Does Servlet Container create ServletConfig object if there are no init-params?

Question

I know, that when Servlet Container instantiates Servlet object, it also creates respective ServletConfig object, where it stored all init-params for that servlet (which we can later fetch via servlet by .getServletConfig().getInitParameter(..)

My question is what happens when we don't have any init-param in the servlet element? does the container still create ServletConfig with no init-params? (.getSevletConfig() does not return null, so I'm not sure whether ServletConfig is created in runtime when invoking this method, or container still creates that object with no init-params) or in this case, container does not create ServletConfig object? if it does, why we may need that ServletConfig object?

So you are asking whether `getSevletConfig()` will always create a new instance of `ServletConfig` if there are no init params ? — Svetlin Zarev, Mar 26 '19 at 12:28
Well, if Container does not create - then yes, that is the question, and why we may need that ServletConfig object in that case.. but who knows, maybe container creates that object at context startup. — Giorgi Tsiklauri, Mar 26 '19 at 12:30
At least tomcat creates only one such object per servlet: org/apache/catalina/core/StandardWrapper.java:124 (tomcat 8.5) — Svetlin Zarev, Mar 26 '19 at 12:34

score 1 · Accepted Answer · answered Mar 26 '19 at 13:56

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The ServletConfig does not contain only init params but also a reference to the ServletContext and the servlet name, so it makes sense even if no init param has been specified.

answered Mar 26 '19 at 13:56

Pino

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But the central purpose of it is exactly init-param.. as several books state this. So to answer the question: container still creates it on startup.. right? – Giorgi Tsiklauri Mar 26 '19 at 17:30
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Sure, on startup. – Pino Mar 26 '19 at 18:59

Does Servlet Container create ServletConfig object if there are no init-params?

1 Answers1