SharedPreferences - java.lang.Boolean cannot be cast to java.lang.String

Question

I'm confused with an exception that is thrown for something that shouldn't. The error is the following:

java.lang.ClassCastException: java.lang.Boolean cannot be cast to java.lang.String

But, my code doesn't try to cast a Boolean to String Ô_o Is it possible that the compiler is wrong in indicating where the exception is coming from? I'm using an Huawei

This part triggers the exception:

if(SharedPreferencesManager.getUserMRZ(ScanEUID.this).equals("0")
&& SharedPreferencesManager.getUserDocumentIdFront(ScanEUID.this) != null 
&& SharedPreferencesManager.getUserDocumentIdBack(ScanEUID.this) != null)
{

The associated methods are the following

public static String getUserMRZ(Context context){
    return getSharedPreferences(context).getString(Constants.USER_HAS_MRZ, "0");
}
public static String getUserDocumentIdFront(Context context) {
    return getSharedPreferences(context).getString(Constants.USER_DOCUMENT_ID_FRONT, null);
}
public static String getUserDocumentIdBack(Context context) {
    return getSharedPreferences(context).getString(Constants.USER_DOCUMENT_ID_BACK, null);
}

The setMRZ method

public static void setUserMRZ(Context context, String has_mrz){
        final SharedPreferences.Editor editor = getSharedPreferences(context).edit();
        editor.putString(Constants.USER_HAS_MRZ, has_mrz);
        editor.apply();
}

If there's ever been a string with that key (USER_HAS_MRZ), even if by accident, it will stay there until you clear the app's data or reinstall. Try reinstalling it to see if it still occurs. — Denny, May 10 '17 at 14:39
Check where you are first creating the USER_HAS_MRZ preference. You are probably informing a boolean value. — Jonas452, May 10 '17 at 14:41
Thank you @Jonas452 - I just updated my question to add the method that set it. So I have 3 usages and the first is : "SharedPreferencesManager.setUserMRZ(identityCheck.this, "0");" — Isabelle, May 10 '17 at 14:47

score 5 · Answer 1 · answered Aug 31 '17 at 11:11

5

Check your setters, I just had the same issue and I discovered that I'd mistakenly done a bad copy/pasta and used the Key for that value in a setter for a Boolean value...

answered Aug 31 '17 at 11:11

AZR34L

73
2
6

You saved my mental and about half of an hour of my time... Really thanks a lot. – Han Park Jan 05 '20 at 12:14
2

If the app you've installed is using a boolean preference and you now want it to be a String, you must reinstall your app. – Rafael Oct 12 '21 at 12:24

score 1 · Answer 2 · answered Feb 07 '21 at 15:18

In My case I was wrongly used the same shared preference key for different Activity, For putString and putBoolean. Though the problem arise. I used an activity as :

editor.putString("fezilalilquran", "on");

And Another Activity I used :

editor.putBoolean("fezilalilquran", true);

So, you see that, for the same key word for boolean and string in Shared Preferences, When I want to get the boolean in MainActivity, so the cast exception arise for this line :

boolean isTafseerOn = settings.getBoolean("fezilalilquran", true);

So, replacing the line in settings Activity, from :

editor.putString("fezilalilquran", "on");

to :

editor.putBoolean("fezilalilquran", true);

solved my issue:

Happy coding...... .

score 0 · Answer 3 · answered May 10 '17 at 14:49

0

Look at the documentation

https://developer.android.com/reference/android/content/SharedPreferences.html#getString(java.lang.String, java.lang.String)

If your value of Constants.USER_HAS_MRZ is Boolean, you should use getBoolean method

https://developer.android.com/reference/android/content/SharedPreferences.html#getBoolean(java.lang.String, boolean)

answered May 10 '17 at 14:49

Deni Erdyneev

1,779
18
26

2

I'm sure the OP is aware which method to use, it is described that only Strings are stored with the `setUserMRZ()` method – Denny May 10 '17 at 14:52
@Isabelle are you sure that exception had thrown in the `SharedPreferencesManager.getUserMRZ(ScanEUID.this).equals("0")` line? – Deni Erdyneev May 10 '17 at 14:55
If I refer to what the compiler mentions, yes. – Isabelle May 10 '17 at 14:58
@Isabelle did you try to run the application on another device? Show error stacktrace. – Deni Erdyneev May 10 '17 at 15:02
Doing it right now, and same error with big crash this time -_- – Isabelle May 10 '17 at 15:11
I guess thers is simple a mistake there, try to find all `Constants.USER_HAS_MRZ` usages, probably somewhere you put a boolean. And examine all preferences with https://facebook.github.io/stetho/ or Device File Explorer in AS 2.4 – Deni Erdyneev May 10 '17 at 15:17
What about the full error stacktrace, can you show that? – Denny May 11 '17 at 06:43

score 0 · Answer 4 · answered Jun 30 '22 at 15:57

0

I had this error and found that I used the same key twice (copy/paste error).

private const val PREF_IS_IMPERIAL ="imperial"
private const val PREF_LAST_CITY_SEARCH ="imperial"  //oops

answered Jun 30 '22 at 15:57

seekingStillness

4,833
5
38
68

score -3 · Answer 5 · answered May 31 '20 at 07:17

-3

In my case, I just surround the get methods with Try Catch and it works!

answered May 31 '20 at 07:17

Thiha Eung

1

It is not answering the question, instead it just tells to catch the exception. – jrh May 31 '20 at 09:55

SharedPreferences - java.lang.Boolean cannot be cast to java.lang.String

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