我正在尝试使用谷歌的Android体系结构组件中的新Room ORM,但我遵循了文档,但是当我运行代码时,我得到java.lang.RuntimeException: cannot find implementation for com.zeyad.usecases.app.UserDatabase. UserDatabase_Impl does not exist
这是我的代码:
Gradle项目:
allprojects {
repositories {
jcenter()
maven { url 'https://jitpack.io' }
maven { url 'https://maven.google.com' }
}
}
摇篮模块:
compile "android.arch.lifecycle:runtime:1.0.0-alpha1"
compile "android.arch.lifecycle:extensions:1.0.0-alpha1"
annotationProcessor "android.arch.lifecycle:compiler:1.0.0-alpha1"
compile "android.arch.persistence.room:runtime:1.0.0-alpha1"
annotationProcessor "android.arch.persistence.room:compiler:1.0.0-alpha1"
用户:
@Entity(tableName = "User")
public class User {
static final String LOGIN = "login";
private static final String ID = "id", AVATAR_URL = "avatar_url";
@PrimaryKey
@SerializedName(LOGIN)
@ColumnInfo(name = LOGIN)
String login;
@SerializedName(ID)
@ColumnInfo(name = ID)
int id;
@SerializedName(AVATAR_URL)
@ColumnInfo(name = AVATAR_URL)
String avatarUrl;
public User() {
}
public User(String login, int id, String avatarUrl) {
this.login = login;
this.id = id;
this.avatarUrl = avatarUrl;
}
public static boolean isEmpty(User user) {
return user == null || (user.login == null && user.avatarUrl == null);
}
public String getLogin() {
return login;
}
public void setLogin(String login) {
this.login = login;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getAvatarUrl() {
return avatarUrl;
}
public void setAvatarUrl(String avatarUrl) {
this.avatarUrl = avatarUrl;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
User user = (User) o;
return id == user.id && (login != null ? login.equals(user.login) : user.login == null
&& (avatarUrl != null ? avatarUrl.equals(user.avatarUrl) : user.avatarUrl == null));
}
@Override
public int hashCode() {
int result = login != null ? login.hashCode() : 0;
result = 31 * result + id;
result = 31 * result + (avatarUrl != null ? avatarUrl.hashCode() : 0);
return result;
}
}
UserDatabase:
@Database(entities = {User.class}, version = 1)
public abstract class UserDatabase extends RoomDatabase {
public abstract RoomBaseDao roomBaseDao();
}
RoomBaseDao:
@Dao
public interface RoomBaseDao {
@Insert(onConflict = OnConflictStrategy.REPLACE)
void insertItemsReplace(User... objects);
@Update(onConflict = OnConflictStrategy.REPLACE)
void updateItemsReplace(User... objects);
@Delete
void deleteItem(User object);
}
应用程序onCreate:
UserDatabase gDb = Room.databaseBuilder(this, UserDatabase.class, "test-db").build(); // throws the exception above
提前致谢。
最佳答案
就我而言,我使用的是旧版本的 ButterKnife ,该版本需要android-apt
插件。因此,我更新了 ButterKnife (现在使用注释处理器),并删除了 Gradle 文件中的插件声明。
可能这不是您的问题,但这也许会帮助其他人。