| java.io | Provides for system input and output through data streams, serialization and the file system. |
| java.lang | |
| java.lang.annotation | Core classes including wrappers for primitive types, classes, packages and class loaders, representations of the system, processes, threads and the core exception hierarchy. |
| java.lang.instrument | Provides services that allow Java programming language agents to instrument programs running on the JVM. |
| java.lang.management | Provides the management interface for monitoring and management of the Java virtual machine as well as the operating system on which the Java virtual machine is running. |
| java.lang.ref | Provides reference-object classes, which support a limited degree of interaction with the garbage collector. |
| java.lang.reflect | |
| java.sql | Provides the API for accessing and processing data stored in a data source (usually a relational database) using the Java TM programming language. |
| java.util | Contains the collections framework, legacy collection classes, event model, date and time facilities, internationalization, and miscellaneous utility classes (a string tokenizer, a random-number generator, and a bit array). |
| java.util.concurrent | |
| java.util.concurrent.atomic | |
| java.util.concurrent.locks | |
| java.util.jar | Provides classes for reading and writing the JAR (Java ARchive) file format, which is based on the standard ZIP file format with an optional manifest file. |
| java.util.logging | Provides the classes and interfaces of the Java TM 2 platform's core logging facilities. |
| java.util.prefs | This package allows applications to store and retrieve user and system preference and configuration data. |
| java.util.regex | Classes for matching character sequences against patterns specified by regular expressions. |
| java.util.spi | Service provider classes for the classes in the java.util package. |
| java.util.zip | Provides classes for reading and writing the standard ZIP and GZIP file formats. |