added preventing the shade plugin from relocating org.slf4j.Logger to *.shaded.slf4j.Logger (#1049)

Author: videnkz

CHANGELOG.asciidoc

@@ -37,6 +37,7 @@ endif::[]
 [float]
 ===== Bug fixes
 * When JAX-RS-annotated method delegates to another JAX-RS-annotated method, transaction name should include method A - {pull}1062[#1062]
+* Fixed bug that prevented an APM Error from being created when calling `org.slf4j.Logger#error` - {pull}1049[#1049]
 
 [[release-notes-1.x]]
 === Java Agent version 1.x

apm-agent-plugins/apm-error-logging-plugin/src/main/java/co/elastic/apm/agent/error/logging/Log4jLoggingInstrumentation.java

@@ -11,9 +11,9 @@
  * the Apache License, Version 2.0 (the "License"); you may
  * not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  * http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing,
  * software distributed under the License is distributed on an
  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
@@ -35,9 +35,12 @@
 
 public class Log4jLoggingInstrumentation extends AbstractLoggingInstrumentation {
 
+ // prevents the shade plugin from relocating org.slf4j.Logger to co.elastic.apm.agent.shaded.slf4j.Logger
+ private static final String SLF4J_LOGGER = "org!slf4j!Logger".replace('!', '.');
+
  @Override
  public ElementMatcher<? super TypeDescription> getTypeMatcher() {
- return hasSuperType(named("org.apache.logging.log4j.Logger")).and(not(hasSuperType(named("org.slf4j.Logger"))));
+ return hasSuperType(named("org.apache.logging.log4j.Logger")).and(not(hasSuperType(named(SLF4J_LOGGER))));
  }
 
  @Override

apm-agent-plugins/apm-error-logging-plugin/src/main/java/co/elastic/apm/agent/error/logging/Slf4jLoggingInstrumentation.java

@@ -11,9 +11,9 @@
  * the Apache License, Version 2.0 (the "License"); you may
  * not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  * http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing,
  * software distributed under the License is distributed on an
  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
@@ -35,9 +35,13 @@
 
 public class Slf4jLoggingInstrumentation extends AbstractLoggingInstrumentation {
 
+ // prevents the shade plugin from relocating org.slf4j.Logger to co.elastic.apm.agent.shaded.slf4j.Logger
+ private static final String SLF4J_LOGGER = "org!slf4j!Logger".replace('!', '.');
+
  @Override
  public ElementMatcher<? super TypeDescription> getTypeMatcher() {
- return hasSuperType(named("org.slf4j.Logger")).and(not(hasSuperType(named("org.apache.logging.log4j.Logger"))));
+ return hasSuperType(named(SLF4J_LOGGER)
+ .and(not(hasSuperType(named("org.apache.logging.log4j.Logger")))));
  }
 
  @Override

apm-agent-plugins/apm-error-logging-plugin/src/test/java/co/elastic/apm/agent/error/logging/Slf4jLoggingInstrumentationTest.java

@@ -11,9 +11,9 @@
  * the Apache License, Version 2.0 (the "License"); you may
  * not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  * http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing,
  * software distributed under the License is distributed on an
  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY