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