content: package com.alibaba.fastjson2.v1issues.issue_1800;
  
  import com.alibaba.fastjson2.JSON;
  import com.alibaba.fastjson2.JSONReader;
  import com.alibaba.fastjson2.annotation.JSONCreator;
  import com.alibaba.fastjson2.annotation.JSONField;
  import com.alibaba.fastjson2.reader.ObjectReader;
  import com.alibaba.fastjson2.reader.ObjectReaderCreator;
  import org.junit.jupiter.api.Test;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertNotNull;
  
  public class Issue1879 {
      @Test
      public void test_for_issue() throws Exception {
          String json = "{\n" +
                  "   \"ids\" : \"1,2,3\"\n" +
                  "}";
          M1 m = JSON.parseObject(json, M1.class);
      }
  
      @Test
      public void test_for_issue_2() throws Exception {
          String json = "{\n" +
                  "   \"ids\" : \"1,2,3\"\n" +
                  "}";
          M2 m = JSON.parseObject(json, M2.class);
          assertNotNull(m);
      }
  
      @Test
      public void test_for_issue_2_creators() throws Exception {
          ObjectReaderCreator[] creators = new ObjectReaderCreator[]{
                  ObjectReaderCreator.INSTANCE,
  //                ObjectReaderCreatorLambda.INSTANCE,
  //                ObjectReaderCreatorASM.INSTANCE,
          };
  
          String json = "{\n" +
                  "   \"ids\" : \"1,2,3\"\n" +
                  "}";
  
          for (ObjectReaderCreator creator : creators) {
              ObjectReader<M2> objectReader = creator.createObjectReader(M2.class);
              M2 m = objectReader.readObject(
                      JSONReader.of(json));
              assertNotNull(m);
              assertNotNull(m.ids);
              assertEquals(3, m.ids.size());
          }
      }
  
      public static class M1 {
          private List<Long> ids;
  
          @JSONCreator
          public M1(@JSONField(name = "ids") String ids) {
              this.ids = new ArrayList<Long>();
              for (String id : ids.split(",")) {
                  this.ids.add(Long.valueOf(id));
              }
          }
      }
  
      public static class M2 {
          private List<Long> ids;
  
          public List<Long> getIds() {
              return ids;
          }
  
          public void setIds(List<Long> ids) {
              this.ids = ids;
          }
      }
  }
  