第一次尝试使用maven设置Google应用引擎骨架项目。我按照this page上的说明操作，但在运行mvn appengine:devserver时出现此错误：
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T E S T S
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Results :
Tests run: 0, Failures: 0, Errors: 0, Skipped: 0
[INFO]
[INFO] --- maven-war-plugin:2.3:war (default-war) @ test1104 ---
[INFO] Packaging webapp
[INFO] Assembling webapp [test1104] in [C:\Users\mshaham\maven\test1104\target\t
est1104-1.0-SNAPSHOT]
[INFO] Processing war project
[INFO] Copying webapp webResources [C:\Users\mshaham\maven\test1104/src/main/web
app/WEB-INF] to [C:\Users\mshaham\maven\test1104\target\test1104-1.0-SNAPSHOT]
[INFO] Copying webapp resources [C:\Users\mshaham\maven\test1104\src\main\webapp
]
[INFO] Webapp assembled in [1531 msecs]
[INFO] Building war: C:\Users\mshaham\maven\test1104\target\test1104-1.0-SNAPSHO
T.war
[INFO]
[INFO] <<< appengine-maven-plugin:1.7.5:devserver (default-cli) @ test1104 <<<
[INFO]
[INFO] --- appengine-maven-plugin:1.7.5:devserver (default-cli) @ test1104 ---
[INFO]
[INFO] Google App Engine Java SDK - Running Development Server
[INFO]
[INFO] Retrieving Google App Engine Java SDK from Maven
[INFO] Running C:\Program Files\Java\jdk1.7.0_05\jre\bin\java -javaagent:\\serve
r\profiles\mshaham\.m2\repository\com\google\appengine\appengine-java-sdk\1.7.5\
appengine-java-sdk\appengine-java-sdk-1.7.5\lib\agent\appengine-agent.jar -Xboot
classpath/p:\\server\profiles\mshaham\.m2\repository\com\google\appengine\appeng
ine-java-sdk\1.7.5\appengine-java-sdk\appengine-java-sdk-1.7.5\lib\override\appe
ngine-dev-jdk-overrides.jar -classpath \\server\profiles\mshaham\.m2\repository\
com\google\appengine\appengine-java-sdk\1.7.5\appengine-java-sdk\appengine-java-
sdk-1.7.5\lib\appengine-tools-api.jar com.google.appengine.tools.development.Dev
AppServerMain C:\Users\mshaham\maven\test1104\target/test1104-1.0-SNAPSHOT
[INFO] java.lang.reflect.InvocationTargetException
[INFO] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[INFO] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.
java:57)
[INFO] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAcces
sorImpl.java:43)
[INFO] at java.lang.reflect.Method.invoke(Method.java:601)
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 12.247s
[INFO] Finished at: Thu Apr 11 12:20:34 IDT 2013
[INFO] Final Memory: 8M/92M
[INFO] ------------------------------------------------------------------------