Java Codegen's Feign Client SimpleDateFormat is incompatible with Android

[natami]

Generating a Feign Client using Swagger Codegen v.2.2.1, results in the following exception upon including and running the Client on android with API 23.

FATAL EXCEPTION: main Process: com.brightware.iot.clients.android, PID: 1778 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.brightware.iot.clients.android/com.brightware.iot.clients.android.activities.LoginActivity_}: java.lang.IllegalArgumentException: Unknown pattern character 'X' at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) at android.app.ActivityThread.-wrap11(ActivityThread.java) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:148) at android.app.ActivityThread.main(ActivityThread.java:5417) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) Caused by: java.lang.IllegalArgumentException: Unknown pattern character 'X' at java.text.SimpleDateFormat.validatePatternCharacter(SimpleDateFormat.java:323) at java.text.SimpleDateFormat.validatePattern(SimpleDateFormat.java:312) at java.text.SimpleDateFormat.<init>(SimpleDateFormat.java:365) at java.text.SimpleDateFormat.<init>(SimpleDateFormat.java:258)

[cbornet]

Yes, see #3727. Fix is in progress.
Meanwhile, you have several solutions:

• use joda as dateLibrary
• configure the ApiClient to use Jackson's ISO8601DateFormat apiClient.getObjectMapper().setDateFormat(new ISO8601DateFormat())

[natami]

The client is using Joda as datelib.

Adding apiClient.getObjectMapper().setDateFormat(new ISO8601DateFormat()) to the mix does no difference :/

[cbornet]

Then it shouldn't try to use SimpleDateFormat... Do you have java.util.Date types somewhere in your models ?

[cbornet]

On a side note, for android, I would prefer Retrofit2. Feign is more oriented towards server/micro-service

[cbornet]

@natami can you paste the full stacktrace ? Is it crashing when instanciating the ObjectMapper ?

[cbornet]

I can't find a SimpleDateFormat with 'X' in the code we generate nor in Jackson. Are you sure it's not in your own code ?

[cbornet]

Found it in FormAwareEncoder !

[cbornet]

You can replace

this.dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSXXX");

by

this.dateFormat = new ISO8601DateFormat();

in FormAwareEncoder.
Unfortunately you have to modify the generated code for now...

[natami]

Hi, Christophe!

I'll give it a go - thanks for your time ;)