DeadlineExceededException at java.util.zip.ZipFile.open

During instance startup, large applications may see a DeadlineExceededException and the following stack trace:

Failed startup of context 
    com.google.apphosting.utils.jetty.RuntimeAppEngineWebAppContext
com.google.apphosting.api.DeadlineExceededException:
    This request started at (time) and was still executing at (time + 60 seconds).
at java.util.zip.ZipFile.open(Native Method)
at java.util.zip.ZipFile.<init>(ZipFile.java:227)
at java.util.zip.ZipFile.<init>(ZipFile.java:156)
at java.util.jar.JarFile.<init>(JarFile.java:153)
at java.util.jar.JarFile.<init>(JarFile.java:90)

This exception (including the reference to ZipFile.open ) means that App Engine was unable to extract the application’s JAR file within the 60 second request limit.

Generally, this means that the application is too large. Try to reduce the app’s size by removing unused code. Also, cut down on the size of included libraries by removing unused portions. Running the application through a code optimizer can also help.

This error can also appear during times when App Engine is experiencing an outage or is slow in general. In this case, the error will most likely resolve itself when App Engine returns to normal serving status.