From 488f8c716f061fca934d539fdc7cfa0e678d4356 Mon Sep 17 00:00:00 2001
From: Andreas Dangel <andreas.dangel@pmd-code.org>
Date: Thu, 17 Feb 2022 18:52:53 +0100
Subject: [PATCH] Avoid NPE if writer is not set in AbstractRenderer.flush

---
 .../java/net/sourceforge/pmd/renderers/AbstractRenderer.java | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/renderers/AbstractRenderer.java b/pmd-core/src/main/java/net/sourceforge/pmd/renderers/AbstractRenderer.java
index 88b69d2202..ea12ba8630 100644
--- a/pmd-core/src/main/java/net/sourceforge/pmd/renderers/AbstractRenderer.java
+++ b/pmd-core/src/main/java/net/sourceforge/pmd/renderers/AbstractRenderer.java
@@ -103,6 +103,11 @@ public abstract class AbstractRenderer extends AbstractPropertySource implements
 
     @Override
     public void flush() {
+        if (writer == null) {
+            // might happen, if no writer is set. E.g. in maven-pmd-plugin's PmdCollectingRenderer
+            return;
+        }
+
         try {
             this.writer.flush();
         } catch (IOException e) {