anchor.diff:  https://maven.apache.org/plugins/maven-compiler-plugin/examples/set-compiler-source-and-target.html[configuration]
   of the `maven-compiler-plugin`.
   
  -[[do-not-require-web-descriptor]]
  -Do not require web descriptor
  -^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  -
  +=== Do not require web descriptor
   Web applications do not require a web descriptor (the `web.xml` file
   that goes in the `WEB-INF` folder). Maven however required it by default
   when asked to package a war file. If you do not need a web descriptor,
  
positive.code: delimited identifiers occurs when using an entity named `User`: this may
  work on some DBMS and fail at runtime on others.
  
  [[metamodel-generator-for-typesafe-jpa-queries]]
  Metamodel generator for typesafe JPA queries
  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  
  To generate the metamodel for use with typesafe Criteria queries,
  suffices to include a metamodel generator in your classpath
  (http://hibernate.org/orm/tooling/[doc]). Set it to `<provided>` scope
  
negative.code: metamodel, but I don’t use that as it hinders compatibility of the
  project with other IDEs.)
  
  == JSF best practices
  === [[multifield]]Multiple field validation
  Sometimes the validation logic requires knowledge of the value of
  multiple fields. (Example: required `start` ≤ `end`, where `start` and
  `end` are two request parameters.) In such case I consider the usual JSF
  