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ArangoDB Java Driver
There is a newer version: 7.15.0
/*
 * Copyright (C) 2012 tamtam180
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.arangodb;

import java.util.Iterator;
import java.util.NoSuchElementException;

import com.arangodb.entity.CursorEntity;

/**
 * @author tamtam180 - kirscheless at gmail.com
 *
 */
public class CursorResultSet implements Iterable {

  private String database;
  private transient InternalCursorDriver cursorDriver;
  private transient Class[] clazz;
  private transient CursorEntity entity;
  private transient int pos;
  private int totalCount;
  private transient Iterator itr;
  
  public CursorResultSet(String database, InternalCursorDriver cursorDriver, CursorEntity entity, Class ...clazz) {
    this.database = database;
    this.cursorDriver = cursorDriver;
    this.clazz = clazz;
    this.entity = entity;
    this.totalCount = entity == null ? 0 : entity.getCount();
    this.pos = 0;
    this.itr = new CursorIterator();
  }

  public Iterator iterator() {
    return new CursorIterator();
  }
  
  public boolean hasNext() {
    return itr.hasNext();
  }
  
  public T next() {
    return itr.next();
  }
  
  public void close() throws ArangoException {
    long cursorId = entity.getCursorId();
    cursorDriver.finishQuery(database, cursorId);
  }
  
  public int getTotalCount() {
    return totalCount;
  }
  
  private void updateEntity() throws ArangoException {
    long cursorId = entity.getCursorId();
    this.entity = cursorDriver.continueQuery(database, cursorId, this.clazz);
    this.pos = 0;
  }
  
  public class CursorIterator implements Iterator {

    public boolean hasNext() {
      if (entity == null) {
        return false;
      }
      if (pos < entity.size()) {
        return true;
      }
      if (entity.hasMore()) {
        return true;
      }
      return false;
    }

    public T next() {
      if (hasNext()) {
        if (pos >= entity.size()) {
          try {
            updateEntity();
          } catch (ArangoException e) {
            throw new IllegalStateException(e);
          }
        }
        return entity.get(pos++);
      }
      throw new NoSuchElementException();
    }

    public void remove() {
      throw new UnsupportedOperationException("remove does not support!!");
    }
    
  }
  
}