Throw an exception when constructing a query with empty string as criteria #1290

Author: lling

marklogic-client-api/src/main/java/com/marklogic/client/impl/StringQueryDefinitionImpl.java

@@ -31,6 +31,9 @@ public String getCriteria() {
 
   @Override
   public void setCriteria(String criteria) {
+    if (criteria.length() == 0) {
+      throw new IllegalArgumentException("Criteria cannot be an empty string.");
+    }
     this.criteria = criteria;
   }