anchor.diff:  ----
   
   
  -You can now use Predicate, QueryModifiers, OrderSpecifier or Pageable +
  -in the Querydsl API, or in JPAQuery/MongoQuery of QEmployee, +
  +You can now use Expression, Predicate, QueryModifiers, OrderSpecifier or Pageable +
  +in the Querydsl API, or in JPAQuery, +
   or in the Spring Data JPA/Mongo Repository.
   
   === A MORE APPROPRIATE WIKI
  
positive.code: 
  _This library brings the convenience of SQL declarative nature to restful APIs in the form of RSQL
  but without the danger of sql injection by using a typesafe mapping of allowed field paths defined
  via integration with querydsl library. Like sql, it supports clauses such as select, filter, pagination 
  and sorting that can easily be represented in http request parameters_.
  
  _It primarily supports JPA model but if possible will strive to handle other kinds of database such as MongoDB.
  
negative.code: [source,java]
  ----
  
  String rqlSelect = "select(contact.name, contact.age)";
  String rqlFilter = "(contact.age =='1' and contact.name == 'A*') or (contact.age > '1'  and contact.bday == '2015-05-05')";
  String limit = "limit(0, 10)";
  String sort = "sort(+contact.name)";
  
  RqlInput rqlInput = new RqlInput()
          .setSelect(rqlSelect)
          .setFilter(rqlFilter)
          .setLimit(limit)
          .setSort(sort);
  
  Map<String , Path> pathMapping = ImmutableMap.<String, Path>builder()
          .put("contact.name", QContactDocument.contactDocument.name)
          .put("contact.age", QContactDocument.contactDocument.age)
          .put("contact.bday", QContactDocument.contactDocument.bday)
          .build();
  
  QuerydslMappingResult querydslMappingResult = querydslRqlParser.parse(rqlInput, new QuerydslMappingParam().setRootPath(QContactDocument.contactDocument).setPathMapping(pathMapping));
  
  Expression selectExpression = querydslMappingResult.getProjection();
  Predicate predicate = querydslMappingResult.getPredicate();
  
  QueryModifiers querydslPage = querydslMappingResult.getPage();
  