Jak używać elementów dopasowujących Hamcrest attachThat() do tworzenia przypadków testowych JUnit w Javie — kompletny samouczek

Opublikowany: 2022-02-05

Jak używać Hamcrest for testing ? Jakiś czas temu napisałem artykuł Hello World JUnit ze wszystkimi szczegółami. W tym samouczku omówimy kroki how to use Hamcrest to create JUnit dla twojego projektu Java.

Hamcrest to testing framework dla Javy z elementami dopasowującymi dołączonymi do platformy JUnit w celu tworzenia bardziej czytelnych testów jednostkowych Javy. Wypróbowałem go dzisiaj i absolutnie go uwielbiam.

Bardzo prosta i kompletna dokumentacja sprawia, że jest to idealne.

Jeśli masz jakiekolwiek z poniższych pytań, jesteś we właściwym miejscu:

Pisanie przypadków testowych JUnit w Javie przy użyciu Eclipse
Jak pisać junitowe przypadki testowe w Javie
Przykładowe przypadki testowe JUnit w Javie
Pisanie przypadków testowych JUnit przy użyciu Hamcrest Matchers
Korzyści z assertThat vs Assert z metodami Assert w testach JUnit
samouczek hamcrest assertthat()
Testowanie z Hamcrest

Zacznijmy:

Utwórz klasę Java CrunchifyHemcrestJUnitTest.java w środowisku Eclipse. Zamierzamy stworzyć 4 różne kategorie testów.

Twórz przypadki testowe JUnit dla Java List
Twórz przypadki testowe JUnit dla Java Map
Twórz przypadki testowe JUnit dla Java Object
Twórz przypadki testowe JUnit dla sprawdzania wartości Null

Oto najlepsi rywale Hamcrest:

jest()
maPozycje()
maRozmiar()
zawiera()
zawiera w dowolnym zamówieniu()

Poniższy samouczek obejmuje prawie wszystkie przypadki testowe matchers, które cały czas będą mijać. Po prostu zmodyfikuj, aby utworzyć fałszywe alarmy i tak dalej.

Musisz dodać poniżej zależność maven w swoim projekcie.

< dependency >

< groupId > org . hamcrest < / groupId >

< artifactId > hamcrest - all < / artifactId >

< version > 1.3 < / version >

< / dependency >

Po prostu dodaj to do pliku pom.xml . Jeśli nie widzisz pliku pom.xml, postępuj zgodnie z tym samouczkiem.

zawiera inanyorder-hamcrest-java-juni-test

Oto kompletny kod Java

Wystarczy kliknąć prawym przyciskiem myszy na klasę i Run As -> JUnit Test .

CrunchifyHamcrestJUnitTest.java

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package crunchify . com . java . tutorials ;

import org . hamcrest . collection . IsEmptyCollection ;

import org . hamcrest . collection . IsMapContaining ;

import org . hamcrest . core . IsNull ;

import org . junit . Test ;

import java . util . * ;

import static org . hamcrest . CoreMatchers . * ;

import static org . hamcrest . MatcherAssert . assertThat ;

import static org . hamcrest . Matchers . hasProperty ;

import static org . hamcrest . collection . IsCollectionWithSize . hasSize ;

import static org . hamcrest . collection . IsIterableContainingInAnyOrder . containsInAnyOrder ;

import static org . hamcrest . collection . IsIterableContainingInOrder . contains ;

/**

* @author Crunchify.com

* <p>

* Hamcrest JUnit Tutorials by Crunchify.com

* 1. Create JUnit testcases for Java List

* 2. Create JUnit testcases for Java Map

* 3. Create JUnit testcases for Java Object

* 4. Create JUnit testcases for Null Check

public class CrunchifyHamcrestJUnitTest {

// Testcase-1: JUnit for List

@Test

public void crunchifyListJUnitTests ( ) {

// List: An ordered collection (also known as a sequence). The user of this interface has precise control over where in the list each element is inserted.

// The user can access elements by their integer index (position in the list), and search for elements in the list.

List <String> company = Arrays . asList ( "Crunchify.com" , "Google.com" , "Facebook.com" ) ;

// asList(): Returns a fixed-size list backed by the specified array. Changes made to the array will be visible in the returned list,

// and changes made to the list will be visible in the array.

// The returned list is Serializable and implements RandomAccess.

List <String> crunchifyCompany = Arrays . asList ( "Crunchify.com" , "Google.com" , "Facebook.com" ) ;

crunchifyLog ( "\n~~~~~~~~~~~JUnit List Check Test~~~~~~~~~~~" ) ;

crunchifyLog ( "1) assertThat(company, is(crunchifyCompany)) check" ) ;

// A shortcut to the frequently used is(equalTo(x)).

assertThat ( company , is ( crunchifyCompany ) ) ;

crunchifyLog ( "2) .hasItems() check" ) ;

assertThat ( company , hasItems ( "Crunchify.com" ) ) ;

crunchifyLog ( "3) .hasSize() check" ) ;

assertThat ( company , hasSize ( 3 ) ) ;

assertThat ( company . size ( ) , is ( 3 ) ) ;

crunchifyLog ( "4) .contains() and .containsInAnyOrder() check" ) ;

assertThat ( company , contains ( "Crunchify.com" , "Google.com" , "Facebook.com" ) ) ;

assertThat ( company , containsInAnyOrder ( "Google.com" , "Crunchify.com" , "Facebook.com" ) ) ;

// FAIL

// assertThat(company, contains("Google.com", "Crunchify.com", "Facebook.com"));

crunchifyLog ( "5) .empty() check" ) ;

assertThat ( company , not ( IsEmptyCollection . empty ( ) ) ) ;

assertThat ( new ArrayList < > ( ) , IsEmptyCollection . empty ( ) ) ;

}

private void crunchifyLog ( String crunchifyText ) {

System . out . println ( crunchifyText ) ;

}

@Test

public void crunchifyMapJUnitTests ( ) {

Map < String , String > company = new HashMap < > ( ) ;

company . put ( "C" , "Crunchify.com" ) ;

company . put ( "G" , "Google.com" ) ;

company . put ( "F" , "Facebook.com" ) ;

// Map: An object that maps keys to values. A map cannot contain duplicate keys; each key can map to at most one value.

// This interface takes the place of the Dictionary class, which was a totally abstract class rather than an interface.

Map < String , String > crunchifyCompany = new HashMap < > ( ) ;

crunchifyCompany . put ( "C" , "Crunchify.com" ) ;

// put(): Associates the specified value with the specified key in this map (optional operation).

// If the map previously contained a mapping for the key, the old value is replaced by the specified value.

// (A map m is said to contain a mapping for a key k if and only if m.containsKey(k) would return true.)

crunchifyCompany . put ( "G" , "Google.com" ) ;

crunchifyCompany . put ( "F" , "Facebook.com" ) ;

crunchifyLog ( "\n~~~~~~~~~~~ JUnit Map Check Test - All tests will PASS in our example ~~~~~~~~~~~" ) ;

crunchifyLog ( "1) assertThat(company, is(crunchifyCompany) check" ) ;

assertThat ( company , is ( crunchifyCompany ) ) ;

crunchifyLog ( "2) assertThat(company.size(), is(3)) check" ) ;

assertThat ( company . size ( ) , is ( 3 ) ) ;

crunchifyLog ( "3) .hasEntry() check which creates a matcher for Maps matching at least one entry whose key equals the specified key & value." ) ;

assertThat ( company , IsMapContaining . hasEntry ( "C" , "Crunchify.com" ) ) ;

assertThat ( company , not ( IsMapContaining . hasEntry ( "G" , "Twitter.com" ) ) ) ;

crunchifyLog ( "4) .hasKey() creates a matcher for Maps matching at least one key that is equal to the specified key." ) ;

assertThat ( company , IsMapContaining . hasKey ( "F" ) ) ;

crunchifyLog ( "5) .hasValue() creates a matcher for Maps matching at least one key that is equal to the specified value." ) ;

assertThat ( company , IsMapContaining . hasValue ( "Crunchify.com" ) ) ;

}

@SuppressWarnings ( "unchecked" )

@Test

public void crunchifyObjectJUnitTests ( ) {

List <Company> list = Arrays . asList ( new Company ( "Crunchify" , 10 ) , new Company ( "Google" , 30000 ) ) ;

assertThat ( list , hasItems ( new Company ( "Crunchify" , 10 ) , new Company ( "Google" , 30000 ) ) ) ;

assertThat ( list , containsInAnyOrder ( new Company ( "Google" , 30000 ) , new Company ( "Crunchify" , 10 ) ) ) ;

assertThat ( list , containsInAnyOrder ( hasProperty ( "name" , is ( "Google" ) ) , hasProperty ( "name" , is ( "Crunchify" ) ) ) ) ;

crunchifyLog ( "\n~~~~~~~~~~~ JUnit Object Check Test Completed ~~~~~~~~~~~" ) ;

}

// Create Company Object

public static class Company {

public Company ( String name , int employeeCount ) {

this . name = name ;

this . employeeCount = employeeCount ;

}

private String name ;

private int employeeCount ;

public int getEmployeeCount ( ) {

return employeeCount ;

}

public void setEmployeeCount ( int employeeCount ) {

this . employeeCount = employeeCount ;

}

public String getName ( ) {

return name ;

}

public void setName ( String name ) {

this . name = name ;

}

// Test equal, override equals() and hashCode()

@Override

public boolean equals ( Object c ) {

if ( this == c )

return true ;

if ( c == null | | getClass ( ) ! = c . getClass ( ) )

return false ;

Company fruit = ( Company ) c ;

return employeeCount == fruit . employeeCount && Objects.equals(name, fruit.name);

}

@Override

public int hashCode ( ) {

return Objects . hash ( name , employeeCount ) ;

}

@Test

public void crunchifyNullCheckJUnitTest ( ) {

// Two ways to check isNull

assertThat ( null , is ( nullValue ( ) ) ) ;

assertThat ( null , is ( IsNull . nullValue ( ) ) ) ;

// Two ways to check isNotNull

assertThat ( "crunchify" , is ( notNullValue ( ) ) ) ;

assertThat ( "crunchify" , is ( IsNull . notNullValue ( ) ) ) ;

crunchifyLog ( "\n~~~~~~~~~~~ JUnit Null Check Test Completed ~~~~~~~~~~~" ) ;

}

Dane wyjściowe konsoli Eclipse:

Po prostu uruchom powyższy program jako aplikację Java i powinieneś zobaczyć wynik jak poniżej.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ JUnit Object Check Test Completed ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ JUnit Null Check Test Completed ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ JUnit List Check Test ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

1 ) assertThat ( company , is ( crunchifyCompany ) ) check

2 ) . hasItems ( ) check

3 ) . hasSize ( ) check

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ JUnit List Check Test ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

1 ) assertThat ( company , is ( crunchifyCompany ) ) check

2 ) . hasItems ( ) check

3 ) . hasSize ( ) check

4 ) . contains ( ) and . containsInAnyOrder ( ) check

5 ) . empty ( ) check

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ JUnit Map Check Test - All tests will PASS in our example ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

1 ) assertThat ( company , is ( crunchifyCompany ) check

2 ) assertThat ( company . size ( ) , is ( 3 ) ) check

3 ) . hasEntry ( ) check which creates a matcher for Maps matching at least one entry whose key equals the specified key & value .

4 ) . hasKey ( ) creates a matcher for Maps matching at least one key that is equal to the specified key .

5 ) . hasValue ( ) creates a matcher for Maps matching at least one key that is equal to the specified value .

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ JUnit Object Check Test Completed ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ JUnit Null Check Test Completed ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Process finished with exit code 0

Daj nam znać, jeśli napotkasz jakikolwiek problem z działaniem powyższego programu.