RoomDatabase.MigrationContainer

public static class RoomDatabase.MigrationContainer
extends Object

java.lang.Object
   ↳ androidx.room.RoomDatabase.MigrationContainer


A container to hold migrations. It also allows querying its contents to find migrations between two versions.

Summary

Public constructors

MigrationContainer()

Public methods

void addMigrations(List<Migration> migrations)

Adds the given migrations to the list of available migrations.

void addMigrations(Migration... migrations)

Adds the given migrations to the list of available migrations.

List<Migration> findMigrationPath(int start, int end)

Finds the list of migrations that should be run to move from start version to end version.

Map<Integer, Map<Integer, Migration>> getMigrations()

Returns the map of available migrations where the key is the start version of the migration, and the value is a map of (end version -> Migration).

Inherited methods

Public constructors

MigrationContainer

public MigrationContainer ()

Public methods

addMigrations

public void addMigrations (List<Migration> migrations)

Adds the given migrations to the list of available migrations. If 2 migrations have the same start-end versions, the latter migration overrides the previous one.

Parameters
migrations List: List of available migrations.

addMigrations

public void addMigrations (Migration... migrations)

Adds the given migrations to the list of available migrations. If 2 migrations have the same start-end versions, the latter migration overrides the previous one.

Parameters
migrations Migration: List of available migrations.

findMigrationPath

public List<Migration> findMigrationPath (int start, 
                int end)

Finds the list of migrations that should be run to move from start version to end version.

Parameters
start int: The current database version

end int: The target database version

Returns
List<Migration> An ordered list of Migration objects that should be run to migrate between the given versions. If a migration path cannot be found, returns null.

getMigrations

public Map<Integer, Map<Integer, Migration>> getMigrations ()

Returns the map of available migrations where the key is the start version of the migration, and the value is a map of (end version -> Migration).

Returns
Map<Integer, Map<Integer, Migration>> Map of migrations keyed by the start version