Hi Akiko,
You can look at the way our
sample apps does to get reports to understand how this is done. For example, using the Java client library, you can use our
DownloadCriteriaReport class to download any reports in general.
In your case, change
this to -
reportDefinition.setReportType(ReportDefinitionReportType.CAMPAIGN_PERFORMANCE_REPORT);
This would give you the Campaign Performance Report, Next you need to add the required ImpressionReach parameter. This is done
here -
Selector selector = new Selector();
selector.getFields().addAll(Lists.newArrayList("ImpressionReach", others...));
This would download your Campaign Performance Report and include the Unique Viewers by Cookie parameter (ImpressionReach).