Add BND configuration for log4j-core

The following packages are no longer exported:

 *  org.apache.logging.log4j.core.layout.internal
 *  org.apache.logging.log4j.core.message
 *  org.apache.logging.log4j.core.time.internal
 *  org.apache.logging.log4j.core.tools.picocli
 *  org.apache.logging.log4j.core.util.internal

A new JPMS module is generated, which sets the following Java modules as
optional:
 *  java.compiler,
 *  java.logging,
 *  java.naming,
 *  java.sql.

log4j-core/pom.xml

@@ -33,6 +33,43 @@
     <javadoc.skip>false</javadoc.skip>
     <!-- TODO: fix errors an reenable SpotBugs -->
     <spotbugs.skip>true</spotbugs.skip>
+
+    <!--
+      ~ OSGi and JPMS options
+      -->
+    <bnd-multi-release>true</bnd-multi-release>
+    <bnd-extra-package-options>
+      <!-- External optional dependencies -->
+      com.conversantmedia.util.concurrent;resolution:=optional;
+      com.fasterxml.jackson.*;resolution:=optional,
+      com.lmax.disruptor.*;resolution:=optional,
+      javax.activation;resolution:=optional,
+      javax.jms;version="[1.1,3)";resolution:=optional,
+      javax.mail.*;version="[1.6,2)";resolution:=optional,
+      org.apache.commons.compress.*;resolution:=optional,
+      org.apache.commons.csv;resolution:=optional,
+      org.apache.kafka.*;resolution:=optional,
+      org.codehaus.stax2;resolution:=optional,
+      org.fusesource.jansi;resolution:=optional,
+      org.jctools.*;resolution:=optional,
+      org.zeromq;resolution:=optional,
+      <!-- `java.compiler` is optional -->
+      javax.annotation.processing;resolution:=optional,
+      javax.lang.model.*;resolution:=optional,
+      javax.tools;resolution:=optional,
+      <!-- `java.sql`, which depends on `java.logging` is optional -->
+      javax.sql;resolution:=optional,
+      java.util.logging;resolution:=optional,
+      <!-- `java.naming` is optional -->
+      javax.naming;resolution:=optional
+    </bnd-extra-package-options>
+    <bnd-extra-module-options>
+      <!-- OSGI is optional in JPMS -->
+      org.osgi.core;static=true,
+      <!-- BND seems to always add `java.logging` (dependency of `java.sql`) -->
+      java.logging;static=true,
+      java.sql;static=true
+    </bnd-extra-module-options>
   </properties>
   <dependencies>
     <dependency>

log4j-core/src/main/java/org/apache/logging/log4j/core/appender/db/jdbc/package-info.java

@@ -18,4 +18,7 @@
  * The JDBC Appender supports writing log events to a relational database using standard JDBC connections. You will need
  * a JDBC driver on your classpath for the database you wish to log to.
  */
+@Export
 package org.apache.logging.log4j.core.appender.db.jdbc;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/appender/db/package-info.java

@@ -18,4 +18,7 @@
  * The classes in this package and sub packages provide appenders for various types of databases and methods for
  * accessing databases.
  */
+@Export
 package org.apache.logging.log4j.core.appender.db;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/appender/mom/jeromq/package-info.java

@@ -20,4 +20,7 @@
  *
  * @since 2.4
  */
+@Export
 package org.apache.logging.log4j.core.appender.mom.jeromq;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/appender/mom/kafka/package-info.java

@@ -20,4 +20,7 @@
  *
  * @since 2.4
  */
+@Export
 package org.apache.logging.log4j.core.appender.mom.kafka;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/appender/mom/package-info.java

@@ -20,4 +20,7 @@
  *
  * @since 2.1
  */
+@Export
 package org.apache.logging.log4j.core.appender.mom;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/appender/nosql/package-info.java

@@ -21,4 +21,7 @@
  * {@link org.apache.logging.log4j.core.appender.nosql.NoSqlConnection NoSqlConnection}, and
  * {@link org.apache.logging.log4j.core.appender.nosql.NoSqlProvider NoSqlProvider}.
  */
+@Export
 package org.apache.logging.log4j.core.appender.nosql;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/appender/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Log4j 2 Appenders.
  */
+@Export
 package org.apache.logging.log4j.core.appender;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rewrite/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Apache Flume Appender. Requires the user specifically include Flume and its dependencies.
  */
+@Export
 package org.apache.logging.log4j.core.appender.rewrite;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/action/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Support classes for the Rolling File Appender.
  */
+@Export
 package org.apache.logging.log4j.core.appender.rolling.action;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Rolling File Appender and support classes.
  */
+@Export
 package org.apache.logging.log4j.core.appender.rolling;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/appender/routing/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Apache Flume Appender. Requires the user specifically include Flume and its dependencies.
  */
+@Export
 package org.apache.logging.log4j.core.appender.routing;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/async/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Provides Asynchronous Logger classes and interfaces for low-latency logging.
  */
+@Export
 package org.apache.logging.log4j.core.async;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/arbiters/package-info.java

@@ -0,0 +1,20 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under 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 KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+@Export
+package org.apache.logging.log4j.core.config.arbiters;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/builder/api/package-info.java

@@ -19,4 +19,7 @@
  *
  * @since 2.4
  */
+@Export
 package org.apache.logging.log4j.core.config.builder.api;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/builder/impl/package-info.java

@@ -19,4 +19,7 @@
  *
  * @since 2.4
  */
+@Export
 package org.apache.logging.log4j.core.config.builder.impl;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/composite/package-info.java

@@ -18,4 +18,7 @@
 /**
  * Support for composite configurations.
  */
+@Export
 package org.apache.logging.log4j.core.config.composite;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/json/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Classes and interfaces supporting configuration of Log4j 2 with JSON.
  */
+@Export
 package org.apache.logging.log4j.core.config.json;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Configuration of Log4j 2.
  */
+@Export
 package org.apache.logging.log4j.core.config;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/convert/package-info.java

@@ -19,4 +19,7 @@
  * TypeConverter plugins for converter strings into various types. These plugins are used for parsing plugin
  * attributes in plugin factory methods.
  */
+@Export
 package org.apache.logging.log4j.core.config.plugins.convert;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/package-info.java

@@ -18,4 +18,7 @@
 /**
  * Annotations for Log4j 2 plugins.
  */
+@Export
 package org.apache.logging.log4j.core.config.plugins;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/processor/PluginProcessor.java

@@ -27,6 +27,7 @@
 
 import javax.annotation.processing.AbstractProcessor;
 import javax.annotation.processing.Messager;
+import javax.annotation.processing.Processor;
 import javax.annotation.processing.RoundEnvironment;
 import javax.annotation.processing.SupportedAnnotationTypes;
 import javax.lang.model.SourceVersion;
@@ -39,6 +40,8 @@
 import javax.tools.FileObject;
 import javax.tools.StandardLocation;
 
+import aQute.bnd.annotation.Resolution;
+import aQute.bnd.annotation.spi.ServiceProvider;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 import org.apache.logging.log4j.core.config.plugins.PluginAliases;
 import org.apache.logging.log4j.util.Strings;
@@ -48,6 +51,7 @@
 /**
  * Annotation processor for pre-scanning Log4j 2 plugins.
  */
+@ServiceProvider(value = Processor.class, resolution = Resolution.OPTIONAL)
 @SupportedAnnotationTypes("org.apache.logging.log4j.core.config.plugins.*")
 public class PluginProcessor extends AbstractProcessor {
 

log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/processor/package-info.java

@@ -19,4 +19,7 @@
  * Java annotation processor for pre-scanning Log4j 2 plugins. This is provided as an alternative to using the
  * executable {@link org.apache.logging.log4j.core.config.plugins.util.PluginManager} class in your build process.
  */
+@Export
 package org.apache.logging.log4j.core.config.plugins.processor;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/util/package-info.java

@@ -18,4 +18,7 @@
 /**
  * Utility and manager classes for Log4j 2 plugins.
  */
+@Export
 package org.apache.logging.log4j.core.config.plugins.util;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/validation/constraints/package-info.java

@@ -20,4 +20,7 @@
  *
  * @since 2.1
  */
+@Export
 package org.apache.logging.log4j.core.config.plugins.validation.constraints;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/validation/package-info.java

@@ -20,4 +20,7 @@
  *
  * @since 2.1
  */
+@Export
 package org.apache.logging.log4j.core.config.plugins.validation;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/validation/validators/package-info.java

@@ -20,4 +20,7 @@
  *
  * @since 2.1
  */
+@Export
 package org.apache.logging.log4j.core.config.plugins.validation.validators;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/package-info.java

@@ -21,4 +21,7 @@
  * and the corresponding annotation must be annotated with
  * {@link org.apache.logging.log4j.core.config.plugins.PluginVisitorStrategy}.
  */
+@Export
 package org.apache.logging.log4j.core.config.plugins.visitors;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/properties/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Configuration using Properties files.
  */
+@Export
 package org.apache.logging.log4j.core.config.properties;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/status/package-info.java

@@ -18,4 +18,7 @@
 /**
  * Configuration classes for the {@link org.apache.logging.log4j.status.StatusLogger} API.
  */
+@Export
 package org.apache.logging.log4j.core.config.status;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/xml/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Classes and interfaces supporting configuration of Log4j 2 with XML.
  */
+@Export
 package org.apache.logging.log4j.core.config.xml;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/config/yaml/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Classes and interfaces supporting configuration of Log4j 2 with YAML.
  */
+@Export
 package org.apache.logging.log4j.core.config.yaml;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/filter/mutable/package-info.java

@@ -0,0 +1,20 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under 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 KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+@Export
+package org.apache.logging.log4j.core.filter.mutable;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/filter/package-info.java

@@ -21,4 +21,7 @@
  * {@linkplain org.apache.logging.log4j.core.config.plugins.Plugin#elementType() element type}
  * {@link org.apache.logging.log4j.core.Filter#ELEMENT_TYPE filter}.
  */
+@Export
 package org.apache.logging.log4j.core.filter;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/impl/Log4jProvider.java

@@ -16,11 +16,14 @@
  */
 package org.apache.logging.log4j.core.impl;
 
+import aQute.bnd.annotation.Resolution;
+import aQute.bnd.annotation.spi.ServiceProvider;
 import org.apache.logging.log4j.spi.Provider;
 
 /**
  * Binding for the Log4j API.
  */
+@ServiceProvider(value = Provider.class, resolution = Resolution.OPTIONAL)
 public class Log4jProvider extends Provider {
     public Log4jProvider() {
         super(10, "2.6.0", Log4jContextFactory.class);

log4j-core/src/main/java/org/apache/logging/log4j/core/impl/ThreadContextDataProvider.java

@@ -18,13 +18,16 @@
 
 import java.util.Map;
 
+import aQute.bnd.annotation.Resolution;
+import aQute.bnd.annotation.spi.ServiceProvider;
 import org.apache.logging.log4j.ThreadContext;
 import org.apache.logging.log4j.core.util.ContextDataProvider;
 import org.apache.logging.log4j.util.StringMap;
 
 /**
  * ContextDataProvider for ThreadContext data.
  */
+@ServiceProvider(value = ContextDataProvider.class, resolution = Resolution.OPTIONAL)
 public class ThreadContextDataProvider implements ContextDataProvider {
 
     @Override

log4j-core/src/main/java/org/apache/logging/log4j/core/impl/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Log4j 2 private implementation classes.
  */
+@Export
 package org.apache.logging.log4j.core.impl;
+
+import org.osgi.annotation.bundle.Export;

log4j-core/src/main/java/org/apache/logging/log4j/core/jackson/package-info.java

@@ -18,4 +18,7 @@
  * Classes and interfaces for serializing and deserializing Log4j 2 log events to XML and JSON using the Jackson
  * library.
  */
+@Export
 package org.apache.logging.log4j.core.jackson;
+
+import org.osgi.annotation.bundle.Export;