GreenDao使用中遇到的异常

类型 Character 无法直接存储到数据库

Character 类型不是原始支持的类型, 转换为 String 类型存储到数据库;

    private String firstCharString = "~";
    @Transient
    private Character firstChar = '~';//放弃存储

    public void setFirstCharString(String firstCharString) {
        // 在 set String 时, 给 Character 赋值
        if (firstCharString.length() > 0) {
            firstChar = firstCharString.charAt(0);
        } else {
            firstChar = BTConfig.specialChar;
        }
        this.firstCharString = firstCharString;
    }
    
     public void setFirstChar(Character firstChar) {
        firstCharString = firstChar + "";
        this.firstChar = firstChar;
    }

private String firstCharString = "~";

@Transient

private Character firstChar = '~';//放弃存储

public void setFirstCharString(String firstCharString) {

// 在 set String 时, 给 Character 赋值

if (firstCharString.length() > 0) {

firstChar = firstCharString.charAt(0);

} else {

firstChar = BTConfig.specialChar;

}

this.firstCharString = firstCharString;

}

public void setFirstChar(Character firstChar) {

firstCharString = firstChar + "";

this.firstChar = firstChar;

}

构造方法发生改变

Error:Execution failed for task ':../libs:lib:greendao'.
> Constructor (see ....) has been changed after generation.
  Please either mark it with @Keep annotation instead of @Generated to keep it untouched,
  or use @Generated (without hash) to allow to replace it.

Error:Execution failed for task ':../libs:lib:greendao'.

> Constructor (see ....) has been changed after generation.

Please either mark it with @Keep annotation instead of @Generated to keep it untouched,

or use @Generated (without hash) to allow to replace it.

删掉自动生成的构造方法, 然后再次编译重新生成构造方法

NullPointerException getDatabaseLocked

DevOpenHelper(Context context, String name, CursorFactory factory) 构造参数传入的 Context 对象为 null, 使用其它 Context 作为参数

 
java.lang.NullPointerException
    at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:224)
    at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:164)
     at org.greenrobot.greendao.database.DatabaseOpenHelper.getWritableDb(DatabaseOpenHelper.java:59)
     ......
     ......
     at android.view.View.performClick(View.java:4438)
     at android.view.View$PerformClick.run(View.java:18422)
     at android.os.Handler.handleCallback(Handler.java:733)
     at android.os.Handler.dispatchMessage(Handler.java:95)
     at android.os.Looper.loop(Looper.java:136)
     at android.app.ActivityThread.main(ActivityThread.java:5001)
     at java.lang.reflect.Method.invokeNative(Native Method)
     at java.lang.reflect.Method.invoke(Method.java:515)
     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:797)
     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:613)
    at dalvik.system.NativeStart.main(Native Method)

java.lang.NullPointerException

at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:224)

at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:164)

at org.greenrobot.greendao.database.DatabaseOpenHelper.getWritableDb(DatabaseOpenHelper.java:59)

......

at android.view.View.performClick(View.java:4438)

at android.view.View$PerformClick.run(View.java:18422)

at android.os.Handler.handleCallback(Handler.java:733)

at android.os.Handler.dispatchMessage(Handler.java:95)

at android.os.Looper.loop(Looper.java:136)

at android.app.ActivityThread.main(ActivityThread.java:5001)

at java.lang.reflect.Method.invokeNative(Native Method)

at java.lang.reflect.Method.invoke(Method.java:515)

at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:797)

at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:613)

at dalvik.system.NativeStart.main(Native Method)

冷水