org.eclipse.blockchain.core/src/org/eclipse/blockchain/core/ListCreator.java

/*
 * Copyright (c) Robert Bosch GmbH. All rights reserved.
 */
package org.eclipse.blockchain.core;

import java.util.ArrayList;
import java.util.List;

/**
 * @author ADG5COB
 */
@SuppressWarnings("unchecked")
public class ListCreator {

  List<Object> currentList;
  List<Object> parentList;

  /**
   * This returns the list that is currently processed
   *
   * @param depth - The current dimension level
   * @param isNew - if true creates a new list
   * @return - The List
   */
  public List<Object> getCurrentList(final int depth, final boolean isNew) {
    if (isNew) {
      this.currentList = (List<Object>) assignList(depth);
    }
    return this.currentList;
  }

  /**
   * Adds the element to the current list
   *
   * @param depth - The current dimension level
   * @param isNew - if true creates a new list
   * @param element - The element to be added
   */
  public <T> void addToCurrentList(final int depth, final boolean isNew, final T element) {
    getCurrentList(depth, isNew).add(element);
  }

  /**
   * This returns the currently processed list's parent container
   *
   * @param depth - The current dimension level
   * @param isNew - if true creates a new list
   * @return - The List
   */
  public List<Object> getParentList(final int depth, final boolean isNew) {
    if (isNew) {
      this.parentList = (List<Object>) assignList(depth + 1);
    }
    return this.parentList;
  }

  /**
   * Adds the current list to the parent list
   *
   * @param depth - The current dimension level
   * @param isNew - if true creates a new list
   */
  public void addToParentList(final int depth, final boolean isNew) {
    getParentList(depth + 1, isNew).add(getCurrentList(depth, isNew));
  }

  /**
   * @return - true if current list is empty, false otherwise
   */
  public boolean isCurrentListEmpty() {
    return (this.currentList == null) || this.currentList.isEmpty();
  }

  /**
   * @return - true if current list is empty, false otherwise
   */
  public boolean isParentListEmpty() {
    return (this.parentList == null) || this.parentList.isEmpty();
  }

  /**
   * This method is used to split the current list according to the given dimension and package's into the parent list
   *
   * @param pList - The parent container
   * @param depth - The current dimension depth
   * @param currentDimension - The size of current depth
   * @return - The segmented list
   */
  public List<Object> segmentList(final Object pList, final int depth, final int currentDimension) {
    getParentList(depth, true);
    getCurrentList(depth, true);
    List<Object> current = (List<Object>) pList;
    int cnt = 1;
    for (int i = 0; i < current.size(); i++) {
      if (cnt <= currentDimension) {
        this.currentList.add(current.get(i));
      }
      else {
        this.parentList.add(this.currentList);
        getCurrentList(depth, true);
        this.currentList.add(current.get(i));
        cnt = 1;
      }
      cnt++;
      if (i == (current.size() - 1)) {// This means the last iteration
        this.parentList.add(this.currentList);
      }
    }
    return this.parentList;
  }

  private Object assignList(final int depth) {
    switch (depth) {
      case 1:
        List<?> theList1 = new ArrayList<>();
        return theList1;
      case 2:
        List<List<?>> theList2 = new ArrayList<>();
        return theList2;
      case 3:
        List<List<List<?>>> theList3 = new ArrayList<>();
        return theList3;
      case 4:
        List<List<List<List<?>>>> theList4 = new ArrayList<>();
        return theList4;
      case 5:
        List<List<List<List<List<?>>>>> theList5 = new ArrayList<>();
        return theList5;
      case 6:
        List<List<List<List<List<List<?>>>>>> theList6 = new ArrayList<>();
        return theList6;
      case 7:
        List<List<List<List<List<List<List<?>>>>>>> theList7 = new ArrayList<>();
        return theList7;
      case 8:
        List<List<List<List<List<List<List<List<?>>>>>>>> theList8 = new ArrayList<>();
        return theList8;
      case 9:
        List<List<List<List<List<List<List<List<List<?>>>>>>>>> theList9 = new ArrayList<>();
        return theList9;
      case 10:
        List<List<List<List<List<List<List<List<List<List<?>>>>>>>>>> theList10 = new ArrayList<>();
        return theList10;
      case 11:
        List<List<List<List<List<List<List<List<List<List<List<?>>>>>>>>>>> theList11 = new ArrayList<>();
        return theList11;
      case 12:
        List<List<List<List<List<List<List<List<List<List<List<List<?>>>>>>>>>>>> theList12 = new ArrayList<>();
        return theList12;
      case 13:
        List<List<List<List<List<List<List<List<List<List<List<List<List<?>>>>>>>>>>>>> theList13 = new ArrayList<>();
        return theList13;
      case 14:
        List<List<List<List<List<List<List<List<List<List<List<List<List<List<?>>>>>>>>>>>>>> theList14 =
            new ArrayList<>();
        return theList14;
      case 15:
        List<List<List<List<List<List<List<List<List<List<List<List<List<List<List<?>>>>>>>>>>>>>>> theList15 =
            new ArrayList<>();
        return theList15;
      default:
        throw new UnsupportedOperationException("Stack too deep maximum limit is 15");
    }
  }
}