Session: How to check if there are any changes on a session?

Property indicates if session contains any changes. That is if there are any new, changed or deleted entities.

Syntax

public boolean hasChanges();

Example

try (IDocumentSession session = store.openSession()) {
  assertFalse(session.advanced().hasChanges());

  Employee employee = new Employee();
  employee.setFirstName("John");
  employee.setLastName("Doe");
  session.store(employee);

  assertTrue(session.advanced().hasChanges());
}

Method returns all changes for each entity stored within session. Including name of the field/property that changed, its old and new value and change type.

Syntax

public Map<String, List<DocumentsChanges>> whatChanged();

Example I

try (IDocumentSession session = store.openSession()) {
  Employee employee = new Employee();
  employee.setFirstName("John");
  employee.setLastName("Doe");
  session.store(employee);

  Map<String, List<DocumentsChanges>> changes = session.advanced().whatChanged();
  List<DocumentsChanges> employeeChanges = changes.get("employees/1");
  ChangeType change = employeeChanges.get(0).getChange(); // ChangeType.DOCUMENT_ADDED
}

Example II

try (IDocumentSession session = store.openSession()) {
  Employee employee = session.load(Employee.class, "employees/1"); // 'Joe Doe'
  employee.setFirstName("John");
  employee.setLastName("Shmoe");

  Map<String, List<DocumentsChanges>> changes = session.advanced().whatChanged();
  List<DocumentsChanges> employeeChanges = changes.get("employees/1");
  ChangeType change1 = employeeChanges.get(0).getChange(); // ChangeType.FIELD_CHANGED
  ChangeType change2 = employeeChanges.get(1).getChange(); // ChangeType.FIELD_CHANGED
}