Module org.junit.jupiter.api

Package org.junit.jupiter.api

Interface DisplayNameGenerator

All Known Implementing Classes:

DisplayNameGenerator.IndicativeSentences, DisplayNameGenerator.ReplaceUnderscores, DisplayNameGenerator.Simple, DisplayNameGenerator.Standard

@API(status=STABLE,
     since="5.7")
public interface DisplayNameGenerator

DisplayNameGenerator defines the SPI for generating display names programmatically.

Display names are typically used for test reporting in IDEs and build tools and may contain spaces, special characters, and even emoji.

Concrete implementations must have a default constructor.

A DisplayNameGenerator can be configured globally for the entire test suite via the "junit.jupiter.displayname.generator.default" configuration parameter (see the User Guide for details) or locally for a test class via the @DisplayNameGeneration annotation.

Built-in Implementations

• DisplayNameGenerator.Standard
• DisplayNameGenerator.Simple
• DisplayNameGenerator.ReplaceUnderscores
• DisplayNameGenerator.IndicativeSentences

Since:

5.4

See Also:

• @DisplayName
• @DisplayNameGeneration

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	DisplayNameGenerator.IndicativeSentences	DisplayNameGenerator that generates complete sentences.
static class	DisplayNameGenerator.ReplaceUnderscores	DisplayNameGenerator that replaces underscores with spaces.
static class	DisplayNameGenerator.Simple	Simple DisplayNameGenerator that removes trailing parentheses for methods with no parameters.
static class	DisplayNameGenerator.Standard	Standard DisplayNameGenerator.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DEFAULT_GENERATOR_PROPERTY_NAME	Property name used to set the default display name generator class name: "junit.jupiter.displayname.generator.default"

Method Summary

Modifier and Type	Method	Description
String	generateDisplayNameForClass(Class<?> testClass)	Generate a display name for the given top-level or static nested test class.
String	generateDisplayNameForMethod(Class<?> testClass, Method testMethod)	Generate a display name for the given method.
String	generateDisplayNameForNestedClass(Class<?> nestedClass)	Generate a display name for the given @Nested inner test class.
static DisplayNameGenerator	getDisplayNameGenerator(Class<?> generatorClass)	Return the DisplayNameGenerator instance corresponding to the given Class.
static String	parameterTypesAsString(Method method)	Generate a string representation of the formal parameters of the supplied method, consisting of the simple names of the parameter types, separated by commas, and enclosed in parentheses.

Field Details

DEFAULT_GENERATOR_PROPERTY_NAME

@API(status=STABLE,
     since="5.9")
static final String DEFAULT_GENERATOR_PROPERTY_NAME

Property name used to set the default display name generator class name: "junit.jupiter.displayname.generator.default"

Supported Values

Supported values include fully qualified class names for types that implement DisplayNameGenerator.

If not specified, the default is DisplayNameGenerator.Standard.

Since:

5.5

See Also:

• Constant Field Values

Method Details

generateDisplayNameForClass

String generateDisplayNameForClass(Class<?> testClass)

Generate a display name for the given top-level or static nested test class.

If it returns null, the default display name generator will be used instead.

Parameters:

testClass - the class to generate a name for; never null

Returns:

the display name for the class; never blank

generateDisplayNameForNestedClass

String generateDisplayNameForNestedClass(Class<?> nestedClass)

Generate a display name for the given @Nested inner test class.

If it returns null, the default display name generator will be used instead.

Parameters:

nestedClass - the class to generate a name for; never null

Returns:

the display name for the nested class; never blank

generateDisplayNameForMethod

String generateDisplayNameForMethod(Class<?> testClass,
 Method testMethod)

Generate a display name for the given method.

If it returns null, the default display name generator will be used instead.

Parameters:

testClass - the class the test method is invoked on; never null

testMethod - method to generate a display name for; never null

Returns:

the display name for the test; never blank

Implementation Note:

The class instance supplied as testClass may differ from the class returned by testMethod.getDeclaringClass() — for example, when a test method is inherited from a superclass.

parameterTypesAsString

static String parameterTypesAsString(Method method)

Generate a string representation of the formal parameters of the supplied method, consisting of the simple names of the parameter types, separated by commas, and enclosed in parentheses.

Parameters:

method - the method from to extract the parameter types from; never null

Returns:

a string representation of all parameter types of the supplied method or "()" if the method declares no parameters

getDisplayNameGenerator

static DisplayNameGenerator getDisplayNameGenerator(Class<?> generatorClass)

Return the DisplayNameGenerator instance corresponding to the given Class.

Parameters:

generatorClass - the generator's Class; never null, has to be a DisplayNameGenerator implementation

Returns:

a DisplayNameGenerator implementation instance