CODEWITHSUNDEEP
javaunixubuntuamazon-web-servicesamazon-dynamodb
user1514879
user1514879

Reputation:

Amazon Web Services Java classpath

I am trying to run an application that reads and writes to the amazon dynamo DB. I downloaded the Eclipse toolkit and AWS SDK and if I run the application from my local PC it works perfectly. Next, I exported it to a jar file and uploaded it to my EC2 instance. However, when I run it there I get an error.

  /home/apps/java/database/bin$ java -jar myJar.jar
Exception in thread "main" java.lang.NoClassDefFoundError: com/amazonaws/auth/AW                                                                  SCredentials
Caused by: java.lang.ClassNotFoundException: com.amazonaws.auth.AWSCredentials
        at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
Could not find the main class: DynamoDB. Program will exit.

I assume it has to do with the classpath, but in /home/ubuntu/.bashrc I have set it as such: 

CLASSPATH="./:/home/apps/java/database/bin/*:/home/apps/java/database/bin/aws-java-sdk-1.3.12.jar"
export CLASSPATH

/home/apps/java/database/bin contains all the .jar files that are in the AWS SDK:

What am I missing?? I have been looking at this for a day and a half. Thank you in advance!!

Upvotes: 3

Views: 6190

Answers (2)

Iaroslav Malyshev
Iaroslav Malyshev

Reputation: 29

This list of libs works for me aws-java-sdk-1.11.285-javadoc.jar aws-java-sdk-1.11.285-sources.jar aws-java-sdk-1.11.285.jar aws-java-sdk.jar

aspectjrt-1.8.2.jar
aspectjweaver.jar
aws-swf-build-tools-1.1.jar
commons-codec-1.9.jar
commons-logging-1.1.3.jar
freemarker-2.3.9.jar
httpclient-4.5.2.jar
httpcore-4.4.4.jar
ion-java-1.0.2.jar
jackson-annotations-2.6.0.jarÅ
jackson-core-2.6.7.jar
jackson-databind-2.6.7.1.jar
jackson-dataformat-cbor-2.6.7.jar
javax.mail-api-1.4.6.jar
jmespath-java-1.11.285.jar
joda-time-2.8.1.jar
netty-buffer-4.1.17.Final.jar
netty-codec-4.1.17.Final.jar
netty-codec-http-4.1.17.Final.jar
netty-common-4.1.17.Final.jar
netty-handler-4.1.17.Final.jar
netty-resolver-4.1.17.Final.jar
netty-transport-4.1.17.Final.jar
spring-beans-3.0.7.RELEASE.jar
spring-context-3.0.7.RELEASE.jar
spring-core-3.0.7.RELEASE.jar
spring-test-3.0.7.RELEASE.jar

Upvotes: 0

300D7309EF17
300D7309EF17

Reputation: 24643

The classpath entry of "/directory/*" may be messing things up. Classpaths are separated with colons, but asterisk expansion gives spaces. Try this little shell script to start it.

#!/bin/sh
JAVA_OPTS="-Xms256M -Xmx4G"
CP=`find /home/apps/java/database/bin/*jar -exec echo -n "{}:" \;`
java -cp ${CP%?} -jar yourjar.jar

A couple of notes:

  • the JAVA_OPTS is only there as a reminder that you may need more memory than the default.
  • the crazy syntax for CP on the final line strips the last character, since the "find" line is leaving a colon on the end.
  • You may want to include your jar and launch the correct class if it isn't an executable jar.

Hope this helps!

Upvotes: 0

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