創建完模型之後，經常會報錯，是因爲沒有定義package。
xconfmanager --add com.ptc.core.meta.descriptor.server.impl.includeClassStartsWith=com.xxx.core.model -p定義包之後會有哪些好處呢？見官方文檔
The types of files that you should store under <Windchill>/src/com/mycompany include new Java source files, property files, HTML templates, RBINFO files, and XCONF files.
In addition to keeping your new packages and files in a <Windchill>/src/com/mycompany directory structure, you must include corresponding packages and files in your runtime system. For example, the following list explains where your files should be placed:
Java files are typically compiled to a comparable directory under <Windchill>/codebase. For example, if you create a class under <Windchill>/src/com/mycompany/part, you could compile it to <Windchill>/codebase/com/mycompany/part.
Resource bundle files must be compiled into a directory under <Windchill>/codebase at runtime. This can be done using the ResourceBuild command. For example, if you have new RBINFO files in the directory <Windchill>/src/com/mycompany/part, you could compile them to the <Windchill>/codebase/com/mycompany/part directory by executing the following command from a windchill shell:
ResourceBuild com.mycompany.part
Property files maintained in a custom directory like <Windchill>/src/com/mycompany must be copied to a directory in <Windchill>/codebase at runtime.
Often when you integrate new packages and files into your existing environment, you must change files that were supplied by PTC. Be sure to manage these customized files as directed in earlier sections.