Upgrading from v4

Migration guide for upgrading from CometChat Android SDK v4 to v5. Covers breaking changes to Gson removal, equals/hashCode behavior, and Parcelable support.

This guide covers the breaking changes in CometChat Android SDK v5 and what you need to update in your app.

Dependency Update

Update your build.gradle dependency:

dependencies {
  implementation "com.cometchat:chat-sdk-android:5.0.0"
}

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Breaking Changes Overview

SDK v5 removes the Gson dependency from all SDK model classes and changes equals() / hashCode() to structural (deep) equality. All SDK model classes now implement Parcelable.

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Must Do (will crash without these)

Replace Gson deserialization of SDK classes

Gson().fromJson(json, BaseMessage::class.java) no longer works because SDK classes no longer have Gson annotations.

Before (v4):

val message = Gson().fromJson(jsonString, BaseMessage::class.java)

After (v5):

val message = BaseMessage.processMessage(jsonObject)

For Conversation:

Before (v4):

val conversation = Gson().fromJson(jsonString, Conversation::class.java)

After (v5): Use Parcelable to pass between components, or reconstruct from the SDK’s fetch methods.

Replace Gson-based Intent/Bundle passing

All SDK model classes (User, Group, BaseMessage, Conversation, etc.) now implement Parcelable. Use putExtra() / IntentCompat.getParcelableExtra() instead of Gson serialization.

User

Before (v4):

// Sending
intent.putExtra("user", Gson().toJson(user))

// Receiving
val user = Gson().fromJson(intent.getStringExtra("user"), User::class.java)

After (v5):

// Sending
intent.putExtra(getString(R.string.app_user), user)

// Receiving
val user = IntentCompat.getParcelableExtra(intent, getString(R.string.app_user), User::class.java)

BaseMessage

Before (v4):

// Sending
intent.putExtra("message", Gson().toJson(baseMessage))

// Receiving
val message = Gson().fromJson(intent.getStringExtra("message"), BaseMessage::class.java)

After (v5):

// Sending
intent.putExtra(getString(R.string.app_message), baseMessage)

// Receiving
val message = IntentCompat.getParcelableExtra(intent, getString(R.string.app_message), BaseMessage::class.java)

Group

Before (v4):

// Sending
intent.putExtra("group", Gson().toJson(group))

// Receiving
val group = Gson().fromJson(intent.getStringExtra("group"), Group::class.java)

After (v5):

// Sending
intent.putExtra(getString(R.string.app_group), group)

// Receiving
val group = IntentCompat.getParcelableExtra(intent, getString(R.string.app_group), Group::class.java)

Conversation

Before (v4):

// Sending
intent.putExtra("conversation", Gson().toJson(conversation))

// Receiving
val conversation = Gson().fromJson(intent.getStringExtra("conversation"), Conversation::class.java)

After (v5):

// Sending
intent.putExtra(getString(R.string.app_conversation), conversation)

// Receiving
val conversation = IntentCompat.getParcelableExtra(intent, getString(R.string.app_conversation), Conversation::class.java)

This pattern applies to all SDK model classes — Call, Action, MediaMessage, TextMessage, CustomMessage, etc. They all implement Parcelable in v5.

Replace Gson clone hacks

Before (v4):

val clone = Gson().fromJson(Gson().toJson(original), User::class.java)

After (v5):

val clone = original.clone()

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Must Do (will cause silent bugs without these)

Update DiffUtil comparisons

equals() now does deep structural comparison. Using it in areItemsTheSame() will cause incorrect diff results.

Before (v4):

override fun areItemsTheSame(oldItem: User, newItem: User): Boolean {
    return oldItem == newItem // worked because equals() compared by UID
}

After (v5):

override fun areItemsTheSame(oldItem: User, newItem: User): Boolean {
    return oldItem.uid == newItem.uid // explicit ID comparison
}

Replace list contains/remove with ID-based operations

Before (v4):

if (userList.contains(user)) { ... }
userList.remove(user)

After (v5):

if (userList.any { it.uid == user.uid }) { ... }
userList.removeAll { it.uid == user.uid }

Stop using SDK objects as HashMap/HashSet keys

Before (v4):

val map = HashMap<User, SomeData>()
map[user] = data

After (v5):

val map = HashMap<String, SomeData>() // use UID as key
map[user.uid] = data

Add ProGuard keep rules

Add the following to your proguard-rules.pro:

-keep class com.cometchat.** { *; }
-keepclassmembers class com.cometchat.** {
    public boolean contentEquals(**);
}

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Should Review

These won’t crash but may cause unexpected behavior if your code relied on the old identity-based equality:

• Any code that relied on user1.equals(user2) meaning “same user” — it now means “identical in every field”
• Any code that relied on message1.equals(message2) meaning “same message” — it now means “identical in every field including read receipts, reactions, etc.”
• Any code comparing Conversations via equals() — now does recursive deep comparison of lastMessage and conversationWith

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Safe — No Changes Needed

These patterns continue to work without modification:

• Gson usage for your own custom DTOs (not SDK classes)
• User.fromJson(), Group.fromJson(), BaseMessage.processMessage() — these SDK methods still work
• user.toJson(), group.toMap() — these SDK serialization methods still work