google-app-engine - GCS 客户端库 NoSuchMethod systemNanoTime

Question

当我调用 createOrReplace 时，

private GcsService gcsService = 
GcsOutputChannel outputChannel = gcsService.createOrReplace(file, GcsFileOptions.getDefaultInstance());

我明白了

java.lang.NoSuchMethodError: com.google.common.base.Platform.systemNanoTime()J
at com.google.common.base.Ticker$1.read(Ticker.java:60)
at com.google.common.base.Stopwatch.start(Stopwatch.java:114)
at com.google.appengine.tools.cloudstorage.RetryHelper.doRetry(RetryHelper.java:88)
at com.google.appengine.tools.cloudstorage.RetryHelper.runWithRetries(RetryHelper.java:138)
at com.google.appengine.tools.cloudstorage.GcsServiceImpl.createOrReplace(GcsServiceImpl.java:47)
at com.train.trainercircle.rest.ImageResource.getExercises(ImageResource.java:72)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:45)
at com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvokerFactory.java:60)
at 

我查看了 elipse 中的 pom 文件依赖管理器，并确保编译了 gcs-client 库所需的 guava 版本。

有什么建议，有什么想法吗？

谢谢

Answer 1

按照建议here您的类路径中可能有一个 google-collections jar 以及 Guava。确保将其删除。如果使用 Maven

<exclusions>
  <exclusion>
    <artifactId>google-collect</artifactId>
    <groupId>com.google</groupId>
  </exclusion>
</exclusions>

另见 here

Guava is a fully compatible superset of the old Google Collections Library. It also includes years worth of bug fixes, doc fixes, and performance fixes, so we strongly encourage you to use Guava instead of Google Collections.

If your application ever ends up with both google-collect-1.0.jar and guava-r##.jar on the same classpath, simply remove the Google Collections JAR and you should be fine. If you don't remove it, it will either cause terrible problems (if it comes before guava in the classpath) or will never even be seen anyway (if it comes after).