Fixes #1541 [java] InvalidSlf4jMessageFormat: False positive with placeholder and exception

pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/logging/InvalidSlf4jMessageFormatRule.java

@@ -93,7 +93,10 @@ public class InvalidSlf4jMessageFormatRule extends AbstractJavaRule {
         }
 
         // Remove throwable param, since it is shown separately.
+        // But only, if it is not used as a placeholder argument
+        if (params.size() > expectedArguments) {
             removeThrowableParam(params);
+        }
 
         if (params.size() < expectedArguments) {
             addViolationWithMessage(data, node, "Missing arguments," + getExpectedMessage(params, expectedArguments));

pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/loggingjava/xml/InvalidSlf4jMessageFormat.xml

@@ -152,6 +152,27 @@ public class InvalidSlf4jExceptionTest {
             throw e;
         }
     }
+}
+        ]]></code>
+    </test-code>
+
+    <test-code>
+        <description>#1541 [java] InvalidSlf4jMessageFormat: False positive with placeholder and exception</description>
+        <expected-problems>0</expected-problems>
+        <code><![CDATA[
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class InvalidSl4jExceptionBug1541 {
+    private static final Logger log = LoggerFactory.getLogger(InvalidSl4jExceptionBug1541.class);
+
+    public static void main(String[] args) {
+        try {
+            // ...
+        } catch (Exception e) {
+            log.error("Arg1 = {}. Exception: {}", "arg1Value", e);
+        }
+    }
 }
         ]]></code>
     </test-code>

src/site/markdown/overview/changelog.md

@@ -51,6 +51,8 @@
     *   [#1545](https://sourceforge.net/p/pmd/bugs/1545/): \[java] Symbol Table fails to resolve inner classes
 *   java-imports
     *   [#1546](https://sourceforge.net/p/pmd/bugs/1546/): \[java] UnnecessaryFullyQualifiedNameRule doesn't take into consideration conflict resolution
+*   java-logging-java
+    *   [#1541](https://sourceforge.net/p/pmd/bugs/1541/): \[java] InvalidSlf4jMessageFormat: False positive with placeholder and exception
 *   XML
     *   [#1518](https://sourceforge.net/p/pmd/bugs/1518/): \[xml] Error while processing xml file with ".webapp" in the file or directory name
 *   psql