content: package com.alibaba.fastjson2.reader;
  
  import com.alibaba.fastjson2.JSONException;
  import com.alibaba.fastjson2.JSONFactory;
  import com.alibaba.fastjson2.JSONReader;
  import com.alibaba.fastjson2.schema.JSONSchema;
  
  import java.lang.reflect.Field;
  import java.lang.reflect.Method;
  import java.lang.reflect.ParameterizedType;
  import java.lang.reflect.Type;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.Map;
  
  class FieldReaderCollectionMethodReadOnly<T>
          extends FieldReaderObject<T> {
      FieldReaderCollectionMethodReadOnly(
              String fieldName,
              Type fieldType,
              Class fieldClass,
              int ordinal,
              long features,
              String format,
              JSONSchema schema,
              Method setter,
              Field field
      ) {
          super(fieldName, fieldType, fieldClass, ordinal, features, format, null, null, schema, setter, field, null);
          Type itemType = null;
          if (fieldType instanceof ParameterizedType) {
              Type[] actualTypeArguments = ((ParameterizedType) fieldType).getActualTypeArguments();
              if (actualTypeArguments.length > 0) {
                  itemType = actualTypeArguments[0];
              }
          }
          this.itemType = itemType;
      }
  
      @Override
      public void accept(T object, Object value) {
          if (value == null) {
              return;
          }
  
          Collection collection;
          try {
              collection = (Collection) method.invoke(object);
          } catch (Exception e) {
              throw new JSONException("set " + fieldName + " error", e);
          }
  
          if (collection == Collections.EMPTY_LIST
                  || collection == Collections.EMPTY_SET
                  || collection == null
                  || collection.equals(value)) {
              if (schema != null) {
                  schema.assertValidate(collection);
              }
  
              return;
          }
  
          String name = collection.getClass().getName();
          if ("java.util.Collections$UnmodifiableRandomAccessList".equals(name)
                  || "java.util.Arrays$ArrayList".equals(name)
                  || "java.util.Collections$SingletonList".equals(name)
                  || name.startsWith("java.util.ImmutableCollections$")
                  || name.startsWith("java.util.Collections$Unmodifiable")) {
              return;
          }
  
          Collection values = (Collection) value;
          for (Object item : values) {
              if (item == null) {
                  collection.add(null);
                  continue;
              }
  
              if (item instanceof Map && itemType instanceof Class) {
                  if (!((Class) itemType).isAssignableFrom(item.getClass())) {
                      if (itemReader == null) {
                          itemReader = JSONFactory
                                  .getDefaultObjectReaderProvider()
                                  .getObjectReader(itemType);
                      }
                      item = itemReader.createInstance((Map) item, 0L);
                  }
              }
              collection.add(item);
          }
  
          if (schema != null) {
              schema.assertValidate(collection);
          }
      }
  
      @Override
      public boolean isReadOnly() {
          return true;
      }
  
      @Override
      public void readFieldValue(JSONReader jsonReader, T object) {
          if (initReader == null) {
              initReader = jsonReader
                      .getContext()
                      .getObjectReader(fieldType);
          }
          Object value = jsonReader.jsonb
                  ? initReader.readJSONBObject(jsonReader, fieldType, fieldName, 0)
                  : initReader.readObject(jsonReader, fieldType, fieldName, 0);
          accept(object, value);
      }
  }
  