*
   * <p><b>Note:</b> this method does not return the number of <i>distinct elements</i> in the
   * multiset, which is given by {@code entrySet().size()}.
   */
  @Override
  int size();

  /**
   * Returns the number of occurrences of an element in this multiset (the <i>count</i> of the

    return requireNonNull(DEST_TL.get());
  }

  /**
   * A thread-local destination buffer to keep us from creating new buffers. The starting size is
   * 1024 characters. If we grow past this we don't put it back in the threadlocal, we just keep
   * going and grow as needed.
   */
  private static final ThreadLocal<char[]> DEST_TL =
      new ThreadLocal<char[]>() {

  }

  /**
   * Returns the number of key-value mappings in this map. If the map contains more than {@code
   * Integer.MAX_VALUE} elements, returns {@code Integer.MAX_VALUE}.
   */
  public int size() {
    return map.size();
  }

  /** Returns {@code true} if this map contains no key-value mappings. */
  public boolean isEmpty() {
    return map.isEmpty();
  }

  /**

```JSON
{
  "title": "towel",
  "size": "XL"
}
```

받은 body를 포함해 데이터가 유효하지 않다고 알려주는 응답을 받게 됩니다:

```JSON hl_lines="12-15"
{
  "detail": [
    {
      "loc": [
        "body",
        "size"
      ],
      "msg": "value is not a valid integer",
      "type": "type_error.integer"
    }
  ],
  "body": {
    "title": "towel",
    "size": "XL"
  }
}
```

        dataStoreParams.put("key2", 123);
        dataStoreParams.put("key3", null);

        Map<String, Object> map = dataStoreParams.asMap();

        assertNotNull(map);
        assertEquals(3, map.size());
        assertEquals("value1", map.get("key1"));
        assertEquals(123, map.get("key2"));
        assertNull(map.get("key3"));

        // Verify that returned map is a copy
        map.put("key4", "value4");

      }

      OPCODE_CONTROL_CLOSE -> {
        var code = CLOSE_NO_STATUS_CODE
        var reason = ""
        val bufferSize = controlFrameBuffer.size
        if (bufferSize == 1L) {
          throw ProtocolException("Malformed close payload length of 1.")
        } else if (bufferSize != 0L) {
          code = controlFrameBuffer.readShort().toInt()

                        }
                      };
                    }
                  };
                }

                @Override
                public int size() {
                  return map.size();
                }

                @Override
                public boolean remove(Object o) {
                  return map.entrySet().remove(o);
                }

        int attributes = mockEntry.getAttributes();
        long createTime = mockEntry.createTime();
        long lastModified = mockEntry.lastModified();
        long lastAccess = mockEntry.lastAccess();
        long size = mockEntry.length();

        // Assert: values and interactions
        assertEquals("file.txt", name, "getName should return stubbed value");
        assertEquals(1, type1);
        assertEquals(1, type2);

      return head.getNextInWriteQueue() == head;
    }

    @Override
    public int size() {
      int size = 0;
      for (ReferenceEntry<K, V> e = head.getNextInWriteQueue();
          e != head;
          e = e.getNextInWriteQueue()) {
        size++;
      }
      return size;
    }

    @Override
    public void clear() {

        final ChatSource source = new ChatSource();
        source.setIndex(1);
        source.setTitle("Test Document");

        message.addSource(source);

        assertEquals(1, message.getSources().size());
        assertEquals("Test Document", message.getSources().get(0).getTitle());
    }

    @Test
    public void test_addSourceWithNullSources() {
        final ChatMessage message = new ChatMessage();