apache · stankiewicz · Mar 4, 2026 · Mar 4, 2026 · Mar 9, 2026 · Mar 10, 2026
diff --git a/buildSrc/src/main/groovy/org/apache/beam/gradle/BeamModulePlugin.groovy b/buildSrc/src/main/groovy/org/apache/beam/gradle/BeamModulePlugin.groovy
@@ -1555,7 +1555,6 @@ class BeamModulePlugin implements Plugin<Project> {
             "MixedMutabilityReturnType",
             "PreferJavaTimeOverload",
             "NonCanonicalType",
-            "Slf4jFormatShouldBeConst",
             "Slf4jSignOnlyFormat",
             "StaticAssignmentInConstructor",
             "ThreadPriorityCheck",

diff --git a/examples/java/sql/src/main/java/org/apache/beam/examples/SchemaTransformExample.java b/examples/java/sql/src/main/java/org/apache/beam/examples/SchemaTransformExample.java
@@ -102,7 +102,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/sql/src/main/java/org/apache/beam/examples/SqlTransformExample.java b/examples/java/sql/src/main/java/org/apache/beam/examples/SqlTransformExample.java
@@ -96,7 +96,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/ApproximateQuantilesExample.java b/examples/java/src/main/java/org/apache/beam/examples/ApproximateQuantilesExample.java
@@ -71,7 +71,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/CoCombineTransformExample.java b/examples/java/src/main/java/org/apache/beam/examples/CoCombineTransformExample.java
@@ -211,7 +211,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/CoGroupByKeyExample.java b/examples/java/src/main/java/org/apache/beam/examples/CoGroupByKeyExample.java
@@ -85,7 +85,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/CombineExample.java b/examples/java/src/main/java/org/apache/beam/examples/CombineExample.java
@@ -69,7 +69,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/CountExample.java b/examples/java/src/main/java/org/apache/beam/examples/CountExample.java
@@ -64,7 +64,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/CountPerKeyExample.java b/examples/java/src/main/java/org/apache/beam/examples/CountPerKeyExample.java
@@ -68,7 +68,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/CreateExample.java b/examples/java/src/main/java/org/apache/beam/examples/CreateExample.java
@@ -80,7 +80,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/DebuggingWordCount.java b/examples/java/src/main/java/org/apache/beam/examples/DebuggingWordCount.java
@@ -119,14 +119,14 @@ public void processElement(ProcessContext c) {
       if (filter.matcher(c.element().getKey()).matches()) {
         // Log at the "DEBUG" level each element that we match. When executing this pipeline
         // these log lines will appear only if the log level is set to "DEBUG" or lower.
-        LOG.debug("Matched: " + c.element().getKey());
+        LOG.debug("Matched: {}", c.element().getKey());
         matchedWords.inc();
         c.output(c.element());
       } else {
         // Log at the "TRACE" level each element that is not matched. Different log levels
         // can be used to control the verbosity of logging providing an effective mechanism
         // to filter less important information.
-        LOG.trace("Did not match: " + c.element().getKey());
+        LOG.trace("Did not match: {}", c.element().getKey());
         unmatchedWords.inc();
       }
     }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/DistinctExample.java b/examples/java/src/main/java/org/apache/beam/examples/DistinctExample.java
@@ -69,7 +69,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/FlatMapElementsExample.java b/examples/java/src/main/java/org/apache/beam/examples/FlatMapElementsExample.java
@@ -79,7 +79,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/GroupIntoBatchesExample.java b/examples/java/src/main/java/org/apache/beam/examples/GroupIntoBatchesExample.java
@@ -75,7 +75,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/KeysExample.java b/examples/java/src/main/java/org/apache/beam/examples/KeysExample.java
@@ -71,7 +71,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/KvSwapExample.java b/examples/java/src/main/java/org/apache/beam/examples/KvSwapExample.java
@@ -70,7 +70,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/LatestExample.java b/examples/java/src/main/java/org/apache/beam/examples/LatestExample.java
@@ -85,7 +85,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/MapElementsExample.java b/examples/java/src/main/java/org/apache/beam/examples/MapElementsExample.java
@@ -77,7 +77,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/MaxExample.java b/examples/java/src/main/java/org/apache/beam/examples/MaxExample.java
@@ -64,7 +64,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/MaxPerKeyExample.java b/examples/java/src/main/java/org/apache/beam/examples/MaxPerKeyExample.java
@@ -68,7 +68,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/MeanExample.java b/examples/java/src/main/java/org/apache/beam/examples/MeanExample.java
@@ -64,7 +64,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/MeanPerKeyExample.java b/examples/java/src/main/java/org/apache/beam/examples/MeanPerKeyExample.java
@@ -68,7 +68,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/MinExample.java b/examples/java/src/main/java/org/apache/beam/examples/MinExample.java
@@ -64,7 +64,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/MinPerKeyExample.java b/examples/java/src/main/java/org/apache/beam/examples/MinPerKeyExample.java
@@ -68,7 +68,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("LogOutput: {} {}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/PartitionExample.java b/examples/java/src/main/java/org/apache/beam/examples/PartitionExample.java
@@ -193,7 +193,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/RateLimiterSimple.java b/examples/java/src/main/java/org/apache/beam/examples/RateLimiterSimple.java
@@ -106,7 +106,7 @@ public void processElement(ProcessContext c) throws Exception {
       }
 
       // Simulate external API call
-      LOG.info("Processing: " + element);
+      LOG.info("Processing: {}", element);
       Thread.sleep(100);
       c.output("Processed: " + element);
     }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/RegexExample.java b/examples/java/src/main/java/org/apache/beam/examples/RegexExample.java
@@ -76,7 +76,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/SampleExample.java b/examples/java/src/main/java/org/apache/beam/examples/SampleExample.java
@@ -77,7 +77,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/SumExample.java b/examples/java/src/main/java/org/apache/beam/examples/SumExample.java
@@ -64,7 +64,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/SumPerKeyExample.java b/examples/java/src/main/java/org/apache/beam/examples/SumPerKeyExample.java
@@ -68,7 +68,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/ToStringExample.java b/examples/java/src/main/java/org/apache/beam/examples/ToStringExample.java
@@ -75,7 +75,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/TopExample.java b/examples/java/src/main/java/org/apache/beam/examples/TopExample.java
@@ -65,7 +65,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/ValuesExample.java b/examples/java/src/main/java/org/apache/beam/examples/ValuesExample.java
@@ -71,7 +71,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/ViewExample.java b/examples/java/src/main/java/org/apache/beam/examples/ViewExample.java
@@ -113,7 +113,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/WindowExample.java b/examples/java/src/main/java/org/apache/beam/examples/WindowExample.java
@@ -88,7 +88,7 @@ public LogOutput(String prefix) {
 
     @ProcessElement
     public void processElement(ProcessContext c) throws Exception {
-      LOG.info(prefix + c.element());
+      LOG.info("{}{}", prefix, c.element());
       c.output(c.element());
     }
   }

diff --git a/...src/main/java/org/apache/beam/examples/complete/datatokenization/utils/CsvConverters.java b/...src/main/java/org/apache/beam/examples/complete/datatokenization/utils/CsvConverters.java
@@ -130,7 +130,7 @@ static String buildJsonString(
             break;
 
           default:
-            LOG.error("Invalid data type, got: " + type);
+            LOG.error("Invalid data type, got: {}", type);
             throw new RuntimeException("Invalid data type, got: " + type);
         }
       }

diff --git a/.../src/main/java/org/apache/beam/examples/complete/datatokenization/utils/SchemasUtils.java b/.../src/main/java/org/apache/beam/examples/complete/datatokenization/utils/SchemasUtils.java
@@ -73,7 +73,7 @@ public SchemasUtils(String path, Charset encoding) throws IOException {
       byte[] encoded = Files.readAllBytes(Paths.get(path));
       parseJson(new String(encoded, encoding));
     }
-    LOG.info("Extracted schema: " + bigQuerySchema.toPrettyString());
+    LOG.info("Extracted schema: {}", bigQuerySchema.toPrettyString());
   }
 
   public TableSchema getBigQuerySchema() {
@@ -156,7 +156,7 @@ public static String getGcsFileAsString(String filePath) {
       return CharStreams.toString(reader);
 
     } catch (IOException ioe) {
-      LOG.error("File system i/o error: " + ioe.getMessage());
+      LOG.error("File system i/o error", ioe);
       throw new RuntimeException(ioe);
     }
   }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/complete/game/GameStats.java b/examples/java/src/main/java/org/apache/beam/examples/complete/game/GameStats.java
@@ -130,12 +130,10 @@ public void processElement(ProcessContext c) {
                           Double gmc = c.sideInput(globalMeanScore);
                           if (score > (gmc * SCORE_WEIGHT)) {
                             LOG.info(
-                                "user "
-                                    + c.element().getKey()
-                                    + " spammer score "
-                                    + score
-                                    + " with mean "
-                                    + gmc);
+                                "user {} spammer score {} with mean {}",
+                                c.element().getKey(),
+                                score,
+                                gmc);
                             numSpammerUsers.inc();
                             c.output(c.element());
                           }

diff --git a/examples/java/src/main/java/org/apache/beam/examples/complete/game/UserScore.java b/examples/java/src/main/java/org/apache/beam/examples/complete/game/UserScore.java
@@ -172,7 +172,7 @@ public void processElement(ProcessContext c) {
         c.output(gInfo);
       } catch (ArrayIndexOutOfBoundsException | NumberFormatException e) {
         numParseErrors.inc();
-        LOG.info("Parse error on " + c.element() + ", " + e.getMessage());
+        LOG.info("Parse error on {}", c.element(), e);
       }
     }
   }

diff --git a/...les/java/src/main/java/org/apache/beam/examples/complete/kafkatopubsub/KafkaToPubsub.java b/...les/java/src/main/java/org/apache/beam/examples/complete/kafkatopubsub/KafkaToPubsub.java
@@ -199,12 +199,10 @@ public static PipelineResult run(Pipeline pipeline, KafkaToPubsubOptions options
         "bootstrapServers cannot be an empty string.");
 
     LOG.info(
-        "Starting Kafka-To-PubSub pipeline with parameters bootstrap servers:"
-            + options.getBootstrapServers()
-            + " input topics: "
-            + options.getInputTopics()
-            + " output pubsub topic: "
-            + options.getOutputTopic());
+        "Starting Kafka-To-PubSub pipeline with parameters bootstrap servers:{} input topics: {} output pubsub topic: {}",
+        options.getBootstrapServers(),
+        options.getInputTopics(),
+        options.getOutputTopic());
 
     /*
      * Steps: