AppSearchManager

public class AppSearchManager
extends Object

java.lang.Object
   ↳ android.app.appsearch.AppSearchManager

Provides access to the centralized AppSearch index maintained by the system.

AppSearch is an offline, on-device search library for managing structured data featuring:

Applications create a database by opening an AppSearchSession.

Example: 

 AppSearchManager appSearchManager = context.getSystemService(AppSearchManager.class);

 AppSearchManager.SearchContext searchContext = new AppSearchManager.SearchContext.Builder().
    setDatabaseName(dbName).build());
 appSearchManager.createSearchSession(searchContext, mExecutor, appSearchSessionResult -> {
      mAppSearchSession = appSearchSessionResult.getResultValue();
 });

After opening the session, a schema must be set in order to define the organizational structure of data. The schema is set by calling AppSearchSession.setSchema. The schema is composed of a collection of AppSearchSchema objects, each of which defines a unique type of data.

Example: 

 AppSearchSchema emailSchemaType = new AppSearchSchema.Builder("Email")
     .addProperty(new StringPropertyConfig.Builder("subject")
        .setCardinality(PropertyConfig.CARDINALITY_OPTIONAL)
        .setIndexingType(PropertyConfig.INDEXING_TYPE_PREFIXES)
        .setTokenizerType(PropertyConfig.TOKENIZER_TYPE_PLAIN)
    .build()
 ).build();

 SetSchemaRequest request = new SetSchemaRequest.Builder().addSchema(emailSchemaType).build();
 mAppSearchSession.set(request, mExecutor, appSearchResult -> {
      if (appSearchResult.isSuccess()) {
           // Schema has been successfully set.
      }
 });

The basic unit of data in AppSearch is represented as a GenericDocument object, containing an ID, namespace, time-to-live, score, and properties. A namespace organizes a logical group of documents. For example, a namespace can be created to group documents on a per-account basis. An ID identifies a single document within a namespace. The combination of namespace and ID uniquely identifies a GenericDocument in the database.

Once the schema has been set, GenericDocument objects can be put into the database and indexed by calling AppSearchSession.put.

Example: 

 // Although for this example we use GenericDocument directly, we recommend extending
 // GenericDocument to create specific types (i.e. Email) with specific setters/getters.
 GenericDocument email = new GenericDocument.Builder<>(NAMESPACE, ID, EMAIL_SCHEMA_TYPE)
     .setPropertyString(\u201csubject\u201d, EMAIL_SUBJECT)
     .setScore(EMAIL_SCORE)
     .build();

 PutDocumentsRequest request = new PutDocumentsRequest.Builder().addGenericDocuments(email)
     .build();
 mAppSearchSession.put(request, mExecutor, appSearchBatchResult -> {
      if (appSearchBatchResult.isSuccess()) {
           // All documents have been successfully indexed.
      }
 });

Searching within the database is done by calling AppSearchSession.search and providing the query string to search for, as well as a SearchSpec.

Alternatively, AppSearchSession.getByDocumentId can be called to retrieve documents by namespace and ID.

Document removal is done either by time-to-live expiration, or explicitly calling a remove operation. Remove operations can be done by namespace and ID via AppSearchSession.remove(android.app.appsearch.RemoveByDocumentIdRequest, java.util.concurrent.Executor, android.app.appsearch.BatchResultCallback), or by query via AppSearchSession.remove(String, SearchSpec, Executor, Consumer).

Summary

Nested classes

class AppSearchManager.SearchContext

Contains information about how to create the search session. 

Public methods

void createEnterpriseGlobalSearchSession(Executor executor, Consumer<AppSearchResult<EnterpriseGlobalSearchSession>> callback)

Creates a new EnterpriseGlobalSearchSession

EnterpriseGlobalSearchSession queries data from the user\u2019s work profile, allowing apps running on the personal profile to access a limited subset of work profile data.

void createGlobalSearchSession(Executor executor, Consumer<AppSearchResult<GlobalSearchSession>> callback)

Creates a new GlobalSearchSession.

void createSearchSession(AppSearchManager.SearchContext searchContext, Executor executor, Consumer<AppSearchResult<AppSearchSession>> callback)

Creates a new AppSearchSession.

Inherited methods

Public methods

createEnterpriseGlobalSearchSession

Added in API level 35
Also in T Extensions 13 
public void createEnterpriseGlobalSearchSession (Executor executor, 
                Consumer<AppSearchResult<EnterpriseGlobalSearchSession>> callback)

Creates a new EnterpriseGlobalSearchSession

EnterpriseGlobalSearchSession queries data from the user\u2019s work profile, allowing apps running on the personal profile to access a limited subset of work profile data. Enterprise access must be explicitly enabled on schemas, and schemas may also specify additional permissions required for enterprise access.

This process requires an AppSearch native indexing file system. If it's not created, the initialization process will create one under the user's credential encrypted directory.

Parameters
executor Executor: Executor on which to invoke the callback. This value cannot be null. Callback and listener events are dispatched through this Executor, providing an easy way to control which thread is used. To dispatch events through the main thread of your application, you can use Context.getMainExecutor(). Otherwise, provide an Executor that dispatches to an appropriate thread.
callback Consumer: The AppSearchResult<EnterpriseGlobalSearchSession> of performing this operation. Or a AppSearchResult with failure reason code and error information. This value cannot be null.

createGlobalSearchSession

Added in API level 31 
public void createGlobalSearchSession (Executor executor, 
                Consumer<AppSearchResult<GlobalSearchSession>> callback)

Creates a new GlobalSearchSession.

This process requires an AppSearch native indexing file system. If it's not created, the initialization process will create one under the user's credential encrypted directory.

Parameters
executor Executor: Executor on which to invoke the callback. This value cannot be null. Callback and listener events are dispatched through this Executor, providing an easy way to control which thread is used. To dispatch events through the main thread of your application, you can use Context.getMainExecutor(). Otherwise, provide an Executor that dispatches to an appropriate thread.
callback Consumer: The AppSearchResult<GlobalSearchSession> of performing this operation. Or a AppSearchResult with failure reason code and error information. This value cannot be null.

createSearchSession

Added in API level 31 
public void createSearchSession (AppSearchManager.SearchContext searchContext, 
                Executor executor, 
                Consumer<AppSearchResult<AppSearchSession>> callback)

Creates a new AppSearchSession.

This process requires an AppSearch native indexing file system. If it's not created, the initialization process will create one under the user's credential encrypted directory.

Parameters
searchContext AppSearchManager.SearchContext: The SearchContext contains all information to create a new AppSearchSession This value cannot be null.
executor Executor: Executor on which to invoke the callback. This value cannot be null. Callback and listener events are dispatched through this Executor, providing an easy way to control which thread is used. To dispatch events through the main thread of your application, you can use Context.getMainExecutor(). Otherwise, provide an Executor that dispatches to an appropriate thread.
callback Consumer: The AppSearchResult<AppSearchSession> of performing this operation. Or a AppSearchResult with failure reason code and error information. This value cannot be null.