org.opentripplanner.updater.GraphUpdater Maven / Gradle / Ivy
package org.opentripplanner.updater;
/**
* Interface for graph updaters. Objects that implement this interface should always be configured
* via PreferencesConfigurable.configure after creating the object. GraphUpdaterConfigurator should
* take care of that. Beware that updaters run in separate threads at the same time.
*
* The only allowed way to make changes to the graph in an updater is by executing (anonymous)
* GraphWriterRunnable objects via GraphUpdaterManager.execute.
*
* Example implementations can be found in ExampleGraphUpdater and ExamplePollingGraphUpdater.
*/
public interface GraphUpdater {
/**
* Graph updaters must be aware of their manager to be able to execute GraphWriterRunnables.
* GraphUpdaterConfigurator should take care of calling this function.
*/
void setGraphUpdaterManager(WriteToGraphCallback saveResultOnGraph);
/**
* Here the updater can be initialized. If it throws, the updater won't be started (i.e. the run
* method won't be called). All updaters' setup methods will be run sequentially in a
* single-threaded manner before updates begin, in order to avoid concurrent reads/writes.
*/
//void setup(Graph graph, TransitModel transitModel) throws Exception;
/**
* This method will run in its own thread. It pulls or receives updates and applies them to the
* graph. It must perform any writes to the graph by passing GraphWriterRunnables to
* GraphUpdaterManager.execute(). This queues up the write operations, ensuring that only one
* updater performs writes at a time.
*/
void run() throws Exception;
/**
* Here the updater can clean up after itself.
*/
default void teardown() {}
/**
* Allow clients to wait for all realtime data to be loaded before submitting any travel plan
* requests. This does not block use of the OTP server. The client must voluntarily hit an
* endpoint and wait for readiness.
* TODO OTP2 This is really a bit backward. We should just run() the updaters once before scheduling them to poll,
* and not bring the router online until they have finished.
*/
default boolean isPrimed() {
return true;
}
/**
* This is the updater "type" used in the configuration file. It should ONLY be used to provide
* human friendly messages while logging and debugging.
*/
String getConfigRef();
}