| org.apache.logging.log4j.core | Implementation of Log4j 2. | 
| org.apache.logging.log4j.core.appender | Log4j 2 Appenders. | 
| org.apache.logging.log4j.core.appender.db | The classes in this package and sub packages provide appenders for various types of databases and methods for
 accessing databases. | 
| org.apache.logging.log4j.core.appender.db.jdbc | The JDBC Appender supports writing log events to a relational database using standard JDBC connections. | 
| org.apache.logging.log4j.core.appender.mom | Message oriented middleware appenders. | 
| org.apache.logging.log4j.core.appender.mom.jeromq | Classes and interfaces for ZeroMQ/JeroMQ support. | 
| org.apache.logging.log4j.core.appender.mom.kafka | Classes and interfaces for Kafka appender support. | 
| org.apache.logging.log4j.core.appender.nosql | The NoSQL Appender supports writing log events to NoSQL databases. | 
| org.apache.logging.log4j.core.appender.rewrite | Apache Flume Appender. | 
| org.apache.logging.log4j.core.appender.rolling | Rolling File Appender and support classes. | 
| org.apache.logging.log4j.core.appender.rolling.action | Support classes for the Rolling File Appender. | 
| org.apache.logging.log4j.core.appender.routing | Apache Flume Appender. | 
| org.apache.logging.log4j.core.async | Provides Asynchronous Logger classes and interfaces for low-latency logging. | 
| org.apache.logging.log4j.core.config | Configuration of Log4j 2. | 
| org.apache.logging.log4j.core.config.arbiters |  | 
| org.apache.logging.log4j.core.config.builder.api | Configuration Builder API for programmatically configuring Log4j. | 
| org.apache.logging.log4j.core.config.builder.impl | Configuration Builder Implementation. | 
| org.apache.logging.log4j.core.config.composite | Support for composite configurations. | 
| org.apache.logging.log4j.core.config.json | Classes and interfaces supporting configuration of Log4j 2 with JSON. | 
| org.apache.logging.log4j.core.config.plugins | Annotations for Log4j 2 plugins. | 
| org.apache.logging.log4j.core.config.plugins.convert | TypeConverter plugins for converter strings into various types. | 
| org.apache.logging.log4j.core.config.plugins.processor | Java annotation processor for pre-scanning Log4j 2 plugins. | 
| org.apache.logging.log4j.core.config.plugins.util | Utility and manager classes for Log4j 2 plugins. | 
| org.apache.logging.log4j.core.config.plugins.validation | Constraint validators for plugin factory methods. | 
| org.apache.logging.log4j.core.config.plugins.validation.constraints | Validation annotations. | 
| org.apache.logging.log4j.core.config.plugins.validation.validators | ConstraintValidator implementations for the constraint annotations. | 
| org.apache.logging.log4j.core.config.plugins.visitors | Visitor classes for extracting values from a Configuration or Node corresponding to a plugin annotation. | 
| org.apache.logging.log4j.core.config.properties | Configuration using Properties files. | 
| org.apache.logging.log4j.core.config.status |  | 
| org.apache.logging.log4j.core.config.xml | Classes and interfaces supporting configuration of Log4j 2 with XML. | 
| org.apache.logging.log4j.core.config.yaml | Classes and interfaces supporting configuration of Log4j 2 with YAML. | 
| org.apache.logging.log4j.core.filter | Log4j 2 Filter support. | 
| org.apache.logging.log4j.core.filter.mutable |  | 
| org.apache.logging.log4j.core.impl | Log4j 2 private implementation classes. | 
| org.apache.logging.log4j.core.jackson | Classes and interfaces for serializing and deserializing Log4j 2 log events to XML and JSON using the Jackson
 library. | 
| org.apache.logging.log4j.core.jmx | Log4j 2 JMX support. | 
| org.apache.logging.log4j.core.layout | Log4j 2 Layout support. | 
| org.apache.logging.log4j.core.layout.internal |  | 
| org.apache.logging.log4j.core.lookup | Log4j 2 Lookups. | 
| org.apache.logging.log4j.core.message |  | 
| org.apache.logging.log4j.core.net | Log4j 2 network support. | 
| org.apache.logging.log4j.core.net.ssl | Log4j 2 SSL support | 
| org.apache.logging.log4j.core.osgi | Collection of OSGi-specific classes for bundles. | 
| org.apache.logging.log4j.core.parser | Parsers for the output of various layouts. | 
| org.apache.logging.log4j.core.pattern | Provides classes implementing format specifiers in conversion patterns. | 
| org.apache.logging.log4j.core.script | Log4j 2 Script support. | 
| org.apache.logging.log4j.core.selector | Log4j 2 Context Selectors. | 
| org.apache.logging.log4j.core.time |  | 
| org.apache.logging.log4j.core.time.internal |  | 
| org.apache.logging.log4j.core.tools | Log4j 2 command line tools. | 
| org.apache.logging.log4j.core.tools.picocli |  | 
| org.apache.logging.log4j.core.util | Log4j 2 helper classes. | 
| org.apache.logging.log4j.core.util.datetime | Log4j 2 date formatting classes. | 
| org.apache.logging.log4j.core.util.internal |  |