diff --git a/ExpMath/nb-configuration.xml b/ExpMath/nb-configuration.xml
new file mode 100644
index 0000000..98cd079
--- /dev/null
+++ b/ExpMath/nb-configuration.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project-shared-configuration>
+    <!--
+This file contains additional configuration written by modules in the NetBeans IDE.
+The configuration is intended to be shared among all the users of project and
+therefore it is assumed to be part of version control checkout.
+Without this configuration present, some functionality in the IDE may be limited or fail altogether.
+-->
+    <properties xmlns="http://www.netbeans.org/ns/maven-properties-data/1">
+        <!--
+Properties that influence various parts of the IDE, especially code formatting and the like. 
+You can copy and paste the single properties, into the pom.xml file and the IDE will pick them up.
+That way multiple projects can share the same settings (useful for formatting rules for example).
+Any value defined here will override the pom.xml file value but is only applicable to the current project.
+-->
+        <netbeans.hint.license>gpl30</netbeans.hint.license>
+    </properties>
+</project-shared-configuration>
diff --git a/ExpMath/src/main/java/net/cofares/model/Add.java b/ExpMath/src/main/java/net/cofares/model/Add.java
index 01a6f71..78ad2a4 100644
--- a/ExpMath/src/main/java/net/cofares/model/Add.java
+++ b/ExpMath/src/main/java/net/cofares/model/Add.java
@@ -25,17 +25,17 @@ private Add(Expression e1, Expression e2) {
     }
     @Override
     public Integer evalNum() {
-        return en.evalNum(this);
+        return en.eval(this);
     }
 
     @Override
     public Expression eval() {
-      return Const.create(e1.evalNum()+e2.evalNum());
+        return e.eval(this); 
     }
 
     @Override
     public String show() {
-        return "(" + e1.show() + "+" + e2.show() + ")" ;
+        return es.eval(this);
     }
     
 }
diff --git a/ExpMath/src/main/java/net/cofares/model/Const.java b/ExpMath/src/main/java/net/cofares/model/Const.java
index 2750b47..424a362 100644
--- a/ExpMath/src/main/java/net/cofares/model/Const.java
+++ b/ExpMath/src/main/java/net/cofares/model/Const.java
@@ -20,17 +20,17 @@ private Const(Integer i){
 
     @Override
     public Expression eval() {
-        return this; 
+        return e.eval(this); 
     }
 
     @Override
     public String show() {
-        return "Const:"+getI();
+        return es.eval(this);
     }
 
     @Override
     public Integer evalNum() {
-        return en.evalNum(this);
+        return en.eval(this);
     }
 
     public static void main(String args[]) {
diff --git a/ExpMath/src/main/java/net/cofares/model/EvalNum.java b/ExpMath/src/main/java/net/cofares/model/EvalNum.java
deleted file mode 100644
index 53ae630..0000000
--- a/ExpMath/src/main/java/net/cofares/model/EvalNum.java
+++ /dev/null
@@ -1,24 +0,0 @@
-/*
- * To change this license header, choose License Headers in Project Properties.
- * To change this template file, choose Tools | Templates
- * and open the template in the editor.
- */
-package net.cofares.model;
-
-/**
- * Le visiteur EvalNum
- * @author Acer
- */
-public class EvalNum {
-    Integer evalNum(Const c){
-        return c.getI();
-    }
-    
-    Integer evalNum(Add a){
-        return a.e1.evalNum()+a.e2.evalNum();
-    }
-    
-    Integer evalNum(Sous a){
-        return a.e1.evalNum()-a.e2.evalNum();
-    }
-}
diff --git a/ExpMath/src/main/java/net/cofares/model/Expression.java b/ExpMath/src/main/java/net/cofares/model/Expression.java
index 928eb88..6be78b0 100644
--- a/ExpMath/src/main/java/net/cofares/model/Expression.java
+++ b/ExpMath/src/main/java/net/cofares/model/Expression.java
@@ -1,5 +1,9 @@
 package net.cofares.model;
 
+import net.cofares.visiteur.eval.EvalNum;
+import net.cofares.visiteur.eval.EvalShow;
+import net.cofares.visiteur.eval.EvalToExp;
+
 /**
  * La grammaire
  * 
@@ -27,7 +31,9 @@
  * @author Pascal Fares
  */
 public abstract class Expression {
-    static EvalNum en = new EvalNum(); //Le visiteur Eval NUM TODO: faire que tous les visiteur evaluateur soit une startegie
+    static EvalNum en = new EvalNum(); //Les visiteur 
+    static EvalToExp e = new EvalToExp();
+    static EvalShow es = new EvalShow();
     // à injecter apr un setter, à la création une evaluateur par defaut.
 
     //Factory Expression create : style visiteur
diff --git a/ExpMath/src/main/java/net/cofares/model/ExpressionB.java b/ExpMath/src/main/java/net/cofares/model/ExpressionB.java
index b9c77a6..6466c44 100644
--- a/ExpMath/src/main/java/net/cofares/model/ExpressionB.java
+++ b/ExpMath/src/main/java/net/cofares/model/ExpressionB.java
@@ -5,14 +5,46 @@
  */
 package net.cofares.model;
 
+import net.cofares.visiteur.eval.EvalNum;
+import net.cofares.visiteur.eval.EvalShow;
+import net.cofares.visiteur.eval.EvalToExp;
+
 /**
  * omolememte composition, Abstract Factory + template
  * @author Acer
  */
 public abstract class ExpressionB extends Expression{
 
-    Expression e1;
-    Expression e2;
+    /**
+     * @return the e1
+     */
+    public Expression getE1() {
+        return e1;
+    }
+
+    /**
+     * @param e1 the e1 to set
+     */
+    public void setE1(Expression e1) {
+        this.e1 = e1;
+    }
+
+    /**
+     * @return the e2
+     */
+    public Expression getE2() {
+        return e2;
+    }
+
+    /**
+     * @param e2 the e2 to set
+     */
+    public void setE2(Expression e2) {
+        this.e2 = e2;
+    }
+
+    protected Expression e1;
+    protected Expression e2;
 
 
     /**
@@ -25,6 +57,9 @@ public abstract class ExpressionB extends Expression{
      */
     public static ExpressionB create(String op, Expression e1, Expression e2) {
         en = new EvalNum(); //TODO le passer en injection (c' est en fait une tratégie d'évaluation
+        e=new EvalToExp();
+        es=new EvalShow();
+        
         if (op.equals("+")) {
             return Add.create(e1, e2);
         } else if (op.equals("-")) {
diff --git a/ExpMath/src/main/java/net/cofares/model/Sous.java b/ExpMath/src/main/java/net/cofares/model/Sous.java
index 194eece..0986ffa 100644
--- a/ExpMath/src/main/java/net/cofares/model/Sous.java
+++ b/ExpMath/src/main/java/net/cofares/model/Sous.java
@@ -23,19 +23,20 @@ private Sous(Expression e1, Expression e2) {
         this.e1=e1;
         this.e2=e2;
     }
+    
     @Override
     public Integer evalNum() {
-        return en.evalNum(this);
+        return en.eval(this);
     }
 
     @Override
     public Expression eval() {
-      return Const.create(e1.evalNum()-e2.evalNum());
+        return e.eval(this); 
     }
 
     @Override
     public String show() {
-        return "(" + e1.show() + "-" + e2.show() + ")" ;
+        return es.eval(this);
     }
     
 }
diff --git a/ExpMath/src/main/java/net/cofares/visiteur/eval/Eval.java b/ExpMath/src/main/java/net/cofares/visiteur/eval/Eval.java
new file mode 100644
index 0000000..c7008fd
--- /dev/null
+++ b/ExpMath/src/main/java/net/cofares/visiteur/eval/Eval.java
@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2019 pfares
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package net.cofares.visiteur.eval;
+
+import net.cofares.model.Add;
+import net.cofares.model.Const;
+import net.cofares.model.Sous;
+
+/**
+ *
+ * @author pfares
+ */
+public interface Eval<T> {
+
+    T eval(Const c);
+
+    T eval(Add a);
+
+    T eval(Sous a);
+    
+}
diff --git a/ExpMath/src/main/java/net/cofares/visiteur/eval/EvalNum.java b/ExpMath/src/main/java/net/cofares/visiteur/eval/EvalNum.java
new file mode 100644
index 0000000..350d0b9
--- /dev/null
+++ b/ExpMath/src/main/java/net/cofares/visiteur/eval/EvalNum.java
@@ -0,0 +1,31 @@
+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package net.cofares.visiteur.eval;
+
+import net.cofares.model.Add;
+import net.cofares.model.Const;
+import net.cofares.model.Sous;
+
+/**
+ * Le visiteur EvalNum
+ * @author Pascal Fares
+ */
+public class EvalNum implements Eval<Integer> {
+    @Override
+    public Integer eval(Const c){
+        return c.getI();
+    }
+    
+    @Override
+    public Integer eval(Add a){
+        return a.getE1().evalNum()+a.getE2().evalNum();
+    }
+    
+    @Override
+    public Integer eval(Sous a){
+        return a.getE1().evalNum()-a.getE2().evalNum();
+    }
+}
diff --git a/ExpMath/src/main/java/net/cofares/visiteur/eval/EvalShow.java b/ExpMath/src/main/java/net/cofares/visiteur/eval/EvalShow.java
new file mode 100644
index 0000000..4ef4594
--- /dev/null
+++ b/ExpMath/src/main/java/net/cofares/visiteur/eval/EvalShow.java
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2019 pfares
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package net.cofares.visiteur.eval;
+
+import net.cofares.model.Add;
+import net.cofares.model.Const;
+import net.cofares.model.Sous;
+
+/**
+ * LE visiteur evalShow
+ * @author pfares
+ */
+public class EvalShow implements Eval<String> {
+
+    @Override
+    public String eval(Const c) {
+       return "Const:"+c.getI();
+    }
+
+    @Override
+    public String eval(Add a) {
+       return "("+a.getE1().show()+"+"+a.getE2().show()+ ")";
+    }
+
+    @Override
+    public String eval(Sous a) {
+        return "("+a.getE1().show()+"-"+a.getE2().show()+ ")";
+    }
+    
+}
diff --git a/ExpMath/src/main/java/net/cofares/visiteur/eval/EvalToExp.java b/ExpMath/src/main/java/net/cofares/visiteur/eval/EvalToExp.java
new file mode 100644
index 0000000..eaefdb5
--- /dev/null
+++ b/ExpMath/src/main/java/net/cofares/visiteur/eval/EvalToExp.java
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2019 pfares
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package net.cofares.visiteur.eval;
+
+import net.cofares.model.Add;
+import net.cofares.model.Const;
+import net.cofares.model.Expression;
+import net.cofares.model.Sous;
+
+/**
+ * LE visiteur eval
+ * @author pfares
+ */
+public class EvalToExp implements Eval<Expression> {
+
+    @Override
+    public Expression eval(Const c) {
+        return c; 
+    }
+
+    @Override
+    public Expression eval(Add a) {
+        return Const.create(a.getE1().evalNum()+a.getE2().evalNum());
+    }
+
+    @Override
+    public Expression eval(Sous a) {
+        return Const.create(a.getE1().evalNum()-a.getE2().evalNum());
+    }
+    
+}