Index: lutinutil/src/java/org/codelutin/util/MyProperties.java
diff -u lutinutil/src/java/org/codelutin/util/MyProperties.java:1.1 lutinutil/src/java/org/codelutin/util/MyProperties.java:1.2
--- lutinutil/src/java/org/codelutin/util/MyProperties.java:1.1	Sun Dec  9 20:01:42 2007
+++ lutinutil/src/java/org/codelutin/util/MyProperties.java	Mon Dec 10 02:35:41 2007
@@ -26,6 +26,7 @@
 
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.OutputStream;
 import java.io.Reader;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -227,10 +228,20 @@
         if (tmp != null) {
             tmp.clear();
         }
+        clearUnsafeData();
+        keys.clear();
+    }
+
+    /**
+     * clear the instance unsafeData.
+     * <p/>
+     * After the method invocation, the {@link #isSafe()}'s method's return is
+     * always <code>true</code>.
+     */
+    public void clearUnsafeData() {
         if (unsafeData != null) {
             unsafeData.clear();
         }
-        keys.clear();
     }
 
     /**
@@ -311,6 +322,53 @@
         return this;
     }
 
+    /**
+     * TODO We should not save unsafe data, so perform a clearUnsafeData before all.
+     * Save current configuration in a simple properties file.
+     * <p/>
+     * Each valid property is saved using the his key given by the method
+     * {@link MyPropertyKey#getKey()} for his entry.
+     * <p/>
+     * Unsafe data are stored as they are.
+     *
+     * @param out      where to store
+     * @param comments comment to add in file
+     * @throws IOException if any problem while saving
+     */
+    public void store(OutputStream out, String comments) throws IOException {
+        getTmp().clear();
+        try {
+            if (!isEmpty()) {
+                for (T key : getKeys()) {
+                    MyPropertyKey entry = getManager().getEntry((MyPropertyDef) key, false);
+                    Object val = data.get(key);
+                    tmp.put(entry.getKey(), val == null ? "" : val.toString());
+                }
+            }
+            if (!isSafe()) {
+                for (Object key : getUnsafeDataKeys()) {
+                    Object val = unsafeData.get(key);
+                    tmp.put(key, val == null ? "" : val.toString());
+                }
+            }
+            tmp.store(out, comments);
+        } finally {
+            tmp.clear();
+        }
+    }
+
+    public Properties toProperties() {
+        Properties result = new Properties();
+        if (!isEmpty()) {
+            for (T key : getKeys()) {
+                MyPropertyKey entry = getManager().getEntry((MyPropertyDef) key, false);
+                Object val = data.get(key);
+                result.put(entry.getKey(), val == null ? "" : val.toString());
+            }
+        }
+        return result;
+    }
+
     @Override
     public String toString() {
         StringBuilder s = new StringBuilder(super.toString()).append("<size:").append(size()).append('/').append(universe.size());