引起：java.lang.ClassCastException：com.google.appengine.api.datastore.Text 无法转换为 java.lang.String

Question

I am trying to download a Excel on my local computer from my web application deployed on Google App Engine. The Entity from I get the data, have not Text fields.

All the fields are String. However, when I reach the line (String) catalogo.getProperty("des_definidor") in a object which des_definidor field is 538 characters length (and 538 bytes, I calculated), I get this error. I thought the characters limit for a String was 1500 bytes in an Entity field.

Someone knows what is the problem? Thanks you so much

Answer 1

to convert com.google.appengine.api.datastore.Text to a String use getValue method on Text:

String value = someText.getValue();

Ordinary Java strings indeed stored as properties in Entity objects are limited to 1500 bytes.

for more info, check Java documentation for App Engine API .