在 DevMode 中看到 Twig Load 错误，但在 GAE 中没有看到

Question

当尝试使用 Twig（见下文）加载时，我在本地开发模式中看到了一个异常，而我们在 Live GAE 中看不到。

我的同事也没有看到它，但我们有相同的开发设置 （尽管他在 Mac 上运行）

失败的项目是 ArrayList，其中 ContactStatus 是一个简单的枚举（见下文），这是模型 声明

List<ContactStatus> contactStatuses = new ArrayList<ContactStatus>();

据我了解，这应该是开箱即用的？

不需要 @Child 注释等？ （事实上​​，添加 @Embedded 似乎 导致问题 35 ：http://code.google.com/p/ twig-persist/issues/detail?id=35)

当我运行调试会话时，这似乎失败了，因为 ArrayList 没有实现Comparable（因为Enum总是这样做）

我们做错了什么？！

版本

• Java 7
• Twig 2.0-beta3
• AppEngine 1.6.2.1
• GWT 2.4.0

Enum

public enum ContactStatus implements IsSerializable, Serializable {
   Public, Secret, Blocked, Ignored;
}

我们在开发模式中看到的异常

java.lang.IllegalArgumentException: Cannot compare [SimpleProperty value=[Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored] path=contactStatuses indexed=false] with [SimpleProperty value=[Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Blocked, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored, Ignored] path=contactStatuses indexed=false]
at com.google.code.twig.util.PropertyComparator.compare(PropertyComparator.java:23)
at com.google.code.twig.util.PropertyComparator.compare(PropertyComparator.java:7)
at java.util.TreeMap.compare(TreeMap.java:1188)
at java.util.TreeMap.put(TreeMap.java:531)
at java.util.TreeSet.add(TreeSet.java:255)
at java.util.AbstractCollection.addAll(AbstractCollection.java:334)
at java.util.TreeSet.addAll(TreeSet.java:312)
at com.google.code.twig.standard.StandardDecodeCommand.entityToInstance(StandardDecodeCommand.java:60)
at com.google.code.twig.standard.StandardDecodeCommand.keyToInstance(StandardDecodeCommand.java:127)
at com.google.code.twig.standard.StandardSingleTypedLoadCommand.keyToInstance(StandardSingleTypedLoadCommand.java:9)
at com.google.code.twig.standard.StandardSingleTypedLoadCommand.now(StandardSingleTypedLoadCommand.java:34)
at com.google.code.twig.standard.TranslatorObjectDatastore.load(TranslatorObjectDatastore.java:202)
at com.recruitmentlink.server.persistence.twig.TwigProfileImpl.getExistingCandidate(TwigProfileImpl.java:92)

Answer 1

以下是约翰·帕特森 (John Patterson) 就该问题以及相关代码“修复”做出的（超快速）回复，该代码“修复”抑制了这种不必要的“异常”

http://groups.google.com/group/twig-persist/browse_frm/thread/81b7d913a2ad37cc#

该问题仅影响使用 Java 7 的用户

。由于 GAE 部署运行的是 Java 6，我们在现场没有看到这个问题。