AndroidStudio 优秀的第三方数据库 GreenDao

原文：http://blog.csdn.net/ldld1717/article/details/72818917

greenDAO是一款面向Android的轻便快捷的ORM，可将对象映射到SQLite数据库。 针对android进行了高度优化，greenDAO提供了出色的性能并消耗了最少的内存。

    GitHub地址：点击打开链接

    GreenDao的优点如下：

    应用广泛：greenDAO自2011年以来一直在使用，被无数着名的应用程序所使用
    超简单：简洁直观的API，在V3中带有注释
    小：小于150K，它只是纯Java jar（没有CPU依赖的本机部分）
    快速：可能是由智能代码生成驱动的Android中最快的ORM
    安全和表达性的查询API：QueryBuilder使用属性常量来避免打字错误
    强大的连接：跨实体查询，甚至连接连接以进行复杂关系
    灵活的属性类型：使用自定义类或枚举来表示实体中的数据
    加密：支持SQLCipher加密数据库

一.使用准备

    1.在build.gradle(Module:app)中加入

    

compile 'org.greenrobot:greendao:3.0.1'
compile 'org.greenrobot:greendao-generator:3.0.0'

    2.在build.gradle(Module:app)中引入插件并自定义路径

apply plugin: 'org.greenrobot.greendao'

greendao {
    schemaVersion 1
    daoPackage 'com.example.leidong.greendaotest.gen'
    targetGenDir 'src/main/java'
}

    3.在build.gradle(Project:XXX)的dependencies中加入
   

classpath 'org.greenrobot:greendao-gradle-plugin:3.0.0'

       

    4.创建一个User的Bean

    

 package com.example.leidong.greendaotest.beans;

 import org.greenrobot.greendao.annotation.Entity;

 import org.greenrobot.greendao.annotation.Id;

 import org.greenrobot.greendao.annotation.Generated;

 /**
  * Created by leidong on 2017/5/30
  */
 @Entity
 public class User {

     @Id(autoincrement = true)

     private Long id;

     private String name;

     private int age;

     public int getAge() {

         return this.age;
     }

     public void setAge(int age) {

         this.age = age;
     }

     public String getName() {

         return this.name;
     }
     public void setName(String name) {

         this.name = name;
     }

     public Long getId() {

         return this.id;
     }
     public void setId(Long id) {

         this.id = id;
     }

     @Generated(hash = 1309193360)

     public User(Long id, String name, int age) {

         this.id = id;

         this.name = name;

         this.age = age;
     }

     @Generated(hash = 586692638)

     public User() {

     }

 }

    5.编译项目，生成新的文件，结构如下

   
    

二.GreenDao的简单使用

    1.新建一个MyApplication类继承自MyApplication。

    

 package com.example.leidong.greendaotest;

 import android.app.Application;

 import android.database.sqlite.SQLiteDatabase;

 import com.example.leidong.greendaotest.gen.DaoMaster;

 import com.example.leidong.greendaotest.gen.DaoSession;

 /**
  * Created by leidong on 2017/5/30
  */

 public class MyApplication extends Application {

     private DaoMaster.DevOpenHelper mHelper;

     private SQLiteDatabase db;

     private DaoMaster mDaoMaster;

     private DaoSession mDaoSession;

     public static MyApplication instances;

     @Override
     public void onCreate() {

         super.onCreate();

         instances = this;

         setDatabase();
     }

     public static MyApplication getInstances(){

         return instances;
     }

     /**
      * 设置greenDao
      */
     private void setDatabase() {

         mHelper = new DaoMaster.DevOpenHelper(this, "leidong.db", null);

         db = mHelper.getWritableDatabase();

数据库连接。   

         mDaoMaster = new DaoMaster(db);

         mDaoSession = mDaoMaster.newSession();
     }

     public DaoSession getDaoSession() {

         return mDaoSession;
     }

     public SQLiteDatabase getDb() {

         return db;
     }
 }

在AndroidManifest.xml的application中写入：

android:name=".MyApplication"

2.MainActivity,Java

 package com.example.leidong.greendaotest;

 import android.os.Bundle;

 import android.support.v7.app.AppCompatActivity;

 import android.view.View;

 import android.widget.Button;

 import android.widget.EditText;

 import android.widget.TextView;

 import com.example.leidong.greendaotest.beans.User;

 import com.example.leidong.greendaotest.gen.UserDao;

 import java.util.List;

 public class MainActivity extends AppCompatActivity implements View

 .OnClickListener {

     private UserDao userDao;

     private EditText editText1, editText2, editText3;

     private TextView textView;

     private Button button1, button2, button3, button4;

     @Override

     protected void onCreate(Bundle savedInstanceState) {

         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);

         initWidgets();

         initActions();
     }

     /**
      * 获取组件
      */
     private void initWidgets() {

         editText1 = (EditText) findViewById(R.id.editText1);

         editText2 = (EditText) findViewById(R.id.editText2);

         editText3 = (EditText) findViewById(R.id.editText3);

         textView = (TextView) findViewById(R.id.textView);

         button1 = (Button) findViewById(R.id.button1);

         button2 = (Button) findViewById(R.id.button2);

         button3 = (Button) findViewById(R.id.button3);

         button4 = (Button) findViewById(R.id.button4);
     }

     /**
      * 初始化动作
      */
     private void initActions() {

         button1.setOnClickListener(this);

         button2.setOnClickListener(this);

         button3.setOnClickListener(this);

         button4.setOnClickListener(this);
     }

     /**
      * 按钮点击事件
      * @param v 视图
      */
     @Override
     public void onClick(View v) {

         switch (v.getId()){

             case R.id.button1:

                 addUser();

                 break;
             case R.id.button2:

                 deleteUser();

                 break;

             case R.id.button3:

                 modifyUser();

                 break;

             case R.id.button4:

                 queryUser();

                 break;

             default:
                 break;
         }
     }

     /**
      * 查
      */
     private void queryUser() {

         StringBuilder sb = new StringBuilder();

         userDao = MyApplication.getInstances().getDaoSession().getUserDao();

         List userList = userDao.loadAll();

         for(int i = 0; i < userList.size(); i++){

             String temp = "";

             temp += "ID = " + userList.get(i).getId() + " ";

             temp += "Name = " + userList.get(i).getName() + " ";

             temp += "Age = " + userList.get(i).getAge() + "\n";

             sb.append(temp);
         }

         textView.setText(sb.toString());
     }

     /**
      * 改
      */
     private void modifyUser() {

         long id = Long.parseLong(editText1.getText().toString().trim());

         String name = editText2.getText().toString().trim();

         int age = Integer.parseInt(editText3.getText().toString().trim());

         userDao = MyApplication.getInstances().getDaoSession().getUserDao();

         User user = new User();

         user.setId(id);

         user.setName(name);

         user.setAge(age);

         userDao.update(user);
     }

     /**
      * 删
      */
     private void deleteUser() {
         long id = Long.parseLong(editText1.getText().toString().trim());

         userDao = MyApplication.getInstances().getDaoSession().getUserDao();

         userDao.deleteByKey(id);
     }

     /**
      * 增
      */
     private void addUser() {

         String name = editText2.getText().toString().trim();

         int age = Integer.parseInt(editText3.getText().toString().trim());


         userDao = MyApplication.getInstances().getDaoSession().getUserDao();

         User user = new User();

         user.setName(name);

         user.setAge(age);

         userDao.insert(user);
     }
 }

3.activity_main.xml

 xml version="1.0" encoding="utf-8"?>

 <RelativeLayout

     xmlns:android="http://schemas.android.com/apk/res/android"

     xmlns:tools="http://schemas.android.com/tools"

     android:layout_width="match_parent"

     android:layout_height="match_parent"

     android:layout_margin="16dp"

     tools:context="com.example.leidong.greendaotest.MainActivity">

     <android.support.design.widget.TextInputLayout

         android:layout_width="match_parent"

         android:layout_height="wrap_content"

         android:layout_alignParentTop="true"

         android:layout_alignParentLeft="true"

         android:layout_alignParentStart="true"

         android:id="@+id/textInputLayout">

         <EditText
             android:id="@+id/editText1"

             android:layout_width="match_parent"

             android:layout_height="wrap_content"

             android:hint="ID" />
     android.support.design.widget.TextInputLayout>

     <android.support.design.widget.TextInputLayout

         android:layout_width="match_parent"

         android:layout_height="wrap_content"

         android:layout_below="@+id/textInputLayout"

         android:layout_centerHorizontal="true"

         android:layout_marginTop="16dp"

         android:id="@+id/textInputLayout2">

         <EditText
             android:id="@+id/editText2"

             android:layout_width="match_parent"

             android:layout_height="wrap_content"

             android:hint="Name" />

     android.support.design.widget.TextInputLayout>

     <android.support.design.widget.TextInputLayout

         android:layout_width="match_parent"

         android:layout_height="wrap_content"

         android:layout_below="@+id/textInputLayout2"

         android:layout_centerHorizontal="true"

         android:layout_marginTop="16dp"

         android:id="@+id/textInputLayout3">

         <EditText
             android:id="@+id/editText3"

             android:layout_width="match_parent"

             android:layout_height="wrap_content"

             android:hint="Age" />
     android.support.design.widget.TextInputLayout>


     <TextView

         android:id="@+id/textView"

         android:background="@drawable/fillet"

         android:textSize="16sp"

         android:textColor="#ffffff"

         android:padding="16dp"

         android:layout_width="wrap_content"

         android:layout_height="wrap_content"

         android:layout_alignParentEnd="true"

         android:layout_alignParentLeft="true"

         android:layout_alignParentRight="true"

         android:layout_alignParentStart="true"

         android:layout_below="@+id/textInputLayout3"

         android:layout_above="@+id/linearLayout" />

     <LinearLayout

         android:layout_width="match_parent"

         android:layout_height="wrap_content"

         android:layout_alignParentBottom="true"

         android:layout_alignParentLeft="true"

         android:layout_alignParentStart="true"

         android:orientation="horizontal"

         android:weightSum="4"

         android:layout_marginTop="8dp"

         android:id="@+id/linearLayout">
         <Button
             android:id="@+id/button1"

             android:layout_margin="1dp"

             android:layout_weight="1"

             android:layout_width="match_parent"

             android:layout_height="36dp"

             android:text="Add"

             android:textAllCaps="false"

             android:background="@drawable/fillet"/>

         <Button
             android:id="@+id/button2"

             android:layout_margin="1dp"

             android:layout_weight="1"

             android:layout_width="match_parent"

             android:layout_height="36dp"

             android:text="Delete"

             android:textAllCaps="false"

             android:background="@drawable/fillet"/>

         <Button
             android:id="@+id/button3"

             android:layout_margin="1dp"

             android:layout_weight="1"

             android:layout_width="match_parent"

             android:layout_height="36dp"

             android:text="Modify"

             android:textAllCaps="false"

             android:background="@drawable/fillet"/>

         <Button
             android:id="@+id/button4"

             android:layout_margin="1dp"

             android:layout_weight="1"

             android:layout_width="match_parent"

             android:layout_height="36dp"

             android:text="Query"

             android:textAllCaps="false"

             android:background="@drawable/fillet"/>
     LinearLayout>

 RelativeLayout>

其中需要在build.gradle中引入：

compile 'com.android.support:design:23.4.0'

三.运行结果

工程下载：https://github.com/leidongld/GreenDaoTest