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 java.lang.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
java.lang.String	generateDisplayNameForClass(java.lang.Class<?> testClass)	Generate a display name for the given top-level or static nested test class.
default java.lang.String	generateDisplayNameForMethod(java.lang.Class<?> testClass, java.lang.reflect.Method testMethod)	Deprecated. in favor of generateDisplayNameForMethod(List, Class, Method)
default java.lang.String	generateDisplayNameForMethod(java.util.List<java.lang.Class<?>> enclosingInstanceTypes, java.lang.Class<?> testClass, java.lang.reflect.Method testMethod)	Generate a display name for the given method.
default java.lang.String	generateDisplayNameForNestedClass(java.lang.Class<?> nestedClass)	Deprecated. in favor of generateDisplayNameForNestedClass(List, Class)
default java.lang.String	generateDisplayNameForNestedClass(java.util.List<java.lang.Class<?>> enclosingInstanceTypes, java.lang.Class<?> nestedClass)	Generate a display name for the given @Nested inner test class.
static DisplayNameGenerator	getDisplayNameGenerator(java.lang.Class<?> generatorClass)	Return the DisplayNameGenerator instance corresponding to the given Class.
static java.lang.String	parameterTypesAsString(java.lang.reflect.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 Detail

DEFAULT_GENERATOR_PROPERTY_NAME

@API(status=STABLE,
     since="5.9")
static final java.lang.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 Detail

generateDisplayNameForClass

java.lang.String generateDisplayNameForClass(java.lang.Class<?> testClass)

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

If this method 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

@API(status=DEPRECATED,
     since="5.12")
@Deprecated
default java.lang.String generateDisplayNameForNestedClass(java.lang.Class<?> nestedClass)

Deprecated.

in favor of generateDisplayNameForNestedClass(List, Class)

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

If this method 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

generateDisplayNameForNestedClass

@API(status=MAINTAINED,
     since="5.13.3")
default java.lang.String generateDisplayNameForNestedClass(java.util.List<java.lang.Class<?>> enclosingInstanceTypes,
                                                           java.lang.Class<?> nestedClass)

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

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

Parameters:

enclosingInstanceTypes - the runtime types of the enclosing instances for the test class, ordered from outermost to innermost, excluding nestedClass; never null

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

Returns:

the display name for the nested class; never blank

Since:

5.12

generateDisplayNameForMethod

@API(status=DEPRECATED,
     since="5.12")
@Deprecated
default java.lang.String generateDisplayNameForMethod(java.lang.Class<?> testClass,
                                                      java.lang.reflect.Method testMethod)

Deprecated.

in favor of generateDisplayNameForMethod(List, Class, Method)

Generate a display name for the given method.

If this method 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

generateDisplayNameForMethod

@API(status=MAINTAINED,
     since="5.13.3")
default java.lang.String generateDisplayNameForMethod(java.util.List<java.lang.Class<?>> enclosingInstanceTypes,
                                                      java.lang.Class<?> testClass,
                                                      java.lang.reflect.Method testMethod)

Generate a display name for the given method.

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

Parameters:

enclosingInstanceTypes - the runtime types of the enclosing instances for the test class, ordered from outermost to innermost, excluding testClass; never null

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

Since:

5.12

parameterTypesAsString

static java.lang.String parameterTypesAsString(java.lang.reflect.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(java.lang.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