@Override
    public GetBlockResult getBlock(GetBlockRequest request) {
        request = beforeClientExecution(request);
        return executeGetBlock(request);
    }
<p>
Returns a block object at a specified address in a journal. Also returns a proof of the specified block for
verification if <code>DigestTipAddress</code> is provided.
</p>
<p>
For information about the data contents in a block, see <a
href="https://docs.aws.amazon.com/qldb/latest/developerguide/journal-contents.html">Journal contents</a> in the
<i>Amazon QLDB Developer Guide</i>.
</p>
<p>
If the specified ledger doesn't exist or is in <code>DELETING</code> status, then throws
<code>ResourceNotFoundException</code>.
</p>
<p>
If the specified ledger is in <code>CREATING</code> status, then throws
<code>ResourcePreconditionNotMetException</code>.
</p>
<p>
If no block exists with the specified address, then throws <code>InvalidParameterException</code>.
</p>

@param getBlockRequest
@return Result of the GetBlock operation returned by the service.
@throws InvalidParameterException
        One or more parameters in the request aren't valid.
@throws ResourceNotFoundException
        The specified resource doesn't exist.
@throws ResourcePreconditionNotMetException
        The operation failed because a condition wasn't satisfied in advance.
@sample AmazonQLDB.GetBlock
@see <a href="http://docs.aws.amazon.com/goto/WebAPI/qldb-2019-01-02/GetBlock" target="_top">AWS API
     Documentation</a>
aws-java-sdk-qldb/src/main/java/com/amazonaws/services/qldb/AmazonQLDBClient.java