LoadOnGetList20131227.java

package com.jiuqi.mobile.nigo.comeclose.bean;

import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.List;

import com.google.gson.annotations.Expose;
import com.google.gson.internal.$Gson$Types;
import com.jiuqi.mobile.nigo.comeclose.bean.app.news.CarTaskNewsBean;
import com.jiuqi.mobile.nigo.comeclose.exception.IndexOutException;
import com.jiuqi.mobile.nigo.comeclose.manager.ILoadDataHandler;
import com.jiuqi.mobile.nigo.comeclose.manager.ManagerFactory;
import com.jiuqi.mobile.nigo.comeclose.manager.app.INewsManager;
import com.jiuqi.mobile.nigo.comeclose.manager.app.SelectNewsKey;

/**
 * 返回结果集封装，此类包含数据请求。不利于用户远程使用。<br/>
 * 客户端访问时，请谨慎使用。。。使用前请于本人沟通<br/>
 * 客户端使用方法：<br/>
 * void handler(){<br/>
 * String session = "";<br/>
 * INewsManager manager = ManagerFactory.instanceManager(INewsManager.class,
 * session );<br/>
 * int pageSize = 15;<br/>
 * long startIndex = 0;<br/>
 * SelectNewsKey key = new SelectNewsKey(pageSize);<br/>
 * key.setStartIndex(startIndex);<br/>
 * iterateList(manager, pageSize, startIndex, key);<br/>
 * //第二次请求<br/>
 * startIndex += pageSize;<br/>
 * key.setStartIndex(startIndex);<br/>
 * iterateList(manager, pageSize, startIndex, key);<br/>
 * ...<br/>
 * }<br/>
 * private void iterateList(INewsManager manager, int pageSize,<br/>
 * long startIndex, SelectNewsKey key) {<br/>
 * LoadOnGetList<CarTaskNewsBean> list = manager.get(CarTaskNewsBean.class,
 * key);<br/>
 * for(long i=startIndex; i<Math.min(pageSize+startIndex,
 * list.getTotalCount());i++){<br/>
 * CarTaskNewsBean bean = list.get(startIndex);<br/>
 * }<br/>
 * }<br/>
 * 
 * @author modi
 * 
 * @param <T>
 */
public class LoadOnGetList20131227<T> {
	@Expose(deserialize = false, serialize = false)
	private ILoadDataHandler<T> loadData;
	private int size;
	// private final SelectKey key;
	private List<T> list = new ArrayList<T>();
	private long startIndex;
	private long totalCount;
	private boolean isEnd = false;

	void mobileFoo() {
		String session = "";
		INewsManager manager = ManagerFactory.instanceManager(
				INewsManager.class, session);
		int pageSize = 15;
		long startIndex = 0;
		SelectNewsKey key = new SelectNewsKey(pageSize);
		key.setStartIndex(startIndex);
		iterateList(manager, pageSize, startIndex, key);
		// 第二次请求
		startIndex += pageSize;
		key.setStartIndex(startIndex);
		iterateList(manager, pageSize, startIndex, key);
	}

	private void iterateList(INewsManager manager, int pageSize,
			long startIndex, SelectNewsKey key) {
		LoadOnGetList<CarTaskNewsBean> list = manager.get(
				CarTaskNewsBean.class, key);
		for (long i = startIndex; i < Math.min(pageSize + startIndex,
				list.getTotalCount()); i++) {
			CarTaskNewsBean bean = list.get(startIndex);
			System.out.println(bean);
		}
	}

	public LoadOnGetList20131227() {
	}

	public LoadOnGetList20131227(List<T> list) {
		this.list = list;
		this.totalCount = list.size();
		this.startIndex = list.size();
		this.size = list.size();
	}

	public LoadOnGetList20131227(ILoadDataHandler<T> loadData, SelectKey key) {
		this.size = key.getSize();
		this.loadData = loadData;
		this.startIndex = 0;
		this.startIndex = key.getStartIndex();
		try {
			load();
		} catch (IndexOutException e) {
		}
	}

	public T get(long index) throws IndexOutException {
		if (isEnd || index < 0) {
			throw new IndexOutException();
		}
		if (index >= startIndex) {
			load();
		}
		if (index < startIndex - list.size()) {
			while (index < startIndex - list.size()) {
				startIndex = startIndex - size;
				startIndex = startIndex < 0 ? 0 : startIndex;
			}
			load();
		}
		int i = (int) (index + list.size() - startIndex);
		if (i < 0) {
			throw new IndexOutException();
		}
		return list.get(i);
	}

	public long getTotalCount() {
		return totalCount;
	}

	public void setTotalCount(long totalCount) {
		this.totalCount = totalCount;
	}

	// public SelectKey getKey() {
	// return key;
	// }
	private void load() throws IndexOutException {
		if (null == loadData) {
			throw new IndexOutException();
		}
		list = loadData.getData(startIndex, startIndex + size);
		if (list.isEmpty()) {
			isEnd = true;
			setTotalCount(startIndex);
			throw new IndexOutException();
		} else {
			setTotalCount(loadData.getTotalCount());
			startIndex += list.size();
		}
	}

	/**
	 * 服务端禁用，仅限android客户端使用
	 * 
	 * @return
	 */
	public List<T> getList() {
		return list;
	}

	public Type getType() {
		Type superclass = getClass().getGenericSuperclass();
		if (superclass instanceof Class) {
			throw new RuntimeException("Missing type parameter.");
		}
		ParameterizedType parameterized = (ParameterizedType) superclass;
		return $Gson$Types
				.canonicalize(parameterized.getActualTypeArguments()[0]);
	}
}