android - ORMLite 错误 : No fields have a DatabaseField annotation in class java. lang.Character

Question

我使用 4.46 版本的核心 ORMLite 和 Android，我一直有这个问题。

Foo 类

@DatabaseTable
public class Foo {

    @DatabaseField(generatedId = true)
    public int id;
    @DatabaseField(index = true)
    public String title;
    @ForeignCollectionField
    ForeignCollection<Foo2> foo2s;

    public Foo() {
        // needed by ormlite
    }

}

Foo2 类

@DatabaseTable
public class Foo2 {

    @DatabaseField(generatedId = true)
    public int id;
    @DatabaseField
    public Date date;

    public Foo2() {
        // needed by ormlite
    }
}

ORMLiteFragment(我需要从 Fragment 调用 getHelper())

public class OrmLiteFragment extends Fragment {

    private DatabaseHelper databaseHelper = null;

    protected DatabaseHelper getHelper() {
        if (databaseHelper == null) {
            databaseHelper =
                OpenHelperManager.getHelper(getActivity(), DatabaseHelper.class);
        }
        return databaseHelper;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (databaseHelper != null) {
            OpenHelperManager.releaseHelper();
            databaseHelper = null;
        }
    }
}

Activity

public class MainActivity extends FragmentActivity {
    /**
    * Some methods non important for this...
    */

    public static class SectionFragment extends OrmLiteFragment { 
        @Override
        public View onCreateView(LayoutInflater inflater,
                ViewGroup container, Bundle savedInstanceState) {

            // Some code....

            getHelper().getFoo2RuntimeDao(); // HERE FIRES THE ERROR!

            // Some code....
        }
    }
}

DatabaseHelper 类与Android examples code page 相同但是使用 Foo2RuntimeDao() 和 Foo1RuntimeDao()

问题

09-03 14:27:15.756: E/AndroidRuntime(557): FATAL EXCEPTION: main
09-03 14:27:15.756: E/AndroidRuntime(557): java.lang.IllegalArgumentException: No fields have a DatabaseField annotation in class java.lang.Character
09-03 14:27:15.756: E/AndroidRuntime(557):  at com.j256.ormlite.table.DatabaseTableConfig.extractFieldTypes(DatabaseTableConfig.java:215)
09-03 14:27:15.756: E/AndroidRuntime(557):  at com.j256.ormlite.table.DatabaseTableConfig.fromClass(DatabaseTableConfig.java:146)
09-03 14:27:15.756: E/AndroidRuntime(557):  at com.j256.ormlite.table.TableInfo.<init>(TableInfo.java:53)
09-03 14:27:15.756: E/AndroidRuntime(557):  at com.j256.ormlite.dao.BaseDaoImpl.initialize(BaseDaoImpl.java:149)
09-03 14:27:15.756: E/AndroidRuntime(557):  at com.j256.ormlite.dao.BaseDaoImpl.<init>(BaseDaoImpl.java:126)

- 更新 1

如果我尝试得到 queryForAll() (返回一个列表)并且我之前没有保存数据我得到一个 NullPointerException 而不是一个空列表或 null。像这样:

public class MainActivity2 extends OrmLiteBaseActivity<DatabaseHelper> {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        getHelper().getChapterRunDao();   //This Works!
        getHelper().getChapterRunDao().queryForAll();  //This throws NullPointerException
    }
}

问题

09-04 15:32:13.261: E/AndroidRuntime(3615): FATAL EXCEPTION: main
09-04 15:32:13.261: E/AndroidRuntime(3615): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.emanga/com.emanga.ORMLite}: java.lang.NullPointerException
09-04 15:32:13.261: E/AndroidRuntime(3615):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
09-04 15:32:13.261: E/AndroidRuntime(3615):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)

Answer 1

如果您没有字段错误，这将有所帮助
我在这里的回答:ORMLite error no databasefield annotations exists
给出解决方案可能已经晚了，但这是我的解决方案:
你看到混淆器试图混淆代码，如果你深入阅读混淆器或介绍

http://proguard.sourceforge.net/FAQ.html

what Shrinking in proguard -> ProGuard之类的Shrinking程序可以分析字节码，移除不用的类、字段和方法。所以从这里我们可以假设它正在删除你的对象，因为它没有被任何地方使用......
所以你可能需要？您需要阻止混淆器从进程中逃避该方法或对象所以这是该行..:
-keep class com.j256.**<br>
-keepclassmembers class com.j256.** { *; }<br>
-keep enum com.j256.**<br>
-keepclassmembers enum com.j256.** { *; }<br>
-keep interface com.j256.**<br>
-keepclassmembers interface com.j256.** { *; }

这一行将阻止混淆器删除我的公共(public)方法和变量..

-keepclassmembers class classpath.** {
public *;
}
你需要为atlest id写列名...因为它会搜索它并且proguard会改变它的名字...所以你需要为主键定义列名id..