Merge branch 'pr-2773' into master

[java] issue-2738: Adding null check to avoid npe when switch case is default #2773

docs/pages/release_notes.md

@@ -17,7 +17,8 @@ This is a {{ site.pmd.release_type }} release.
 ### Fixed Issues
 
 * pmd-java
-   * [#2708](https://github.com/pmd/pmd/pull/2708): \[java] False positive FinalFieldCouldBeStatic when using lombok Builder.Default
+    * [#2708](https://github.com/pmd/pmd/issues/2708): \[java] False positive FinalFieldCouldBeStatic when using lombok Builder.Default
+    * [#2738](https://github.com/pmd/pmd/issues/2738): \[java] Custom rule with @ExhaustiveEnumSwitch throws NPE
 
 
 ### API Changes
@@ -25,6 +26,7 @@ This is a {{ site.pmd.release_type }} release.
 ### External Contributions
 
 * [#2747](https://github.com/pmd/pmd/pull/2747): \[java] Don't trigger FinalFieldCouldBeStatic when field is annotated with lombok @Builder.Default - [Ollie Abbey](https://github.com/ollieabbey)
+* [#2773](https://github.com/pmd/pmd/pull/2773): \[java] issue-2738: Adding null check to avoid npe when switch case is default - [Nimit Patel](https://github.com/nimit-patel)
 
 {% endtocmaker %}
 

pmd-java/src/main/java/net/sourceforge/pmd/lang/java/ast/ASTSwitchStatement.java

@@ -86,7 +86,10 @@ public class ASTSwitchStatement extends AbstractJavaNode implements Iterable<AST
                 // since this is an enum switch, the labels are necessarily
                 // the simple name of some enum constant.
 
-                constantNames.remove(label.getFirstDescendantOfType(ASTName.class).getImage());
+                // descendant can be null for default case
+                if (label.getFirstDescendantOfType(ASTName.class) != null) {
+                    constantNames.remove(label.getFirstDescendantOfType(ASTName.class).getImage());
+                }
 
             }
 

pmd-java/src/test/java/net/sourceforge/pmd/lang/java/ast/ASTSwitchStatementTest.java

@@ -0,0 +1,21 @@
+/*
+ * BSD-style license; for more info see http://pmd.sourceforge.net/license.html
+ */
+
+package net.sourceforge.pmd.lang.java.ast;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class ASTSwitchStatementTest extends BaseParserTest {
+
+    @Test
+    public void exhaustiveEnumSwitchWithDefault() {
+        ASTSwitchStatement switchStatement = getNodes(ASTSwitchStatement.class,
+                "import java.nio.file.AccessMode; class Foo { void bar(AccessMode m) {"
+                + "switch (m) { case READ: break; default: break; } } }")
+                .get(0);
+        Assert.assertFalse(switchStatement.isExhaustiveEnumSwitch()); // this should not throw a NPE...
+        Assert.assertTrue(switchStatement.hasDefaultCase());
+    }
+}