diff --git a/src/main/java/org/gcube/nlphub/NLPMapper.java b/src/main/java/org/gcube/nlphub/NLPMapper.java
index c63479e..05b40c4 100644
--- a/src/main/java/org/gcube/nlphub/NLPMapper.java
+++ b/src/main/java/org/gcube/nlphub/NLPMapper.java
@@ -67,18 +67,27 @@ public class NLPMapper extends HttpServlet {
 		response.setCharacterEncoding("utf-8");
 		token = Constants.getToken(request, devMode);
 		String documentLink = request.getParameter("plink"); // link to text file (workspace)
+		System.out.println("documentLink\n: " + documentLink);
 		String toBeMap = request.getParameter("tobemap");
-		System.out.println("tobemap: " + toBeMap);
+		System.out.println("tobemap:\n" + toBeMap);
 		String[] tokens; 
 		if(toBeMap.indexOf("|") > 0)
-			tokens = toBeMap.split("|");
+			tokens = toBeMap.split("\\|");
 		else {
 			tokens = new String[1];
 			tokens[0] = toBeMap;
 		}
+		
 		String annotations = request.getParameter("annotations");
+		System.out.println("annotations\n: " + annotations);
 		String language = request.getParameter("lang");
 		PrintWriter writer = response.getWriter();
+		System.out.println("language\n: " + language);
+		
+		System.out.println("tokens length: " + tokens.length);
+		for(int u=0; u<tokens.length; u++) {
+			System.out.println("[" + u + "] " + tokens[u]);
+		}
 		try {
 			String text = getDocument(documentLink);
 			
@@ -165,6 +174,5 @@ public class NLPMapper extends HttpServlet {
 		String link = ws.getPublicLink(fileName, token);
 		return link;
 	}
-	
-	 
+
 }
diff --git a/src/main/webapp/index.jsp b/src/main/webapp/index.jsp
index 9b4bbc1..2e3eda4 100644
--- a/src/main/webapp/index.jsp
+++ b/src/main/webapp/index.jsp
@@ -17,6 +17,7 @@
 <script type="text/javascript" src="js/materialize.min.js"></script>
 <script type="text/javascript" src="js/jquery.simple.websocket.min.js"></script>
 <script type="text/javascript" src="js/jquery.uploadfile.min.js"></script>
+<script type="text/javascript" src="js/merge.js"></script>
 <!-- <script type="text/javascript" src="js/main.js"></script> -->
 <!-- scripting code -->
 <script type="text/javascript">
@@ -228,7 +229,7 @@
 				if (a[j].length > 0) {
 					var thereIs = false;
 					for (k in annotations) {
-						if (annotations[k].toUpperCase == a[j].toUpperCase()) {
+						if (annotations[k].toUpperCase() == a[j].toUpperCase()) {
 							thereIs = true;
 							break;
 						}
@@ -245,7 +246,7 @@
 				if (langs[j].length > 0) {
 					var thereIs = false;
 					for (k in languages) {
-						if (languages[k].toUpperCase == langs[j].toUpperCase()) {
+						if (languages[k].toUpperCase() == langs[j].toUpperCase()) {
 							thereIs = true;
 							break;
 						}
@@ -387,6 +388,7 @@
 		parameters += "&plink=" + encodeURI(publicLink);
 		parameters += "&lang=" + $("#language-select").val();
 		parameters += "&tobemap=" + encodeURI(tobemap);
+		console.log(parameters);
 
 		$.ajax({
 			url : "/nlphub/nlphub-mapper-servlet?" + parameters,
@@ -394,10 +396,15 @@
 			async : true,
 			success : function(data, stato) {
 				console.log(data);
-				$("#reset-upload").hide();
-				savedAnnotations = "";
-				publicLink = null;
-				showResult(data);
+				if((typeof (data.response) != "undefined") && (data.response.trim().toUpperCase() == "ERROR")) {
+					alert ("ERROR\n" + data.message);
+				}
+				else {
+					$("#reset-upload").hide();
+					savedAnnotations = "";
+					publicLink = null;
+					showResult(data);
+				}
 			},
 			error : function(richiesta, stato, errori) {
 				$("#reset-upload").hide();
@@ -478,7 +485,7 @@
 		var indices = getIndices(annotation);
 		var indexedText = "";
 
-		if (indices.length == 0) {
+		if ((typeof (indices) == 'undefined' ) || (indices.length == 0)) {
 			indexedText = resultText;
 			indexedText = indexedText.replace(/\n/g, "<br>");
 			$("#result-text-div").append("<p>" + indexedText + "</p>");
@@ -532,8 +539,10 @@
 	mergeIndices = function(indices) {
 		// GESTIONE MULTIDIMENSIONALE DA FARE !!!!
 		var newIndices = []
-		if (indices.length == 1)
+		if (indices.length <= 1)
 			newIndices = indices[0];
+		else
+			newIndices = mergeAll(indices);
 		return newIndices;
 	}
 
diff --git a/src/main/webapp/js/merge.js b/src/main/webapp/js/merge.js
new file mode 100644
index 0000000..5fe08f7
--- /dev/null
+++ b/src/main/webapp/js/merge.js
@@ -0,0 +1,108 @@
+mergeSegment = function(segment1, segment2) {
+	var merged = [];
+	
+	if(segment1[0] <= segment2[0]) {
+		if(segment1[1] < segment2[0]) {
+			merged = [segment1, segment2];
+		}
+		else {
+			if(segment1[1] >= segment2[1])
+				merged = [segment1];
+			else 
+				merged = [[segment1[0], segment2[1]]];
+		}
+	}
+	else {
+		if(segment2[1] < segment1[0]) {
+			merged = [segment2, segment1];
+		}
+		else {
+			if(segment2[1] >= segment1[1])
+				merged = [segment2];
+			else 
+				merged = [[segment2[0], segment1[1]]];
+		}
+	}
+	return merged;
+}
+
+compareSegment = function(segment1, segment2) {
+	// inclusi o coincidenti
+	if((segment1[0] >= segment2[0]) && (segment1[1] <= segment2[1]))
+		return 0;
+	if((segment1[0] <= segment2[0]) && (segment1[1] >= segment2[1]))
+		return 0;
+	// esterni
+	if((segment1[1] < segment2[0]) || ((segment1[0] > segment2[1])))
+		return 1;
+	// intersecanti
+	return -1;
+}
+
+compareSegments = function(s1, s2) {
+	return (s1[0] - s2[0]);
+}
+
+cleanSegmentList = function(list) {
+	var cleaned = [];
+	for(var i=0; i<list.length; i++) {
+		if(cleaned.length == 0)
+			cleaned[cleaned.length] = list[i];
+		else {
+			var found = false;			
+			for(var j=0; j<cleaned.length; j++) {
+				if(compareSegment(cleaned[j], list[i]) == 0) {
+					if(cleaned[j][0] > list[i][0])	
+						cleaned[j] = list[i];
+					found = true;
+					break;
+				}
+				if(compareSegment(cleaned[j], list[i]) < 0) {
+					if(cleaned[j][0] <= list[i][0]) 
+						cleaned[j] = [cleaned[j][0], list[i][1]];
+					else
+						cleaned[j] = [list[i][0], cleaned[j][1]];
+					found = true;
+				}
+			}
+			if(!found) cleaned[cleaned.length] = list[i];
+		}
+	 }
+	return cleaned;
+}
+
+compareSegmentList = function(list1, list2) {
+	if(list1.length != list2.length)
+		return false;
+	for(var i=0; i<list1.length; i++)
+		if((list1[i][0] != list2[i][0]) || (list1[i][1] != list2[i][1]))
+			return false;
+	return true;
+}
+
+
+
+mergeAll = function(indices) {
+	var m = [];
+	for(var i=0; i<indices[0].length; i++) {
+	 	for(var j=1; j<indices.length; j++) {
+	 		for(var k=0; k<indices[j].length; k++) {
+	 			var res = mergeSegment(indices[0][i], indices[j][k]);
+	 			for(var u=0; u<res.length; u++) 
+	 				m[m.length] = res[u];
+	 		}
+	 	}
+	}
+	
+	var end = false;
+	var counter = 1;
+	while(!end) {
+		var old = m.slice();
+		m = cleanSegmentList(m);
+		//console.log(m);
+		end = compareSegmentList(old, m);
+		if(counter == 100)
+			end = true;
+	}
+	return m.sort(compareSegments);
+}
diff --git a/src/main/webapp/merge.html b/src/main/webapp/merge.html
new file mode 100644
index 0000000..ec29516
--- /dev/null
+++ b/src/main/webapp/merge.html
@@ -0,0 +1,58 @@
+<!DOCTYPE html>
+<html>
+<head>
+<meta charset="UTF-8">
+<title>Merge TEST</title>
+<script type="text/javascript" src="js/merge.js"></script>
+
+<script type="text/javascript">
+var indices = [
+	[[0,5], [7,9], [15,19]],
+	[[6,10]],
+	[[1,6], [9,16], [21,23]],
+	[[7,9], [12,13]]
+];
+
+//var newIndices = mergeIndices(indices);
+
+//console.log(newIndices);
+// answer is: [0,19], [21,23]
+
+indices = [
+	[[7,19], [21,25]],
+	[[1,5], [18,22]]
+];
+//answer is: [1,5], [7,25]
+
+indices = [
+	[[7,16], [21,25]],
+	[[1,5], [18,22]]
+];
+//answer is: [1,5], [7,16], [18,25]
+
+indices = [
+	[[7,16], [21,25]],
+	[[1,5], [18,22]],
+	[[2,30]]
+];
+//answer is: [1,30]
+
+indices = [
+	[[1,4], [5, 8], [21,25]],
+	[[1,5], [18,22]],
+	[[0,2], [11,15], [27,31]]
+];
+//answer is: [0,8],[11,15],[18,25],[27,31]
+
+
+var mm = mergeAll(indices);
+
+console.log(mm);
+
+
+</script>
+</head>
+<body>
+
+</body>
+</html>
\ No newline at end of file