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This example will define a virtual <env-entry> called mySpecialValue with value 4000 that is unique within the whole jvm. It will be put into JNDI at java:comp/env/mySpecialValue for every webapp deployed. Moreover, the boolean argument indicates that this value should override an env-entry of the same name in web.xml. If you don't want to override, then omit this argument or set it to false.
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