title: Limit and skip options in MongoItemReader
body: <p>In my spring batch application I need to migrate data from mongoDB to postgreSQL.
  I'm using <a href="http://docs.spring.io/spring-batch/trunk/apidocs/org/springframework/batch/item/data/MongoItemReader.html" rel="nofollow">MongoItemReader</a> for reading data. This reader can be configured by setting several properties such as query, sort, fields, etc. But I don't want to read all data from collection, I want to read only part of it and get this part by 'skip' and 'limit' cursor properties. Is there any ability to do that via this class or I should use other mongo reader to solve my problem?</p>
  
  <p>Here the code of my reader class which extends MongoItemReader.</p>
  
  <pre><code>public class MongoMigrateItemReader&lt;T extends Migratable&gt; extends MongoItemReader&lt;T&gt; implements ItemReader&lt;T&gt; {
      protected String collectionName;
      @Autowired
      MongoTemplate mongoTemplate;
  
      public MongoMigrateItemReader() {
      }
  
      @PostConstruct
      public void init() {
          Type type = ((ParameterizedType) this.getClass().getGenericSuperclass()).getActualTypeArguments()[0];
          Class&lt;T&gt; clazz = (Class&lt;T&gt;) type;
          this.setTemplate(mongoTemplate);
          this.setTargetType(clazz);
          this.setCollection(collectionName);
          this.setQuery("{}");
          HashMap&lt;String, Sort.Direction&gt; sort = new HashMap&lt;&gt;();
          sort.put("_id", Sort.Direction.ASC);
          this.setSort(sort);
      }
  </code></pre>
  
  <p>}</p>
  
  <p>I want to set limit and skip options in init() method </p>