Change # of bits ValueWriter checks for BigDecimal

[changlinli]

Proposed Changes

Fixes #617 by changing the number of bits from 32 to 31.

Types of Changes

What types of changes does your code introduce to this project?
Put an x in the boxes that apply

• Bugfix (non-breaking change which fixes issue ValueWriter.writeFieldValue allows BigDecimals that are too big to be written #617)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation (correction or otherwise)
• Cosmetics (whitespace, appearance)

Checklist

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• All tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
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• Any dependent changes have been merged and published in related repositories

Further Comments

I've included a test, but I can't actually run it because

make deps
./mvnw -Ddeps.dir=$(pwd)/deps verify -Dit.test=ValueWriterTest

blows up with

[INFO] --- maven-bundle-plugin:3.2.0:manifest (bundle-manifest) @ amqp-client ---
[INFO] 
[INFO] --- groovy-maven-plugin:2.0:execute (remove-old-test-keystores) @ amqp-client ---
[INFO] 
[INFO] --- groovy-maven-plugin:2.0:execute (query-test-tls-certs-dir) @ amqp-client ---
GEN    /tmp/rabbitmq-test-instances/tls-certs GEN    /tmp/rabbitmq-test-instances/tls-certs/testca/cacert.pemmake[1]: *** [Makefile:41: /tmp/rabbitmq-test-instances/tls-certs/testca/cacert.pem] Error 1make: *** [/home/changlin/Projects/rabbitmq-java-client/deps/rabbit_common/mk/rabbitmq-run.mk:238: /tmp/rabbitmq-test-instances/tls-certs] Error 2
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  6.019 s
[INFO] Finished at: 2019-06-27T22:58:59-04:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.codehaus.gmaven:groovy-maven-plugin:2.0:execute (query-test-tls-certs-dir) on project amqp-client: Execution query-test-tls-certs-dir of goal org.codehaus.gmaven:groovy-maven-plugin:2.0:execute failed: org.apache.maven.plugin.MojoExecutionException: Failed to query test TLS certs directory with command: make -C /home/changlin/Projects/rabbitmq-java-client/deps/rabbit --no-print-directory show-test-tls-certs-dir DEPS_DIR=/home/changlin/Projects/rabbitmq-java-client/deps -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginExecutionException

[pivotal-issuemaster]

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[pivotal-issuemaster]

@changlinli Thank you for signing the Contributor License Agreement!

[changlinli]

Oh and it looks like scale wasn't be checked either, which would cause a similar class of bugs.

[acogoluegnes]

@changlinli Thanks!