/**
* Change topology.
*
* @param parent Grid to execute tasks on.
* @param add New nodes count.
* @param rmv Remove nodes count.
* @param type Type of nodes to manipulate.
*/
private static void changeTopology(Ignite parent, int add, int rmv, String type) {
Collection<ComputeTaskFuture<?>> tasks = new ArrayList<>();
IgniteCompute comp = parent.compute().withAsync();
// Start nodes in parallel.
while (add-- > 0) {
comp.execute(ClientStartNodeTask.class, type);
tasks.add(comp.future());
}
for (ComputeTaskFuture<?> task : tasks) task.get();
// Stop nodes in sequence.
while (rmv-- > 0) parent.compute().execute(ClientStopNodeTask.class, type);
// Wait for node stops.
// U.sleep(1000);
Collection<String> gridNames = new ArrayList<>();
for (Ignite g : G.allGrids()) gridNames.add(g.name());
parent.log().info(">>> Available grids: " + gridNames);
}
/**
* Example for start/stop node tasks.
*
* @param args Not used.
*/
public static void main(String[] args) {
String nodeType = "tcp+ssl";
// Start initial node = 1
try (Ignite g = G.start(NODE_CFG.get(nodeType))) {
// Change topology.
changeTopology(g, 4, 1, nodeType);
changeTopology(g, 1, 4, nodeType);
// Stop node by id = 0
g.compute().execute(ClientStopNodeTask.class, g.cluster().localNode().id().toString());
// Wait for node stops.
// U.sleep(1000);
assert G.allGrids().isEmpty();
} catch (Exception e) {
System.err.println("Uncaught exception: " + e.getMessage());
e.printStackTrace(System.err);
}
}