Gracefully handle nulls in JSON translation file

[pindab0ter]

Additional information

We are in the midst of translating our Laravel application and as such, some entries still have null as its value. The plugin therefore fails to load the translation files.

Instead of crashing, it should ignore any null values and display some text that denotes the key doesn't have a translation yet.

E.g.:

lang/en.json

{
  "some_key": "Some Key",
  "some_untranslated_key": null
}

Exception trace

An error occurred while processing translation files.
Config: SINGLE => JSON (*.json)
Path: <path_to_project>/lang
Please check examples at https://github.com/marhali/easy-i18n before reporting an issue!

java.io.IOException: TranslationFile{virtualFile=file:///Users/hans/Developer/school-portal/portalxm/lang/en.json, locale='en', namespace='null'}

JsonNull
	at de.marhali.easyi18n.io.IOHandler.read(IOHandler.java:83)
	at de.marhali.easyi18n.DataStore.lambda$loadFromPersistenceLayer$0(DataStore.java:54)
	at com.intellij.openapi.application.impl.AnyThreadWriteThreadingSupport.runReadAction$lambda$3(AnyThreadWriteThreadingSupport.kt:258)
	at com.intellij.openapi.application.impl.AnyThreadWriteThreadingSupport.runReadAction(AnyThreadWriteThreadingSupport.kt:272)
	at com.intellij.openapi.application.impl.AnyThreadWriteThreadingSupport.runReadAction(AnyThreadWriteThreadingSupport.kt:258)
	at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:853)
	at de.marhali.easyi18n.DataStore.loadFromPersistenceLayer(DataStore.java:52)
	at de.marhali.easyi18n.InstanceManager.reload(InstanceManager.java:75)
	at de.marhali.easyi18n.action.ReloadAction.actionPerformed(ReloadAction.java:27)
	at com.intellij.openapi.actionSystem.impl.ActionButton.actionPerformed(ActionButton.java:223)
	at com.intellij.openapi.actionSystem.impl.ActionButton.lambda$performAction$2(ActionButton.java:203)
	at com.intellij.openapi.actionSystem.impl.ActionManagerImpl.performWithActionCallbacks(ActionManagerImpl.kt:1173)
	at com.intellij.openapi.actionSystem.ex.ActionUtil.performDumbAwareWithCallbacks(ActionUtil.kt:396)
	at com.intellij.openapi.actionSystem.impl.ActionButton.performAction(ActionButton.java:203)
	at com.intellij.openapi.actionSystem.impl.ActionButton.processMouseEvent(ActionButton.java:519)
	at java.desktop/java.awt.Component.processEvent(Component.java:6427)
	at java.desktop/java.awt.Container.processEvent(Container.java:2266)
	at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:5032)
	at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2324)
	at java.desktop/java.awt.Component.dispatchEvent(Component.java:4860)
	at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4963)
	at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Container.java:4577)
	at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Container.java:4518)
	at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2310)
	at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2810)
	at java.desktop/java.awt.Component.dispatchEvent(Component.java:4860)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:783)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:728)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:722)
	at java.base/java.security.AccessController.doPrivileged(AccessController.java:400)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:98)
	at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:755)
	at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:753)
	at java.base/java.security.AccessController.doPrivileged(AccessController.java:400)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87)
	at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:752)
	at com.intellij.ide.IdeEventQueue.defaultDispatchEvent(IdeEventQueue.kt:675)
	at com.intellij.ide.IdeEventQueue.dispatchMouseEvent(IdeEventQueue.kt:621)
	at com.intellij.ide.IdeEventQueue._dispatchEvent$lambda$21(IdeEventQueue.kt:564)
	at com.intellij.openapi.application.impl.AnyThreadWriteThreadingSupport.runWriteIntentReadAction(AnyThreadWriteThreadingSupport.kt:128)
	at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.kt:564)
	at com.intellij.ide.IdeEventQueue.dispatchEvent$lambda$18$lambda$17$lambda$16$lambda$15(IdeEventQueue.kt:355)
	at com.intellij.openapi.progress.impl.CoreProgressManager.computePrioritized(CoreProgressManager.java:857)
	at com.intellij.ide.IdeEventQueue.dispatchEvent$lambda$18$lambda$17$lambda$16(IdeEventQueue.kt:354)
	at com.intellij.ide.IdeEventQueueKt.performActivity$lambda$2$lambda$1(IdeEventQueue.kt:1045)
	at com.intellij.openapi.application.WriteIntentReadAction.lambda$run$0(WriteIntentReadAction.java:24)
	at com.intellij.openapi.application.impl.AnyThreadWriteThreadingSupport.runWriteIntentReadAction(AnyThreadWriteThreadingSupport.kt:128)
	at com.intellij.openapi.application.impl.ApplicationImpl.runWriteIntentReadAction(ApplicationImpl.java:916)
	at com.intellij.openapi.application.WriteIntentReadAction.compute(WriteIntentReadAction.java:55)
	at com.intellij.openapi.application.WriteIntentReadAction.run(WriteIntentReadAction.java:23)
	at com.intellij.ide.IdeEventQueueKt.performActivity$lambda$2(IdeEventQueue.kt:1045)
	at com.intellij.ide.IdeEventQueueKt.performActivity$lambda$3(IdeEventQueue.kt:1054)
	at com.intellij.openapi.application.TransactionGuardImpl.performActivity(TransactionGuardImpl.java:117)
	at com.intellij.ide.IdeEventQueueKt.performActivity(IdeEventQueue.kt:1054)
	at com.intellij.ide.IdeEventQueue.dispatchEvent$lambda$18(IdeEventQueue.kt:349)
	at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.kt:395)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:207)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
	at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:92)
Caused by: java.lang.UnsupportedOperationException: JsonNull
	at com.google.gson.JsonElement.getAsString(JsonElement.java:252)
	at de.marhali.easyi18n.io.parser.json.JsonMapper.read(JsonMapper.java:37)
	at de.marhali.easyi18n.io.parser.json.JsonParserStrategy.read(JsonParserStrategy.java:50)
	at de.marhali.easyi18n.io.IOHandler.read(IOHandler.java:79)
	... 62 more