Package org.dbunit.annotation

Annotation Interface DbUnitColumnComparer

@Target({}) @Retention(RUNTIME) @Documented public @interface DbUnitColumnComparer
Binds one column to the ValueComparer used to compare its values, nested inside DbUnitVerifyTable.columnComparers().

comparer() is reflectively instantiated with its no-arg constructor. This reaches any custom ValueComparer, and the stateless ValueComparers constants - those whose implementation class has a no-arg constructor. It does not reach a ValueComparers constant that is a configured instance built with constructor arguments - the timestamp-tolerance comparers, for example isActualWithinOneMinuteNewerOfExpectedTimestamp; naming one of those here fails fast with an IllegalStateException pointing at a VerifyTableDefinitionsProvider catalog as the fix, since a configured comparer can only be expressed as a VerifyTableDefinition constant written in Java.

The instantiated comparer is cached for the JVM's entire lifetime, keyed by class, and reused by every later @DbUnitColumnComparer/DbUnitVerifyTable.defaultComparer() naming the same class, rather than reflectively constructed anew for every test method - the same once-and-reused-forever caching a VerifyTableDefinitionsProvider catalog gets. A custom ValueComparer named here must therefore be a pure function with no dependency on mutable external state that could legitimately differ between the tests reusing it.

Since:
3.6.0
Author:
Jeff Jensen
See Also:

  • Required Element Summary

    Required Elements
    Modifier and Type
    Required Element
    Description
    String
    column
    The name of the column this comparer applies to.
    Class<? extends ValueComparer>
    comparer
    The ValueComparer implementation to use for this column, instantiated with its no-arg constructor.

  • Element Details

    • column

      String column
      The name of the column this comparer applies to.
      Returns:
      The column name.

    • comparer

      Class<? extends ValueComparer> comparer
      The ValueComparer implementation to use for this column, instantiated with its no-arg constructor.
      Returns:
      The comparer class.