使用步骤
第一步：在app的Build.gradle中添加如下配置：
apply plugin: 'org.greenrobot.greendao'
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
greendao{
schemaVersion 1
daoPackage 'com.admom.mygreendaotest'
targetGenDir 'src/main/java'
}
//schemaVersion： 数据库schema版本，也可以理解为数据库版本号
//daoPackage：设置DaoMaster、DaoSession、Dao包名
//targetGenDir：设置DaoMaster、DaoSession、Dao目录
//targetGenDirTest：设置生成单元测试目录
//generateTests：设置自动生成单元测试用例
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile 'com.android.support:appcompat-v7:24.2.1'
testCompile 'junit:junit:4.12'
compile 'org.greenrobot:greendao:3.2.0'
}
在工程的Build.gradle中添加如下配置：
buildscript {
repositories {
jcenter()
mavenCentral()
}
dependencies {
classpath 'com.android.tools.build:gradle:2.2.0'
classpath 'org.greenrobot:greendao-gradle-plugin:3.2.0'
}
}
写实体类
@Entity
public class User {
@Id(autoincrement = true)
private Long id;
private String name;
private int age;
private boolean isBoy;
}
点击Build后make project后GreenDao会自动帮你生成get/set方法如下:
@Entity
public class User {
@Id(autoincrement = true)
private Long id;
private String name;
private int age;
private boolean isBoy;
@Generated(hash = 1724489812)
public User(Long id, String name, int age, boolean isBoy) {
this.id = id;
this.name = name;
this.age = age;
this.isBoy = isBoy;
}
@Generated(hash = 586692638)
public User() {
}
public Long getId() {
return this.id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return this.age;
}
public void setAge(int age) {
this.age = age;
}
public boolean getIsBoy() {
return this.isBoy;
}
public void setIsBoy(boolean isBoy) {
this.isBoy = isBoy;
}
}
接下来就是封装
GreenDaoManager
这个自己的工具类调用方法：设置为单例模式，方便后续操作
public class GreenDaoManager {
private DaoMaster mDaoMaster;
private DaoSession mDaoSession;
private static GreenDaoManager mInstance; //单例
private GreenDaoManager(){
if (mInstance == null) {
DaoMaster.DevOpenHelper devOpenHelper = new
DaoMaster.DevOpenHelper(MyApplication.getContext(), "user1-db", null);//此处为自己需要处理的表
mDaoMaster = new DaoMaster(devOpenHelper.getWritableDatabase());
mDaoSession = mDaoMaster.newSession();
}
}
public static GreenDaoManager getInstance() {
if (mInstance == null) {
synchronized (GreenDaoManager.class) {//保证异步处理安全操作
if (mInstance == null) {
mInstance = new GreenDaoManager();
}
}
}
return mInstance;
}
public DaoMaster getMaster() {
return mDaoMaster;
}
public DaoSession getSession() {
return mDaoSession;
}
public DaoSession getNewSession() {
mDaoSession = mDaoMaster.newSession();
return mDaoSession;
}
}
在Application中配置好：
public class MyApplication extends Application {
private static Context mContext;
@Override
public void onCreate() {
super.onCreate();
mContext = getApplicationContext();
//greenDao全局配置,只希望有一个数据库操作对象
GreenDaoManager.getInstance();
}
public static Context getContext() {
return mContext;
}
}
这时就可以在自己的代码中进行使用了，我将GreenDao一些常用方法置下：
public class MainActivity extends AppCompatActivity {
//@Transient，该注解表示这个属性将不会作为数据表中的一个字段
//@NotNull表示该字段不可以为空，@Unique表示该字段唯一
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// updatadata();
// insertdata();
// querydata();
//删除数据
// getUserDao().deleteByKey(2l);//long类型
// querydata();
// querydataBy();
getuserById();
}
private void getuserById() {
User user =getUserDao().load(1l);
Log.i("tag", "结果：" + user.getId() + "," + user.getName() + "," + user.getAge() + "," + user.getIsBoy() + ";");
}
private void insertdata() {
//插入数据
User insertData = new User(null, "插入数据", 24, false);
getUserDao().insert(insertData);
}
private void updatadata() {
//更改数据
List<User> userss = getUserDao().loadAll();
User user = new User(userss.get(0).getId(), "更改后的数据用户", 22, true);
getUserDao().update(user);
}
private void querydata() {
//查询数据详细
List<User> users = getUserDao().loadAll();
Log.i("tag", "当前数量：" + users.size());
for (int i = 0; i < users.size(); i++) {
Log.i("tag", "结果：" + users.get(i).getId() + "," + users.get(i).getName() + "," + users.get(i).getAge() + "," + users.get(i).getIsBoy() + ";");
}
}
private void querydataBy() {查询条件
Query<User> nQuery = getUserDao().queryBuilder()
// .where(UserDao.Properties.Name.eq("user1"))//.where(UserDao.Properties.Id.notEq(999))
.orderAsc(UserDao.Properties.Age)//.limit(5)//orderDesc
.build();
List<User> users = nQuery.list();
Log.i("tag", "当前数量：" + users.size());
for (int i = 0; i < users.size(); i++) {
Log.i("tag", "结果：" + users.get(i).getId() + "," + users.get(i).getName() + "," + users.get(i).getAge() + "," + users.get(i).getIsBoy() + ";");
}
// QueryBuilder qb = userDao.queryBuilder();
// qb.where(Properties.FirstName.eq("Joe"),
// qb.or(Properties.YearOfBirth.gt(1970),
// qb.and(Properties.YearOfBirth.eq(1970), Properties.MonthOfBirth.ge(10))));
// List youngJoes = qb.list();
}
/**
* 根据查询条件,返回数据列表
* @param where 条件
* @param params 参数
* @return 数据列表
*/
public List<User> queryN(String where, String... params){
return getUserDao().queryRaw(where, params);
}
/**
* 根据用户信息,插件或修改信息
* @param user 用户信息
* @return 插件或修改的用户id
*/
public long saveN(User user){
return getUserDao().insertOrReplace(user);
}
/**
* 批量插入或修改用户信息
* @param list 用户信息列表
*/
public void saveNLists(final List<User> list){
if(list == null || list.isEmpty()){
return;
}
getUserDao().getSession().runInTx(new Runnable() {
@Override
public void run() {
for(int i=0; i<list.size(); i++){
User user = list.get(i);
getUserDao().insertOrReplace(user);
}
}
});
}
/**
* 删除所有数据
*/
public void deleteAllNote(){
getUserDao().deleteAll();
}
/**
* 根据用户类,删除信息
* @param user 用户信息类
*/
public void deleteNote(User user){
getUserDao().delete(user);
}
private UserDao getUserDao() {
return GreenDaoManager.getInstance().getSession().getUserDao();
}
}
一般的简单数据库升级，如下操作即可：
1 首先在module的gradle文件中修改版本号：
greendao{
schemaVersion 5
daoPackage 'xxxxxxxxxx'
targetGenDir 'src/main/java'
}
2 修改实体类为自己需要的类型，重现编译项目运行即可。
这样修改，之前的数据库会被删除，重新创建。
下面为一些常用的注解使用方式：
@Entity
public class User {
@Id (autoincrement = true )
private Long id;
@Property (nameInDb = "USERNAME" )
private String name;
@NotNull
private int repos;
@Transient
private int tempUsageCount;
...
}
@Entity 用于标识这是一个需要Greendao帮我们生成代码的bean
@Id 标明主键，括号里可以指定是否自增
@Property 用于设置属性在数据库中的列名（默认不写就是保持一致）
@NotNull 非空
@Transient 标识这个字段是自定义的不会创建到数据库表里
@Unique 添加唯一约束
关系注解：
@Entity
public class Order {
@Id private Long id;
private long customerId;
@ToOne (joinProperty = "customerId" )
private Customer customer;
}
@Entity
public class Customer {
@Id private Long id;
}
@ToOne 是将自己的一个属性与另一个表建立关联
@Entity
public class User {
@Id private Long id;
@ToMany (referencedJoinProperty = "ownerId" )
private List<Site> ownedSites;
}
@Entity
public class Site {
@Id private Long id;
private long ownerId;
}
// ----------------------------
@Entity
public class User {
@Id private Long id;
@Unique private String authorTag;
@ToMany (joinProperties = {
@JoinProperty (name = "authorTag" , referencedName = "ownerTag" )
})
private List<Site> ownedSites;
}
@Entity
public class Site {
@Id private Long id;
@NotNull private String ownerTag;
}
@ToMany的属性referencedJoinProperty，类似于外键约束。
@JoinProperty 对于更复杂的关系，可以使用这个注解标明目标属性的源属性。