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Session: How to defer operations?

Operations can be deferred till saveChanges is called by using defer method in advanced() session operations. There are four types of commands that can be deferred:

Syntax

public void defer(ICommandData... commands);

Parameters
ICommandData[] Array of commands implementing ICommandData interface.  

Example

Product product1 = new Product();
product1.setName("My Product");
product1.setSupplier("suppliers/999");

PutCommandData command1 = new PutCommandData();
command1.setKey("products/999");
command1.setDocument(RavenJObject.fromObject(product1));
command1.setMetadata(new RavenJObject());

session.advanced().defer(command1);

Supplier supplier = new Supplier();
supplier.setName("My Supplier");

PutCommandData command2 = new PutCommandData();
command2.setKey("suppliers/999");
command2.setDocument(RavenJObject.fromObject(supplier));
command2.setMetadata(new RavenJObject());

session.advanced().defer(command2);

DeleteCommandData deleteCommandData = new DeleteCommandData();
deleteCommandData.setKey("products/1");
session.advanced().defer(deleteCommandData);