diff --git a/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/evaluation/QueryService.java b/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/evaluation/QueryService.java
index b49b0c813..341713bfa 100644
--- a/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/evaluation/QueryService.java
+++ b/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/evaluation/QueryService.java
@@ -20,11 +20,9 @@
 import org.eclipse.acceleo.Query;
 import org.eclipse.acceleo.Variable;
 import org.eclipse.acceleo.aql.completion.proposals.QueryServiceCompletionProposal;
-import org.eclipse.acceleo.query.ast.Call;
 import org.eclipse.acceleo.query.parser.AstValidator;
 import org.eclipse.acceleo.query.runtime.ICompletionProposal;
 import org.eclipse.acceleo.query.runtime.IReadOnlyQueryEnvironment;
-import org.eclipse.acceleo.query.runtime.IValidationResult;
 import org.eclipse.acceleo.query.runtime.impl.ValidationServices;
 import org.eclipse.acceleo.query.runtime.namespace.IQualifiedNameLookupEngine;
 import org.eclipse.acceleo.query.validation.type.IType;
@@ -64,7 +62,7 @@ public String getName() {
 	}
 
 	@Override
-	public List<IType> getParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
+	public List<IType> computeParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
 		List<IType> result = new ArrayList<IType>();
 		final AstValidator validator = new AstValidator(new ValidationServices(queryEnvironment));
 		for (Variable var : getOrigin().getParameters()) {
@@ -82,19 +80,7 @@ public int getNumberOfParameters() {
 	}
 
 	@Override
-	public Set<IType> getType(Call call, ValidationServices services, IValidationResult validationResult,
-			IReadOnlyQueryEnvironment queryEnvironment, List<IType> argTypes) {
-		final AstValidator validator = new AstValidator(services);
-
-		final Set<IType> result = validator.getDeclarationTypes(queryEnvironment, validator.validate(
-				Collections.emptyMap(), getOrigin().getType()).getPossibleTypes(getOrigin().getType()
-						.getAst()));
-
-		return result;
-	}
-
-	@Override
-	public Set<IType> getType(IReadOnlyQueryEnvironment queryEnvironment) {
+	public Set<IType> computeType(IReadOnlyQueryEnvironment queryEnvironment) {
 		final AstValidator validator = new AstValidator(new ValidationServices(queryEnvironment));
 
 		final Set<IType> result = validator.getDeclarationTypes(queryEnvironment, validator.validate(
diff --git a/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/evaluation/TemplateService.java b/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/evaluation/TemplateService.java
index 9dd523ab5..c23e1bcda 100644
--- a/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/evaluation/TemplateService.java
+++ b/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/evaluation/TemplateService.java
@@ -64,7 +64,7 @@ public String getName() {
 	}
 
 	@Override
-	public List<IType> getParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
+	public List<IType> computeParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
 		final List<IType> result = new ArrayList<IType>();
 		final AstValidator validator = new AstValidator(new ValidationServices(queryEnvironment));
 		for (Variable var : getOrigin().getParameters()) {
@@ -82,7 +82,7 @@ public int getNumberOfParameters() {
 	}
 
 	@Override
-	public Set<IType> getType(IReadOnlyQueryEnvironment queryEnvironment) {
+	public Set<IType> computeType(IReadOnlyQueryEnvironment queryEnvironment) {
 		Set<IType> result = new LinkedHashSet<IType>();
 		result.add(new ClassType(queryEnvironment, String.class));
 
diff --git a/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/parser/AcceleoAstSerializer.java b/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/parser/AcceleoAstSerializer.java
index 7cf4badd3..03902894a 100644
--- a/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/parser/AcceleoAstSerializer.java
+++ b/plugins/org.eclipse.acceleo.aql/src/org/eclipse/acceleo/aql/parser/AcceleoAstSerializer.java
@@ -39,6 +39,7 @@
 import org.eclipse.acceleo.Template;
 import org.eclipse.acceleo.TextStatement;
 import org.eclipse.acceleo.Variable;
+import org.eclipse.acceleo.query.parser.AstBuilder;
 import org.eclipse.acceleo.query.parser.AstSerializer;
 import org.eclipse.acceleo.util.AcceleoSwitch;
 
@@ -113,7 +114,8 @@ public String serialize(AcceleoASTNode node) {
 
 	@Override
 	public Object caseBinding(Binding binding) {
-		builder.append(binding.getName());
+		final String bindingName = AstBuilder.protectWithUnderscore(binding.getName());
+		builder.append(bindingName);
 		if (binding.getType() != null) {
 			builder.append(" : ");
 			builder.append(querySerializer.serialize(binding.getType().getAst()));
@@ -567,7 +569,8 @@ public Object caseTextStatement(TextStatement textStatement) {
 
 	@Override
 	public Object caseVariable(Variable variable) {
-		builder.append(variable.getName());
+		final String variableName = AstBuilder.protectWithUnderscore(variable.getName());
+		builder.append(variableName);
 		builder.append(SPACE);
 		builder.append(AcceleoParser.COLON);
 		builder.append(SPACE);
diff --git a/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/parser/AstSerializer.java b/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/parser/AstSerializer.java
index 3fae9f80c..5d5b2e6a6 100644
--- a/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/parser/AstSerializer.java
+++ b/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/parser/AstSerializer.java
@@ -147,7 +147,8 @@ private static Map<String, Integer> initOperatorPrecedence() {
 
 	@Override
 	public Object caseBinding(Binding binding) {
-		builder.append(binding.getName());
+		final String bindingName = AstBuilder.protectWithUnderscore(binding.getName());
+		builder.append(bindingName);
 		if (binding.getType() != null) {
 			builder.append(SPACE).append(':').append(SPACE);
 			builder.append(doSwitch(binding.getType()));
@@ -932,7 +933,8 @@ public Object caseEClassifierTypeLiteral(EClassifierTypeLiteral object) {
 
 	@Override
 	public Object caseVariableDeclaration(VariableDeclaration variableDeclaration) {
-		builder.append(variableDeclaration.getName());
+		final String variableName = AstBuilder.protectWithUnderscore(variableDeclaration.getName());
+		builder.append(variableName);
 		if (variableDeclaration.getType() != null) {
 			builder.append(SPACE).append(':').append(SPACE);
 			doSwitch(variableDeclaration.getType());
@@ -942,7 +944,8 @@ public Object caseVariableDeclaration(VariableDeclaration variableDeclaration) {
 
 	@Override
 	public Object caseVarRef(VarRef varRef) {
-		builder.append(varRef.getVariableName());
+		final String variableName = AstBuilder.protectWithUnderscore(varRef.getVariableName());
+		builder.append(variableName);
 		return DUMMY;
 	}
 
diff --git a/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/AbstractService.java b/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/AbstractService.java
index 04adb8952..995acb27e 100644
--- a/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/AbstractService.java
+++ b/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/AbstractService.java
@@ -40,6 +40,22 @@ public abstract class AbstractService<O> implements IService<O> {
 	 */
 	private final O origin;
 
+	/**
+	 * Known {@link IReadOnlyQueryEnvironment} to invalidate cached {@link #returnTypes} and
+	 * {@link #res}.
+	 */
+	private IReadOnlyQueryEnvironment knwonEnvironment;
+
+	/**
+	 * Return {@link IType} cache.
+	 */
+	private Set<IType> returnTypes;
+
+	/**
+	 * Parameters {@link IType} cache.
+	 */
+	private List<IType> res;
+
 	/**
 	 * Constructor with an {@link Object origin}.
 	 * 
@@ -60,6 +76,44 @@ public O getOrigin() {
 		return this.origin;
 	}
 
+	@Override
+	public List<IType> getParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
+		if (knwonEnvironment != queryEnvironment || returnTypes == null) {
+			knwonEnvironment = queryEnvironment;
+			res = computeParameterTypes(queryEnvironment);
+		}
+
+		return res;
+	}
+
+	/**
+	 * Computes the {@link #getParameterTypes(IReadOnlyQueryEnvironment)}.
+	 * 
+	 * @param queryEnvironment
+	 *            the {@link IReadOnlyQueryEnvironment}
+	 * @return the {@link #getParameterTypes(IReadOnlyQueryEnvironment)}
+	 */
+	protected abstract List<IType> computeParameterTypes(IReadOnlyQueryEnvironment queryEnvironment);
+
+	@Override
+	public Set<IType> getType(IReadOnlyQueryEnvironment queryEnvironment) {
+		if (knwonEnvironment != queryEnvironment || returnTypes == null) {
+			knwonEnvironment = queryEnvironment;
+			returnTypes = computeType(queryEnvironment);
+		}
+
+		return returnTypes;
+	}
+
+	/**
+	 * Computes the {@link #getType(IReadOnlyQueryEnvironment)}.
+	 * 
+	 * @param queryEnvironment
+	 *            the {@link IReadOnlyQueryEnvironment}
+	 * @return the {@link #getType(IReadOnlyQueryEnvironment)}
+	 */
+	protected abstract Set<IType> computeType(IReadOnlyQueryEnvironment queryEnvironment);
+
 	/**
 	 * {@inheritDoc}
 	 *
diff --git a/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/EOperationService.java b/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/EOperationService.java
index acdaf5828..b66425a23 100644
--- a/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/EOperationService.java
+++ b/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/EOperationService.java
@@ -111,23 +111,13 @@ private Method lookupMethod(EOperation operation) {
 		return result;
 	}
 
-	/**
-	 * {@inheritDoc}
-	 *
-	 * @see org.eclipse.acceleo.query.runtime.IService#getName()
-	 */
 	@Override
 	public String getName() {
 		return getOrigin().getName();
 	}
 
-	/**
-	 * {@inheritDoc}
-	 *
-	 * @see org.eclipse.acceleo.query.runtime.IService#getParameterTypes(org.eclipse.acceleo.query.runtime.IReadOnlyQueryEnvironment)
-	 */
 	@Override
-	public List<IType> getParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
+	public List<IType> computeParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
 		final List<IType> result = new ArrayList<IType>();
 
 		result.add(new EClassifierType(queryEnvironment, getOrigin().getEContainingClass()));
@@ -143,21 +133,11 @@ public List<IType> getParameterTypes(IReadOnlyQueryEnvironment queryEnvironment)
 		return result;
 	}
 
-	/**
-	 * {@inheritDoc}
-	 *
-	 * @see org.eclipse.acceleo.query.runtime.IService#getNumberOfParameters()
-	 */
 	@Override
 	public int getNumberOfParameters() {
 		return getOrigin().getEParameters().size() + 1;
 	}
 
-	/**
-	 * {@inheritDoc}
-	 *
-	 * @see org.eclipse.acceleo.query.runtime.impl.AbstractService#internalInvoke(java.lang.Object[])
-	 */
 	@Override
 	protected Object internalInvoke(Object[] arguments) throws Exception {
 		final Object result;
@@ -242,18 +222,13 @@ private Object eOperationJavaInvoke(Method eInvokeMethod, final Object receiver,
 		}
 	}
 
-	/**
-	 * {@inheritDoc}
-	 *
-	 * @see org.eclipse.acceleo.query.runtime.IService#getPriority()
-	 */
 	@Override
 	public int getPriority() {
 		return PRIORITY;
 	}
 
 	@Override
-	public Set<IType> getType(IReadOnlyQueryEnvironment queryEnvironment) {
+	public Set<IType> computeType(IReadOnlyQueryEnvironment queryEnvironment) {
 		final Set<IType> result = new LinkedHashSet<IType>();
 
 		final IType eClassifierType = new EClassifierType(queryEnvironment, getOrigin().getEType());
@@ -266,12 +241,6 @@ public Set<IType> getType(IReadOnlyQueryEnvironment queryEnvironment) {
 		return result;
 	}
 
-	/**
-	 * {@inheritDoc}
-	 *
-	 * @see org.eclipse.acceleo.query.runtime.impl.AbstractService#matches(org.eclipse.acceleo.query.runtime.IReadOnlyQueryEnvironment,
-	 *      org.eclipse.acceleo.query.validation.type.IType[])
-	 */
 	@Override
 	public boolean matches(IReadOnlyQueryEnvironment queryEnvironment, IType[] argumentTypes) {
 		final List<Set<IType>> eClassifierTypes = new ArrayList<Set<IType>>(argumentTypes.length);
@@ -335,11 +304,6 @@ public boolean matches(IReadOnlyQueryEnvironment queryEnvironment, IType[] argum
 		return canMatch;
 	}
 
-	/**
-	 * {@inheritDoc}
-	 *
-	 * @see org.eclipse.acceleo.query.runtime.IService#getShortSignature()
-	 */
 	@Override
 	public String getShortSignature() {
 		final List<IType> parameterTypes = getParameterTypes(null);
@@ -348,11 +312,6 @@ public String getShortSignature() {
 		return serviceShortSignature(argumentTypes);
 	}
 
-	/**
-	 * {@inheritDoc}
-	 *
-	 * @see org.eclipse.acceleo.query.runtime.IService#getLongSignature()
-	 */
 	@Override
 	public String getLongSignature() {
 		final String ePkgNsURI;
@@ -375,21 +334,11 @@ public String getLongSignature() {
 		return ePkgNsURI + " " + eCLassName + " " + getShortSignature();
 	}
 
-	/**
-	 * {@inheritDoc}
-	 *
-	 * @see java.lang.Object#equals(java.lang.Object)
-	 */
 	@Override
 	public boolean equals(Object obj) {
 		return obj instanceof EOperationService && ((EOperationService)obj).getOrigin().equals(getOrigin());
 	}
 
-	/**
-	 * {@inheritDoc}
-	 *
-	 * @see java.lang.Object#hashCode()
-	 */
 	@Override
 	public int hashCode() {
 		return getOrigin().hashCode();
diff --git a/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/JavaMethodService.java b/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/JavaMethodService.java
index 92ca2cf02..4ec4cc771 100644
--- a/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/JavaMethodService.java
+++ b/query/plugins/org.eclipse.acceleo.query/src/org/eclipse/acceleo/query/runtime/impl/JavaMethodService.java
@@ -92,14 +92,14 @@ public String getName() {
 	}
 
 	@Override
-	public List<IType> getParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
-		final List<IType> result = new ArrayList<IType>();
+	public List<IType> computeParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
+		final List<IType> res = new ArrayList<IType>();
 
 		for (Class<?> cls : getOrigin().getParameterTypes()) {
-			result.add(getClassType(queryEnvironment, cls));
+			res.add(getClassType(queryEnvironment, cls));
 		}
 
-		return result;
+		return res;
 	}
 
 	/**
@@ -180,15 +180,13 @@ public int getPriority() {
 	}
 
 	@Override
-	public Set<IType> getType(IReadOnlyQueryEnvironment queryEnvironment) {
-		if (knwonEnvironment != queryEnvironment || returnTypes == null) {
-			knwonEnvironment = queryEnvironment;
-			returnTypes = new LinkedHashSet<IType>();
-			Type returnType = getOrigin().getGenericReturnType();
-			returnTypes.addAll(getIType(queryEnvironment, returnType));
-		}
+	public Set<IType> computeType(IReadOnlyQueryEnvironment queryEnvironment) {
+		final Set<IType> res = new LinkedHashSet<IType>();
+
+		Type returnType = getOrigin().getGenericReturnType();
+		res.addAll(getIType(queryEnvironment, returnType));
 
-		return returnTypes;
+		return res;
 	}
 
 	/**
diff --git a/query/tests/org.eclipse.acceleo.query.tests/src/org/eclipse/acceleo/query/tests/runtime/lookup/basic/TestServiceProvider.java b/query/tests/org.eclipse.acceleo.query.tests/src/org/eclipse/acceleo/query/tests/runtime/lookup/basic/TestServiceProvider.java
index f39b91b91..b4050b69e 100644
--- a/query/tests/org.eclipse.acceleo.query.tests/src/org/eclipse/acceleo/query/tests/runtime/lookup/basic/TestServiceProvider.java
+++ b/query/tests/org.eclipse.acceleo.query.tests/src/org/eclipse/acceleo/query/tests/runtime/lookup/basic/TestServiceProvider.java
@@ -14,13 +14,10 @@
 import java.util.List;
 import java.util.Set;
 
-import org.eclipse.acceleo.query.ast.Call;
 import org.eclipse.acceleo.query.runtime.IReadOnlyQueryEnvironment;
 import org.eclipse.acceleo.query.runtime.IService;
 import org.eclipse.acceleo.query.runtime.IServiceProvider;
-import org.eclipse.acceleo.query.runtime.IValidationResult;
 import org.eclipse.acceleo.query.runtime.impl.AbstractService;
-import org.eclipse.acceleo.query.runtime.impl.ValidationServices;
 import org.eclipse.acceleo.query.validation.type.ClassType;
 import org.eclipse.acceleo.query.validation.type.IType;
 
@@ -42,43 +39,23 @@ protected Service1(Object serviceOrigin) {
 			super(serviceOrigin);
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getName()
-		 */
 		@Override
 		public String getName() {
 			return SERVICE_NAME;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getShortSignature()
-		 */
 		@Override
 		public String getShortSignature() {
 			return SERVICE_NAME;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getLongSignature()
-		 */
 		@Override
 		public String getLongSignature() {
 			return SERVICE_NAME;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getParameterTypes(org.eclipse.acceleo.query.runtime.IReadOnlyQueryEnvironment)
-		 */
 		@Override
-		public List<IType> getParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
+		public List<IType> computeParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
 			final List<IType> result = new ArrayList<IType>();
 
 			result.add(new ClassType(queryEnvironment, type1));
@@ -86,50 +63,21 @@ public List<IType> getParameterTypes(IReadOnlyQueryEnvironment queryEnvironment)
 			return result;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getNumberOfParameters()
-		 */
 		@Override
 		public int getNumberOfParameters() {
 			return 1;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getPriority()
-		 */
 		@Override
 		public int getPriority() {
 			return priority1;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getType(org.eclipse.acceleo.query.ast.Call,
-		 *      org.eclipse.acceleo.query.runtime.impl.ValidationServices,
-		 *      org.eclipse.acceleo.query.runtime.IValidationResult,
-		 *      org.eclipse.acceleo.query.runtime.IReadOnlyQueryEnvironment, java.util.List)
-		 */
-		@Override
-		public Set<IType> getType(Call call, ValidationServices services, IValidationResult validationResult,
-				IReadOnlyQueryEnvironment queryEnvironment, List<IType> argTypes) {
-			return null;
-		}
-
 		@Override
-		public Set<IType> getType(IReadOnlyQueryEnvironment queryEnvironment) {
+		public Set<IType> computeType(IReadOnlyQueryEnvironment queryEnvironment) {
 			return null;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.impl.AbstractService#internalInvoke(java.lang.Object[])
-		 */
 		@Override
 		protected Object internalInvoke(Object[] arguments) throws Exception {
 			return null;
@@ -146,43 +94,23 @@ protected Service2(Object serviceOrigin) {
 			super(serviceOrigin);
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getName()
-		 */
 		@Override
 		public String getName() {
 			return SERVICE_NAME;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getShortSignature()
-		 */
 		@Override
 		public String getShortSignature() {
 			return SERVICE_NAME;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getLongSignature()
-		 */
 		@Override
 		public String getLongSignature() {
 			return SERVICE_NAME;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getParameterTypes(org.eclipse.acceleo.query.runtime.IReadOnlyQueryEnvironment)
-		 */
 		@Override
-		public List<IType> getParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
+		public List<IType> computeParameterTypes(IReadOnlyQueryEnvironment queryEnvironment) {
 			final List<IType> result = new ArrayList<IType>();
 
 			result.add(new ClassType(queryEnvironment, type2));
@@ -190,50 +118,21 @@ public List<IType> getParameterTypes(IReadOnlyQueryEnvironment queryEnvironment)
 			return result;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getNumberOfParameters()
-		 */
 		@Override
 		public int getNumberOfParameters() {
 			return 1;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getPriority()
-		 */
 		@Override
 		public int getPriority() {
 			return priority2;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.IService#getType(org.eclipse.acceleo.query.ast.Call,
-		 *      org.eclipse.acceleo.query.runtime.impl.ValidationServices,
-		 *      org.eclipse.acceleo.query.runtime.IValidationResult,
-		 *      org.eclipse.acceleo.query.runtime.IReadOnlyQueryEnvironment, java.util.List)
-		 */
-		@Override
-		public Set<IType> getType(Call call, ValidationServices services, IValidationResult validationResult,
-				IReadOnlyQueryEnvironment queryEnvironment, List<IType> argTypes) {
-			return null;
-		}
-
 		@Override
-		public Set<IType> getType(IReadOnlyQueryEnvironment queryEnvironment) {
+		public Set<IType> computeType(IReadOnlyQueryEnvironment queryEnvironment) {
 			return null;
 		}
 
-		/**
-		 * {@inheritDoc}
-		 *
-		 * @see org.eclipse.acceleo.query.runtime.impl.AbstractService#internalInvoke(java.lang.Object[])
-		 */
 		@Override
 		protected Object internalInvoke(Object[] arguments) throws Exception {
 			return null;