arez.persist.runtime.Registry Maven / Gradle / Ivy
The newest version!
package arez.persist.runtime;
import arez.Disposable;
import arez.SafeProcedure;
import grim.annotations.OmitSymbol;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.Objects;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import static org.realityforge.braincheck.Guards.*;
/**
* A utility class that contains references to stores and the root scope.
* This is extracted to a separate class to eliminate the from {@link ArezPersist} and thus
* make it much easier for GWT to optimize out code based on build time compilation parameters.
*/
final class Registry
{
/**
* The map of registered stores.
*/
@Nonnull
private static final Map c_stores = new HashMap<>();
/**
* The map of converters for application types.
*/
@Nonnull
private static final Map, Converter> c_converters = new HashMap<>();
/**
* The root scope.
*/
@Nullable
private static Scope c_rootScope = Scope.create( null, Scope.ROOT_SCOPE_NAME );
static
{
// register "app" store if enabled.
ArezPersist.registerApplicationStoreIfEnabled();
}
private Registry()
{
}
/**
* Return the root scope under which all other scopes are nested.
*
* @return the root scope under which all other scopes are nested.
*/
@Nonnull
static Scope getRootScope()
{
if ( null == c_rootScope )
{
c_rootScope = Scope.create( null, Scope.ROOT_SCOPE_NAME );
}
return c_rootScope;
}
/**
* Dispose the specified scope.
* A dispose operation first performs a {@link #releaseScope(Scope)} on the scope, then attempts to
* dispose all nested scopes and finally disposes the specified scope. A disposed scope should no longer be
* used to store state. It is an error to attempt to dispose the root scope.
*
* @param scope the scope to dispose.
*/
static void disposeScope( @Nonnull final Scope scope )
{
if ( ArezPersist.shouldCheckApiInvariants() )
{
apiInvariant( () -> Disposable.isNotDisposed( scope ),
() -> "disposeScope() passed a disposed scope named '" + scope.getName() + "'" );
}
releaseScope( scope );
_disposeScope( scope );
}
/**
* Release the specified scope.
* A release operation removes any state associated with the scope and any nested scope.
*
* @param scope the scope to release.
*/
static void releaseScope( @Nonnull final Scope scope )
{
if ( ArezPersist.shouldCheckApiInvariants() )
{
apiInvariant( () -> Disposable.isNotDisposed( scope ),
() -> "releaseScope() passed a disposed scope named '" + scope.getName() + "'" );
}
c_stores.values().forEach( store -> store.releaseScope( scope ) );
}
private static void _disposeScope( @Nonnull final Scope scope )
{
new ArrayList<>( scope.getNestedScopes() ).forEach( Registry::_disposeScope );
Disposable.dispose( scope );
}
/**
* Register a store with specified name and storage service.
* It is an error to register multiple stores with the same name.
*
* As part of the register operation, the store will attempt to restore state from the storage service.
* If an error occurs during the restore, then the error will be logged and registration will complete.
*
* @param name the name of the store.
* @param service the associated StorageService.
* @return the action to invoke to deregister service.
*/
static SafeProcedure registerStore( @Nonnull final String name, @Nonnull final StorageService service )
{
if ( ArezPersist.shouldCheckApiInvariants() )
{
apiInvariant( () -> !c_stores.containsKey( name ),
() -> "registerStore() invoked with name '" + name +
"' but a store is already registered with that name" );
}
final Store store = new Store( service );
c_stores.put( name, store );
try
{
store.restore();
}
catch ( final Throwable t )
{
LogUtil.getLogger().log( "Failed to restore state for store named '" + name + "'", t );
}
return () -> deregisterStore( name );
}
/**
* Deregister a store with the specified name.
*
* @param name the name of the store.
*/
private static void deregisterStore( @Nonnull final String name )
{
final Store store = c_stores.remove( name );
if ( null != store )
{
assert !store.isDisposed();
store.dispose();
}
}
/**
* Return the store that is registered with the specified name.
* It is an error to invoke this method without registering a store under this name.
*
* @param name the name of the store.
* @return the store.
*/
@Nonnull
static Store getStore( @Nonnull final String name )
{
if ( ArezPersist.shouldCheckApiInvariants() )
{
apiInvariant( () -> c_stores.containsKey( name ),
() -> "getStore() invoked with name " + name + " but no such store exists" );
}
return Objects.requireNonNull( c_stores.get( name ) );
}
/**
* Register a converter for a type.
* It is an error to register multiple converters with the same name.
*
* @param type the application type.
* @param converter the converter.
* @return the action to invoke to deregister converter.
*/
static SafeProcedure registerConverter( @Nonnull final Class type, @Nonnull final Converter converter )
{
if ( ArezPersist.shouldCheckApiInvariants() )
{
apiInvariant( () -> !c_converters.containsKey( type ),
() -> "registerConverter() invoked with type '" + type.getName() +
"' but a converter is already registered for that type" );
}
c_converters.put( type, converter );
return () -> c_converters.remove( type );
}
/**
* Return the converter registered for the specified application type or the identity converter if none are specified.
*
* @param type the application type.
* @return the converter if any.
*/
@SuppressWarnings( "unchecked" )
@Nonnull
static Converter getConverter( @Nonnull final Class type )
{
final Converter converter = (Converter) c_converters.get( type );
return null == converter ? IdentityConverter.instance() : converter;
}
@Nonnull
static Map getStores()
{
return c_stores;
}
@Nonnull
static Map, Converter> getConverters()
{
return c_converters;
}
/**
* cleanup service.
* This is dangerous as it may leave dangling references and should only be done in tests.
*/
@OmitSymbol
static void reset()
{
c_stores.values().forEach( Store::dispose );
c_stores.clear();
c_converters.clear();
ArezPersist.registerApplicationStoreIfEnabled();
if ( null != c_rootScope )
{
disposeScope( c_rootScope );
c_rootScope = null;
}
}
}