diff options
| -rw-r--r-- | server/src/com/vaadin/server/VaadinSession.java | 25 |
1 files changed, 21 insertions, 4 deletions
diff --git a/server/src/com/vaadin/server/VaadinSession.java b/server/src/com/vaadin/server/VaadinSession.java index 61a3cfb077..844b7ff674 100644 --- a/server/src/com/vaadin/server/VaadinSession.java +++ b/server/src/com/vaadin/server/VaadinSession.java @@ -761,9 +761,25 @@ public class VaadinSession implements HttpSessionBindingListener, Serializable { /** * Locks this session to protect its data from concurrent access. Accessing * the UI state from outside the normal request handling should always lock - * the session and unlock it when done. To ensure that the lock is always - * released, you should typically wrap the code in a <code>try</code> block - * and unlock the session in <code>finally</code>: + * the session and unlock it when done. The preferred way to ensure locking + * is done correctly is to wrap your code using + * {@link UI#runSafely(Runnable)} (or + * {@link VaadinSession#runSafely(Runnable)} if you are only touching the + * session and not any UI), e.g.: + * + * <pre> + * myUI.runSafely(new Runnable() { + * @Override + * public void run() { + * // Here it is safe to update the UI. + * // UI.getCurrent can also be used + * myUI.getContent().setCaption("Changed safely"); + * } + * }); + * </pre> + * + * If you for whatever reason want to do locking manually, you should do it + * like: * * <pre> * session.lock(); @@ -773,7 +789,7 @@ public class VaadinSession implements HttpSessionBindingListener, Serializable { * session.unlock(); * } * </pre> - * <p> + * * This method will block until the lock can be retrieved. * <p> * {@link #getLockInstance()} can be used if more control over the locking @@ -781,6 +797,7 @@ public class VaadinSession implements HttpSessionBindingListener, Serializable { * * @see #unlock() * @see #getLockInstance() + * @see #hasLock() */ public void lock() { getLockInstance().lock(); |