meta query builder update
diff --git a/src/main/java/de/ids_mannheim/korap/query/serialize/MetaQueryBuilder.java b/src/main/java/de/ids_mannheim/korap/query/serialize/MetaQueryBuilder.java
index 09c3c1a..0e41a76 100644
--- a/src/main/java/de/ids_mannheim/korap/query/serialize/MetaQueryBuilder.java
+++ b/src/main/java/de/ids_mannheim/korap/query/serialize/MetaQueryBuilder.java
@@ -30,8 +30,8 @@
      * @param rightType
      * @return
      */
-    public MetaQueryBuilder setContext(Integer left, String leftType,
-                                       Integer right, String rightType) {
+    public MetaQueryBuilder setSpanContext(Integer left, String leftType,
+                                           Integer right, String rightType) {
         this.spanContext = new SpanContext(left, leftType, right, rightType);
         return this;
     }
@@ -47,7 +47,7 @@
      * @param context
      * @return
      */
-    public MetaQueryBuilder setContext(String context) {
+    public MetaQueryBuilder setSpanContext(String context) {
         if (context.startsWith("s") | context.startsWith("p"))
             this.spanContext = new SpanContext(context);
         else {
@@ -69,7 +69,7 @@
         if (pageLength != null)
             this.addEntry("count", pageLength);
         if (ctx != null)
-            this.setContext(ctx);
+            this.setSpanContext(ctx);
         if (cutoff != null)
             this.addEntry("cutOff", cutoff);
         return this;
@@ -82,7 +82,8 @@
     }
 
     public Map raw() {
-        meta.putAll(this.spanContext.raw());
+        if (this.spanContext != null)
+            meta.putAll(this.spanContext.raw());
         return meta;
     }
 
diff --git a/src/main/java/de/ids_mannheim/korap/query/serialize/QuerySerializer.java b/src/main/java/de/ids_mannheim/korap/query/serialize/QuerySerializer.java
index 950befa..a048ecf 100644
--- a/src/main/java/de/ids_mannheim/korap/query/serialize/QuerySerializer.java
+++ b/src/main/java/de/ids_mannheim/korap/query/serialize/QuerySerializer.java
@@ -157,7 +157,7 @@
             String cli, String cri, int cls, int crs,
             int num, int pageIndex) {
         MetaQueryBuilder meta = new MetaQueryBuilder();
-        meta.setContext(cls, cli, crs, cri);
+        meta.setSpanContext(cls, cli, crs, cri);
         meta.addEntry("startIndex", pageIndex);
         meta.addEntry("count", num);
         this.meta = meta.raw();
@@ -168,7 +168,7 @@
         MetaQueryBuilder meta = new MetaQueryBuilder();
         meta.addEntry("startIndex", pageidx);
         meta.addEntry("count", num);
-        meta.setContext(context);
+        meta.setSpanContext(context);
         return this;
     }