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Open the Checkstyle "Violations Overview" view (Window -> Show View -> Other -> Checkstyle -> Checkstyle violations)
Select the projects you want to check, right-click and select "Checkstyle -> Check project"
The Checkstype violations view shows you all violations
Ensure that you have to violation prior to a pull request
PMD
Open the Checkstyle "Violations Overview" view (Window -> Show View -> Other -> Checkstyle PMD -> Checkstyle violationsViolations Overview)
Select the projects you want to check, right-click and select "Checkstyle PMD -> Check project"
The Checkstype PMD violations view shows you all violations
Ensure that you have to violation prior to a pull request