SqlGenerator
APP比较简单或者APP数据库操作比较少, 简单的几张表, 少量的数据存储。 这个时候其实没有必要去使用第三方的ORM库
- 需要去学习第三方ORM库, 增加学习成本, 也会一定程度上增加APP的复杂度
- 如果使用或者选择不当的话, 可能影响APP整体的性能, 好多ORM库其实是用运行时注解和反射来实现的, 对性能会有一定的影响
SqlGenerator致力于在不使用ORM库的情况下, 通过生成一些boilerplate code方式简化数据库操作, 从而减轻工作量
现在SqlGenerator已经支持根据Model的定义自动生成相应的Table定义, 避免编写枯燥的代码
- 根据Model的属性名生成Table的列名, 并且可以配置列的约束
- 根据Model的定义生成建表SQL, 支持外键
- 生成建索引SQL
- 支持复杂类型的映射
Model定义如下
@Table(name = "User")
@Index(name = "name_age_index", columns = {"name", "age"}, unique = true)
public class User {
@PrimaryKey
public long id;
@Column(unique = true, notNULL = true)
public String name;
@Serializer(
serializedTypeCanonicalName = String.class,
serializerCanonicalName = FileSerializer.class)
public File avtar;
@Column(check = "age>16")
public int age;
@Column(name = "address_id")
public Address address;
@ForeignKey(referenceTableName = "Group", referenceColumnName = "id", action = "ON UPDATE CASCADE")
public long groupId;
}
最终会生成表的外观类
public final class UserContract {
public static final String TABLE_NAME = "User";
public static final String ID_COLUMN = "id";
public static final String NAME_COLUMN = "name";
public static final String AVTAR_COLUMN = "avtar";
public static final String AGE_COLUMN = "age";
public static final String ADDRESS_ID_COLUMN = "address_id";
public static final String GROUPID_COLUMN = "groupId";
public static final String CREATE_TABLE_SQL = "CREATE TABLE IF NOT EXISTS User(id INTEGER PRIMARY KEY AUTOINCREMENT,name TEXT NOT NULL UNIQUE,avtar TEXT,age INTEGER CHECK(age>16),address_id TEXT,groupId INTEGER,FOREIGN KEY(groupId) REFERENCES Group(id) ON UPDATE CASCADE)";
public static final String CREATE_NAME_AGE_INDEX_SQL = "CREATE INDEX name_age_index ON User(name,age)";
public UserContract() {
}
public static void createTable(SQLiteDatabase db) {
db.execSQL("CREATE TABLE IF NOT EXISTS User(id INTEGER PRIMARY KEY AUTOINCREMENT,name TEXT NOT NULL UNIQUE,avtar TEXT,age INTEGER CHECK(age>16),address_id TEXT,groupId INTEGER,FOREIGN KEY(groupId) REFERENCES Group(id) ON UPDATE CASCADE)");
}
public static void createIndex(SQLiteDatabase db) {
db.execSQL("CREATE INDEX name_age_index ON User(name,age)");
}
public static void dropTable(SQLiteDatabase db) {
db.execSQL("DROP TABLE IF EXISTS User");
}
}
Download
buildscript {
repositories {
mavenCentral()
}
dependencies {
classpath 'com.neenbedankt.gradle.plugins:android-apt:1.8'
}
}
apply plugin: 'com.neenbedankt.android-apt'
dependencies {
compile 'com.github.tubb.sqlgenerator:sqlgenerator-annotations:0.0.3-SNAPSHOT'
apt 'com.github.tubb.sqlgenerator:sqlgenerator-compiler:0.0.3-SNAPSHOT'
}
Usage
定义好Model类之后重新构建应用, 会生成以ModelNameContract命名的表外观类, 可以在moduleName/build/intermediates/classes目录下查看
./gradlew clean build
Note
SqlGenerator还处于开发阶段, 功能不是很稳定, 正式项目请谨慎使用。非常希望有兴趣的朋友来一起完善这个library
