Remove Avro-related code from Java SDK "core" module

CHANGES.md

@@ -57,8 +57,10 @@
 
 ## Highlights
 
-* New highly anticipated feature X added to Python SDK ([#X](https://github.com/apache/beam/issues/X)).
-* New highly anticipated feature Y added to Java SDK ([#Y](https://github.com/apache/beam/issues/Y)).
+* Previously deprecated Avro-dependent code (Beam Release 2.46.0) has been finally removed from Java SDK "core" package.
+Please, use `beam-sdks-java-extensions-avro` instead. This will allow to easily update Avro version in user code without
+potential breaking changes in Beam "core" since the Beam Avro extension already supports the latest Avro versions and
+should handle this. ([#25252](https://github.com/apache/beam/issues/25252)).
 
 ## I/Os
 
@@ -71,6 +73,10 @@
 ## Breaking Changes
 
 * X behavior was changed ([#X](https://github.com/apache/beam/issues/X)).
+* `org.apache.beam.sdk.io.CountingSource.CounterMark` uses custom `CounterMarkCoder` as a default coder since all Avro-dependent
+classes finally moved to `extensions/avro`. In case if it's still required to use `AvroCoder` for `CounterMark`, then,
+as a workaround, a copy of "old" `CountingSource` class should be placed into a project code and used directly
+([#25252](https://github.com/apache/beam/issues/25252)).
 
 ## Deprecations
 

sdks/java/core/build.gradle

@@ -36,7 +36,6 @@ applyJavaNature(
     relocate "org.antlr.v4", getJavaRelocatedPath("org.antlr.v4")
   },
 )
-applyAvroNature()
 applyAntlrNature()
 
 generateGrammarSource {
@@ -89,7 +88,6 @@ dependencies {
   shadow library.java.jackson_annotations
   shadow library.java.jackson_databind
   shadow library.java.slf4j_api
-  shadow library.java.avro
   shadow library.java.snappy_java
   shadow library.java.joda_time
   implementation enforcedPlatform(library.java.google_cloud_platform_libraries_bom)
@@ -114,7 +112,6 @@ dependencies {
   shadowTest "com.esotericsoftware.kryo:kryo:2.21"
   shadowTest library.java.quickcheck_core
   shadowTest library.java.quickcheck_generators
-  shadowTest library.java.avro_tests
   shadowTest library.java.zstd_jni
   shadowTest library.java.commons_logging
   shadowTest library.java.log4j
@@ -124,5 +121,6 @@ dependencies {
 }
 
 project.tasks.compileTestJava {
-  options.compilerArgs += ['-Xlint:-rawtypes'] // generated avro uses rawtypes without suppression
+  // TODO: fix other places with warnings in tests and delete this option
+  options.compilerArgs += ['-Xlint:-rawtypes']
 }