OrmLite可以幫助我們將會數據庫操作，不用自己去寫SQL語句，而且設置它跟使用Sqlite一樣的方式，它是一種關系型數據，我比較喜歡的就是它能夠幫助我判斷數據表項是更新還是創建等操作，不需要自己去寫大量的SQL語句去判斷，下面介紹一下它的使用文檔以及一些基本的注意點：

官方網址：http://ormlite.com/

JavaDOC地址：http://ormlite.com/javadoc/ormlite-android/

開發文檔地址：http://ormlite.com/javadoc/ormlite-core/doc-files/ormlite.html

一、建立模型

首先創建一個Model，作為一個數據表，在Android中我使用的是實現Parcelable，代碼如下：

package com.jwzhangjie.capricorntv.bean;

import com.j256.ormlite.field.DatabaseField;
import com.j256.ormlite.table.DatabaseTable;

import android.os.Parcel;
import android.os.Parcelable;

/**
 * 
 * @author zj 包含視頻的參數 視頻的名字 "channel_id":9, "channel_name":"湖南衛視",
 *         "icon_url":"http://tv.togic.com:8080/ShowTimeService/images/182.png",
 *         "province":"湖南", "mode":"SD", "url":
 *         "http://live.gslb.letv.com/gslb?stream_id=hunan&tag=live&ext=m3u8&sign=live_tv&platid=10&splatid=1012&temporarykey=db7c39a0ee39ab2d4d2e781d5"
 *         ,
 *         "second_url":["http://live-cdn.kksmg.com/channels/tvie/test/flv:500k"
 *         ,
 *         "http://live.gslb.letv.com/gslb?stream_id=hunanHD_1800&tag=live&ext=m3u8&sign=live_tv&platid=10&splatid=1012&temporarykey=db7c39a0ee39ab2d4d2e781d5"
 *         ,
 *         "http://pplive.shntv.cn/live/5/30/e9301e073cf94732a380b765c8b9573d.m3u8?type=ipad"
 *         ,"rtsp://rlive.tv189.cn/live/112"], "types":"2|0"
 */

public class LiveItemBean implements Parcelable {

	@Override
	public int describeContents() {
		return 0;
	}

	public LiveItemBean() {
	}

	private LiveItemBean(Parcel source) {
		readFromParcel(source);
	}

	@DatabaseField(id = true)
	private int channel_id;
	@DatabaseField
	private String channel_name;
	@DatabaseField
	private String icon_url;
	@DatabaseField
	private String province;
	@DatabaseField
	private String mode;
	@DatabaseField
	private String url;
	@DatabaseField
	private String second_urls;
	private String[] second_url;
	@DatabaseField
	private String types;

	private void readFromParcel(Parcel source) {
		channel_name = source.readString();
		icon_url = source.readString();
		province = source.readString();
		mode = source.readString();
		url = source.readString();
		second_urls = source.readString();
		second_url = (String[]) source.readArray(LiveItemBean.class
				.getClassLoader());
		types = source.readString();

	}

	@Override
	public void writeToParcel(Parcel dest, int flags) {
		dest.writeInt(channel_id);
		dest.writeString(channel_name);
		dest.writeString(icon_url);
		dest.writeString(province);
		dest.writeString(mode);
		dest.writeString(url);
		dest.writeString(second_urls);
		dest.writeArray(second_url);
		dest.writeString(types);
	}

	public static Creator CREATOR = new Creator() {

		@Override
		public LiveItemBean createFromParcel(Parcel source) {
			return new LiveItemBean(source);
		}

		@Override
		public LiveItemBean[] newArray(int size) {
			return new LiveItemBean[size];
		}
	};

	public int getChannel_id() {
		return channel_id;
	}

	public void setChannel_id(int channel_id) {
		this.channel_id = channel_id;
	}

	public String getChannel_name() {
		return channel_name;
	}

	public void setChannel_name(String channel_name) {
		this.channel_name = channel_name;
	}

	public String getIcon_url() {
		return icon_url;
	}

	public void setIcon_url(String icon_url) {
		this.icon_url = icon_url;
	}

	public String getProvince() {
		return province;
	}

	public void setProvince(String province) {
		this.province = province;
	}

	public String getMode() {
		return mode;
	}

	public void setMode(String mode) {
		this.mode = mode;
	}

	public String getUrl() {
		return url;
	}

	public void setUrl(String url) {
		this.url = url;
	}

	public String getSecond_urls() {
		return second_urls;
	}

	public void setSecond_urls(String second_urls) {
		this.second_urls = second_urls;
	}

	public String[] getSecond_url() {
		return second_url;
	}

	public void setSecond_url(String[] second_url) {
		this.second_url = second_url;
		StringBuffer buffer = new StringBuffer();
		int count = second_url.length;
		for (int i = 0; i < count; i++) {
			buffer.append(second_url[i]);
			if (i != count-1) {
				buffer.append(";");
			}
		}
		second_urls = buffer.toString();
	}

	public String getTypes() {
		return types;
	}

	public void setTypes(String types) {
		this.types = types;
	}
}

我們分析上面的代碼同時介紹一下與之相關的配置：

1、是類名，這裡我使用的數據表的名字是默認類的小寫，當然你還可以指定表名字，使用@DatabaseTable(tableName = "liveitembeans")，

2、主鍵，在上面的代碼中有一行@DatabaseField(id = true)被注解對象就是主鍵，當然我們有時候使用的一個自增長的id，我們可以設置為@DatabaseField(generatedId = true)來實現，當然還有很多其他的注解配置我這裡就不一一說明了，自己可以到官網可以查看找到自己需要的。

二、創建DBHelper

package com.jwzhangjie.capricorntv.db;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;

import com.j256.ormlite.android.apptools.OrmLiteSqliteOpenHelper;
import com.j256.ormlite.support.ConnectionSource;
import com.j256.ormlite.table.TableUtils;
import com.jwzhangjie.capricorntv.bean.LiveItemBean;

public class DBHelper extends OrmLiteSqliteOpenHelper {
	
	private static final String DATABASE_NAME = "jwzhangjie.db";
	private static final int DATABASE_VERSION = 1;

	public DBHelper(Context context){
		super(context, DATABASE_NAME, null, DATABASE_VERSION);
	}

	@Override
	public void onCreate(SQLiteDatabase sqLiteDatabase,
			ConnectionSource connectionSource) {
		try {
			TableUtils.createTable(connectionSource, LiveItemBean.class);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	@Override
	public void onUpgrade(SQLiteDatabase sqLiteDatabase,
			ConnectionSource connectionSource, int oldVer, int newVer) {
		try {
			TableUtils.dropTable(connectionSource, LiveItemBean.class, true);
			onCreate(sqLiteDatabase, connectionSource);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
}

上面使用TableUtils來創建和刪除表，還有其他的功能例如清空表內容等

三、創建操作工具

接下來就是創建一個操作數據庫的工具DAO

package com.jwzhangjie.capricorntv.uitls;

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import android.content.Context;

import com.j256.ormlite.dao.Dao;
import com.jwzhangjie.capricorntv.bean.LiveItemBean;
import com.jwzhangjie.capricorntv.db.DBHelper;

public class DBUtils {
	
	public static Dao liveDao = null;

	public DBUtils(Context context) {
		if (liveDao == null) {
			DBHelper dbHelper = new DBHelper(context);
			try {
				liveDao = dbHelper.getDao(LiveItemBean.class);
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
	}

	/**
	 * 插入直播數據,如果數據存在則進行更新
	 * 
	 * @param liveItemBean
	 */
	public void LiveCreate(LiveItemBean liveItemBean) {
		try {
			liveDao.createOrUpdate(liveItemBean);
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

	/**
	 * 連續進行插入，如果存在則更新
	 */
	public void LiveCreates(List lists) {
		try {
			for (LiveItemBean liveItemBean : lists) {
				liveDao.createOrUpdate(liveItemBean);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	/**
	 * 查詢所有的直播元素
	 * @return
	 */
	public List getLiveItemBeans(){
		List listsBeans = new ArrayList();
		try {
			listsBeans = liveDao.queryForAll();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return listsBeans;
	}

}

上面實現了創建和查詢，在上面的有一個連續插入多個數據，還可以使用OrmLite提供的批處理任務方法如下：

/**
	 * 連續進行插入，如果存在則更新
	 */
	public void LiveCreates(final List lists) {
		try {
			liveDao.callBatchTasks(new Callable() {

				@Override
				public Void call() throws Exception {
					for (LiveItemBean liveItemBean : lists) {
						liveDao.createOrUpdate(liveItemBean);
					}
					return null;
				}
			});
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

查詢除了用已有的接口，我們還可以使用sql語句來實現，比如：

// find out how many orders account-id #10 has
     GenericRawResults rawResults =
       orderDao.queryRaw(
         "select count(*) from orders where account_id = 10");
     // there should be 1 result
     List results = rawResults.getResults();
     // the results array should have 1 value
     String[] resultArray = results.get(0);
     // this should print the number of orders that have this account-id
     System.out.println("Account-id 10 has " + resultArray[0] + " orders");

四、最後釋放

當我們應用退出時候，我們需要釋放之前對象

OpenHelperManager.releaseHelper();
		dbHelper = null;