MapStruct - 對映對映

使用 Mapstruct，我們可使用 @MapMapping 註解建立對映物件。其他對映規則與到目前為止看到的相同。

語法

@Mapper
public interface UtilityMapper {
   @MapMapping(valueDateFormat = "dd.MM.yyyy")
   Map<String, String> getMap(Map<Long, GregorianCalendar> source);
}

下面的示例演示了相同的內容。

示例

在 Eclipse 中，按 Mapping List 章節中更新的對映作為開啟專案。

使用以下程式碼建立 UtilityMapper.java −

UtilityMapper.java

package com.tutorialspoint.mapper;

import java.util.GregorianCalendar;
import java.util.Map;
import org.mapstruct.MapMapping;
import org.mapstruct.Mapper;

@Mapper
public interface UtilityMapper {
   @MapMapping(valueDateFormat = "dd.MM.yyyy")
   Map<String, String> getMap(Map<Long, GregorianCalendar> source);
}

使用以下程式碼建立 UtilityMapperTest.java −

UtilityMapperTest.java

package com.tutorialspoint.mapping;

import static org.junit.jupiter.api.Assertions.assertEquals;
import java.util.GregorianCalendar;
import java.util.HashMap;
import java.util.Map;
import org.junit.jupiter.api.Test;
import org.mapstruct.factory.Mappers;
import com.tutorialspoint.mapper.UtilityMapper;

public class UtilityMapperTest {
   private UtilityMapper utilityMapper = Mappers.getMapper(UtilityMapper.class);

   @Test
   public void testMapMapping() {
      Map<Long, GregorianCalendar> source = new HashMap<>();
      source.put(1L, new GregorianCalendar(2015, 3, 5));

      Map<String, String> target = utilityMapper.getMap(source);
      assertEquals("05.04.2015", target.get("1"));		
   }
}

執行以下命令以測試對映。

mvn clean test

輸出

一旦命令成功。驗證輸出。

mvn clean test
[INFO] Scanning for projects...
...
[INFO] --- maven-surefire-plugin:2.12.4:test (default-test) @ mapping ---
[INFO] Surefire report directory: \mvn\mapping\target\surefire-reports

-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running com.tutorialspoint.mapping.CarMapperTest
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.327 sec
Running com.tutorialspoint.mapping.DeliveryAddressMapperTest
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.001 sec
Running com.tutorialspoint.mapping.StudentMapperTest
Tests run: 2, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.001 sec
Running com.tutorialspoint.mapping.UtilityMapperTest
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.001 sec

Results :

Tests run: 5, Failures: 0, Errors: 0, Skipped: 0
...