How can I set session timeout so that it never expires?

How can I set session timeout so that it never expires? It's f开发者_如何学Cor a Java EE web application.

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Specify a negative time.

<session-config>
    <session-timeout>-1</session-timeout>
</session-config>

The benefit is however questionable. The webapp will leak memory away on long term. Think twice before you do this.