) || JVM_OPERATION.isSuperTypeOf(type);
+	}
+
+	/** Replies if the given type corresponds to a constructor.
+	 *
+	 * @param type the type.
+	 * @return {@code true} if the type corresponds to a SARL, Xtend or JVM constructor.
+	 * @since 0.9
+	 */
+	public static boolean isConstructor(EClass type) {
+		return XTEND_CONSTRUCTOR.isSuperTypeOf(type) || JVM_CONSTRUCTOR.isSuperTypeOf(type);
+	}
+
+	/** Replies if the given type corresponds to a behavior unit.
+	 *
+	 * @param type the type.
+	 * @return {@code true} if the type corresponds to a SARL behavior unit.
+	 * @since 0.9
+	 */
+	public static boolean isBehaviorUnit(EClass type) {
+		return SARL_BEHAVIOR_UNIT.isSuperTypeOf(type);
+	}
+
+	/** Replies if the given type corresponds to a capacity use.
+	 *
+	 * @param type the type.
+	 * @return {@code true} if the type corresponds to a SARL capacity use.
+	 * @since 0.9
+	 */
+	public static boolean isCapacityUses(EClass type) {
+		return SARL_CAPACITY_USES.isSuperTypeOf(type);
+	}
+
 	@SuppressWarnings({"checkstyle:npathcomplexity", "checkstyle:returncount",
 			"checkstyle:cyclomaticcomplexity"})
 	@Override
@@ -108,34 +161,31 @@ public int getCategory(IOutlineNode node) {
 				}
 				return INNER_TYPE_PRIORITY;
 			}
-			if (SARL_CAPACITY_USES.isSuperTypeOf(objectNodeType)) {
+			if (isCapacityUses(objectNodeType)) {
 				return CAPACITY_USE_PRIORITY;
 			}
 			if (SARL_REQUIRED_CAPACITY.isSuperTypeOf(objectNodeType)) {
 				return CAPACITY_REQUIREMENT_PRIORITY;
 			}
-			if (XTEND_FIELD.isSuperTypeOf(objectNodeType)) {
+			if (isField(objectNodeType)) {
 				if (isStatic(objectNode)) {
 					return STATIC_FIELD_PRIORITY;
 				}
 				return FIELD_PRIORITY;
 			}
-			if (XTEND_FUNCTION.isSuperTypeOf(objectNodeType)) {
+			if (isAction(objectNodeType)) {
 				if (isStatic(objectNode)) {
 					return STATIC_METHOD_PRIORITY;
 				}
 				return METHOD_PRIORITY;
 			}
-			if (XTEND_CONSTRUCTOR.isSuperTypeOf(objectNodeType)) {
+			if (isConstructor(objectNodeType)) {
 				if (isStatic(objectNode)) {
 					return STATIC_CONSTRUCTOR;
 				}
 				return CONSTRUCTOR_PRIORITY;
 			}
-			if (TypesPackage.Literals.JVM_CONSTRUCTOR.isSuperTypeOf(objectNodeType)) {
-				return CONSTRUCTOR_PRIORITY;
-			}
-			if (SARL_BEHAVIOR_UNIT.isSuperTypeOf(objectNodeType)) {
+			if (isBehaviorUnit(objectNodeType)) {
 				return BEHAVIOR_UNIT_PRIORITY;
 			}
 		}