DataIterator Class

package com.collager.trillo.model;

import java.util.List;
import java.util.Map;
import com.collager.trillo.pojo.Result;
import com.collager.trillo.util.BaseApi;
import com.collager.trillo.util.CoreDSUtil;
import com.collager.trillo.util.DSApi;
import com.collager.trillo.util.LogApi;
import com.collager.trillo.util.Util;

public class DataIterator {
 
  private DataRequest dataRequest = null;
  private DataResult dataResult = null;
  private Object result = null;
  private int index = 0;
  private boolean iteratorEnded = false;
  private boolean noMorePage = false;
  private boolean orderById = false;
  private String originalQuery = null;
  private Object lastId;
  private String idAttrName = "id";
  private String dsType = CoreDSUtil.MYSQL;
  private boolean firstPage = true;
  private int nextStart = 1;
  private String countQuery = null;
  private int totalItems = -1;
  private boolean errored = false;
  private String message = null;
  
   public DataIterator(String className, String where, String orderBy, int start, int pageSize) {

    dataRequest = new DataRequest();
    dataRequest.setClassName(className);
    dataRequest.setWhere(where);
    dataRequest.setOrderBy(orderBy);
    dataRequest.setStart(start);
    dataRequest.setSize(pageSize);
    dataRequest.setUsingRowLimits(true);
    dataRequest.setAppName(BaseApi.app(className));
    dataRequest.setDsName(BaseApi.ds(className));
    dataRequest.setClassName(BaseApi.cls(className));
  }
  
  … more constructors …  
  public DataIterator(String className, Exp filter, String orderBy, int start, int pageSize) {
    … … …
  }
  
  
  public DataIterator(int start, int pageSize, String sqlQuery) {
    // using sql query
    dataRequest = new DataRequest();
    dataRequest.setSql(sqlQuery);
    dataRequest.setStart(start);
    dataRequest.setSize(pageSize);
    dataRequest.setUsingRowLimits(true);
  }
  
  public DataIterator(String appName, String dsName, int start, int pageSize, String sqlQuery) {
    … … …
  }
  
    
  … … …

  public DataRequest getDataRequest() {
    return dataRequest;
  }
  
  public DataResult getDataResult() {
    return dataResult;
  }

  public Object getResult() {
    return result;
  }
  
  public Object hasError() {
    return errored;
  }

  public Object getMessage() {
    return message;
  }
  
  public int getIndex() {
    return index;
  }

  public Result initialize() {
    if (iteratorEnded) {
      return Result.getFailedResult("DataIterator has ended");
    }
    if (dataResult == null) {
      fetch();
    }
    
    if (errored) {
      return Result.getFailedResult(message);
    }
    
    return Result.getSuccessResult();
  }
  
  @SuppressWarnings("unchecked")
  public Object getNext() {
    // return next record
  }

  public boolean hasNext() {
    // checks if has next record
  }

  public List<Map<String, Object>> getPage() {
    // return a page
  }
  
  public boolean hasPage() {
    // returns if more pages pending to iterate
  }
  
  private void fetch() {
    // internal implementation
  }
  
  @SuppressWarnings("unchecked")
  private DataResult retrievePage() {
    // internal implementation
  }

  public int getTotalItems() {
    if (totalItems != -1) {
      return totalItems;
    }
    if (iteratorEnded) {
      return totalItems;
    }
    if (dataResult == null) {
      fetch();
    }
    return totalItems;
  }

  public String getCountQuery() {
    return countQuery;
  }

  // to get the totalCount
  public void setCountQuery(String countQuery) {
    this.countQuery = countQuery;
  }
}