spring-boot-rest/libraries-6/src/test/java/com/baeldung/modelmapper/ModelMapperUnitTest.java

package com.baeldung.modelmapper;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;
import static org.junit.jupiter.api.Assertions.assertNull;

import com.baeldung.modelmapper.domain.Game;
import com.baeldung.modelmapper.domain.GameMode;
import com.baeldung.modelmapper.domain.GameSettings;
import com.baeldung.modelmapper.domain.Player;
import com.baeldung.modelmapper.dto.GameDTO;
import com.baeldung.modelmapper.dto.PlayerDTO;
import com.baeldung.modelmapper.repository.GameRepository;
import java.time.Instant;
import java.util.Collection;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.modelmapper.Condition;
import org.modelmapper.Conditions;
import org.modelmapper.Converter;
import org.modelmapper.ModelMapper;
import org.modelmapper.Provider;
import org.modelmapper.TypeMap;
import org.modelmapper.convention.MatchingStrategies;

public class ModelMapperUnitTest {

    ModelMapper mapper;
    GameRepository gameRepository;

    @BeforeEach
    public void setup() {
        this.mapper = new ModelMapper();
        this.gameRepository = new GameRepository();
    }

    @Test
    public void whenMapGameWithExactMatch_thenConvertsToDTO() {
        // when similar source object is provided
        Game game = new Game(1L, "Game 1");
        GameDTO gameDTO = this.mapper.map(game, GameDTO.class);

        // then it maps without property mapper
        assertEquals(game.getId(), gameDTO.getId());
        assertEquals(game.getName(), gameDTO.getName());
    }

    @Test
    public void whenMapGameWithBasicPropertyMapping_thenConvertsToDTO() {
        // setup
        TypeMap<Game, GameDTO> propertyMapper = this.mapper.createTypeMap(Game.class, GameDTO.class);
        propertyMapper.addMapping(Game::getTimestamp, GameDTO::setCreationTime);

        // when field names are different
        Game game = new Game(1L, "Game 1");
        game.setTimestamp(Instant.now().getEpochSecond());
        GameDTO gameDTO = this.mapper.map(game, GameDTO.class);

        // then it maps via property mapper
        assertEquals(game.getId(), gameDTO.getId());
        assertEquals(game.getName(), gameDTO.getName());
        assertEquals(game.getTimestamp(), gameDTO.getCreationTime());
    }

    @Test
    public void whenMapGameWithDeepMapping_thenConvertsToDTO() {
        // setup
        TypeMap<Game, GameDTO> propertyMapper = this.mapper.createTypeMap(Game.class, GameDTO.class);
        // add deep mapping to flatten source's Player into name in destination
        propertyMapper.addMappings(
          mapper -> mapper.map(src -> src.getCreator().getName(), GameDTO::setCreator)
        );

        // when map between different hierarchies
        Game game = new Game(1L, "Game 1");
        game.setCreator(new Player(1L, "John"));
        GameDTO gameDTO = this.mapper.map(game, GameDTO.class);

        // then
        assertEquals(game.getId(), gameDTO.getId());
        assertEquals(game.getName(), gameDTO.getName());
        assertEquals(game.getCreator().getName(), gameDTO.getCreator());
    }

    @Test
    public void whenMapGameWithDifferentTypedProperties_thenConvertsToDTO() {
        // setup
        TypeMap<Game, GameDTO> propertyMapper = this.mapper.createTypeMap(Game.class, GameDTO.class);
        propertyMapper.addMappings(mapper -> mapper.map(src -> src.getCreator().getId(), GameDTO::setCreatorId));

        // when map different typed properties
        Game game = new Game(1L, "Game 1");
        game.setCreator(new Player(1L, "John"));
        GameDTO gameDTO = this.mapper.map(game, GameDTO.class);

        // then it converts between types
        assertEquals(game.getId(), gameDTO.getId());
        assertEquals(game.getName(), gameDTO.getName());
        assertEquals("1", gameDTO.getCreatorId());
    }

    @Test
    public void whenMapGameWithSkipIdProperty_thenConvertsToDTO() {
        // setup
        TypeMap<Game, GameDTO> propertyMapper = this.mapper.createTypeMap(Game.class, GameDTO.class);
        propertyMapper.addMappings(mapper -> mapper.skip(GameDTO::setId));

        // when id is skipped
        Game game = new Game(1L, "Game 1");
        GameDTO gameDTO = this.mapper.map(game, GameDTO.class);

        // then destination id is null
        assertNull(gameDTO.getId());
        assertEquals(game.getName(), gameDTO.getName());
    }

    @Test
    public void whenMapGameWithCustomConverter_thenConvertsToDTO() {
        // setup
        TypeMap<Game, GameDTO> propertyMapper = this.mapper.createTypeMap(Game.class, GameDTO.class);
        Converter<Collection, Integer> collectionToSize = c -> c.getSource().size();
        propertyMapper.addMappings(
          mapper -> mapper.using(collectionToSize).map(Game::getPlayers, GameDTO::setTotalPlayers)
        );

        // when collection to size converter is provided
        Game game = new Game(1L, "Game 1");
        game.setCreator(new Player(1L, "John"));
        game.addPlayer(new Player(2L, "Bob"));
        GameDTO gameDTO = this.mapper.map(game, GameDTO.class);

        // then it maps the size to a custom field
        assertEquals(game.getId(), gameDTO.getId());
        assertEquals(game.getName(), gameDTO.getName());
        assertEquals(game.getPlayers().size(), gameDTO.getTotalPlayers());
    }

    @Test
    public void whenUsingProvider_thenMergesGameInstances() {
        // setup
        TypeMap<Game, Game> propertyMapper = this.mapper.createTypeMap(Game.class, Game.class);
        // a provider to fetch a Game instance from a repository
        Provider<Game> gameProvider = p -> this.gameRepository.findById(1L);
        propertyMapper.setProvider(gameProvider);

        // when a state for update is given
        Game update = new Game(1L, "Game Updated!");
        update.setCreator(new Player(1L, "John"));
        Game updatedGame = this.mapper.map(update, Game.class);

        // then it merges the updates over on the provided instance
        assertEquals(1L, updatedGame.getId().longValue());
        assertEquals("Game Updated!", updatedGame.getName());
        assertEquals("John", updatedGame.getCreator().getName());
    }

    @Test
    public void whenUsingConditionalIsNull_thenMergesGameInstancesWithoutOverridingId() {
        // setup
        TypeMap<Game, Game> propertyMapper = this.mapper.createTypeMap(Game.class, Game.class);
        propertyMapper.setProvider(p -> this.gameRepository.findById(2L));
        propertyMapper.addMappings(mapper -> mapper.when(Conditions.isNull()).skip(Game::getId, Game::setId));

        // when game has no id
        Game update = new Game(null, "Not Persisted Game!");
        Game updatedGame = this.mapper.map(update, Game.class);

        // then destination game id is not overwritten
        assertEquals(2L, updatedGame.getId().longValue());
        assertEquals("Not Persisted Game!", updatedGame.getName());
    }

    @Test
    public void whenUsingCustomConditional_thenConvertsDTOSkipsZeroTimestamp() {
        // setup
        TypeMap<Game, GameDTO> propertyMapper = this.mapper.createTypeMap(Game.class, GameDTO.class);
        Condition<Long, Long> hasTimestamp = ctx -> ctx.getSource() != null && ctx.getSource() > 0;
        propertyMapper.addMappings(mapper -> mapper.when(hasTimestamp).map(Game::getTimestamp, GameDTO::setCreationTime));

        // when game has zero timestamp
        Game game = new Game(1L, "Game 1");
        game.setTimestamp(0L);
        GameDTO gameDTO = this.mapper.map(game, GameDTO.class);

        // then timestamp field is not mapped
        assertEquals(game.getId(), gameDTO.getId());
        assertEquals(game.getName(), gameDTO.getName());
        assertNotEquals(0L, gameDTO.getCreationTime());
        assertNull(gameDTO.getCreationTime());

        // when game has timestamp greater than zero
        game.setTimestamp(Instant.now().getEpochSecond());
        gameDTO = this.mapper.map(game, GameDTO.class);

        // then timestamp field is mapped
        assertEquals(game.getId(), gameDTO.getId());
        assertEquals(game.getName(), gameDTO.getName());
        assertEquals(game.getTimestamp(), gameDTO.getCreationTime());
        assertNotNull(gameDTO.getCreationTime());
    }

    @Test
    public void whenUsingLooseMappingStrategy_thenConvertsToDomainAndDTO() {
        // setup
        this.mapper.getConfiguration().setMatchingStrategy(MatchingStrategies.LOOSE);

        // when dto has flat fields for GameSetting
        GameDTO gameDTO = new GameDTO();
        gameDTO.setId(1L);
        gameDTO.setName("Game 1");
        gameDTO.setMode(GameMode.TURBO);
        gameDTO.setMaxPlayers(8);
        Game game = this.mapper.map(gameDTO, Game.class);

        // then it converts to inner objects without property mapper
        assertEquals(gameDTO.getId(), game.getId());
        assertEquals(gameDTO.getName(), game.getName());
        assertEquals(gameDTO.getMode(), game.getSettings().getMode());
        assertEquals(gameDTO.getMaxPlayers(), game.getSettings().getMaxPlayers());

        // when the GameSetting's field names match
        game = new Game(1L, "Game 1");
        game.setSettings(new GameSettings(GameMode.NORMAL, 6));
        gameDTO = this.mapper.map(game, GameDTO.class);

        // then it flattens the fields on dto
        assertEquals(game.getId(), gameDTO.getId());
        assertEquals(game.getName(), gameDTO.getName());
        assertEquals(game.getSettings().getMode(), gameDTO.getMode());
        assertEquals(game.getSettings().getMaxPlayers(), gameDTO.getMaxPlayers());
    }

    @Test
    public void whenConfigurationSkipNullEnabled_thenConvertsToDTO() {
        // setup
        this.mapper.getConfiguration().setSkipNullEnabled(true);
        TypeMap<Game, Game> propertyMap = this.mapper.createTypeMap(Game.class, Game.class);
        propertyMap.setProvider(p -> this.gameRepository.findById(2L));

        // when game has no id
        Game update = new Game(null, "Not Persisted Game!");
        Game updatedGame = this.mapper.map(update, Game.class);

        // then destination game id is not overwritten
        assertEquals(2L, updatedGame.getId().longValue());
        assertEquals("Not Persisted Game!", updatedGame.getName());
    }

    @Test
    public void whenConfigurationPreferNestedPropertiesDisabled_thenConvertsCircularReferencedToDTO() {
        // setup
        this.mapper.getConfiguration().setPreferNestedProperties(false);

        // when game has circular reference: Game -> Player -> Game
        Game game = new Game(1L, "Game 1");
        Player player = new Player(1L, "John");
        player.setCurrentGame(game);
        game.setCreator(player);
        GameDTO gameDTO = this.mapper.map(game, GameDTO.class);

        // then it resolves without any exception
        assertEquals(game.getId(), gameDTO.getId());
        assertEquals(game.getName(), gameDTO.getName());
        PlayerDTO playerDTO = gameDTO.getPlayers().get(0);
        assertEquals(player.getId(), playerDTO.getId());
        assertEquals(player.getCurrentGame().getId(), playerDTO.getCurrentGame().getId());
    }

}