Why servlet is serializable

In other words: all classes you ever create, were or will be created are all serializable. This is a potential security hole - by coincidence you can serialize e. It's surprisingly easy to serialize random Java object, e. It's just safer to use white-list of classes which you explicitly want and allow to serialize as opposed to carefully examining your code, making sure no fields you do not desire are ever serialized. Moreover you can no longer say: MySuperSecretClass is not serializable by simply not implementing Serializable - you can only exclude the guts fields.

Since there are so few data in your example table, you will have to tell PostgreSQL to use an index scan:. Without the index both will use a sequential scan on the table, thereby reading all rows in the table. So both transactions will end up with a SIReadLock on the whole table. Even if you saved an int , that method expects an Object so your int will become an Integer due to auto-boxing.

Try to cast it back to Integer and it should be fine:. However, if the attribute is null you will get a NullPointerException here, so maybe it's better to go with Integer all the way:. Why does HttpServlet implement Serializable? Asked 4 Months ago Answers: 5 Viewed 41 times. Improve this question. Similar: Purpose of Serialization in webapplication — Basil Bourque. Add a comment. Active Oldest Votes. Improve this answer.

But who needs passivate a servlet, when it shall be thread-safe, and have no conversation state? It is so as to make cluster servers not fail and map session across in case o failures a similar bug verifies it, issues. Rastislav Komara Rastislav Komara 1, 8 8 silver badges 17 17 bronze badges. Is JNDI the only right way to set fields which aren't serialisable? It's so horrible. Well the Session is far more likely to be serialized than the servlet, so storing it there wouldn't mitigate the problem.

The following restrictions are imposed to meet these conditions: The container must accept objects that implement the Serializable interface. Migration of sessions will be handled by container-specific facilities. Maciek Kreft. This is a misleading answer. A servlet instance is normally not stored in the session. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password.

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