One subtask of the JDK migration from the legacy bug tracking system to JIRA was reclassifying bugs from a three-level taxonomy in the legacy system, (product, category, subcategory), to a fundamentally two-level scheme in our customized JIRA instance, (component, subcomponent). In the JDK JIRA system, there is technically a third project-level classification, but by design a large majority of JDK-related bugs were migrated into a single "JDK" project. In the end, over 450 legacy subcategories were simplified into about 120 subcomponents in JIRA. The 120 subcomponents are distributed among 17 components. A rule of thumb used was that a subcategory had to have at least 50 bugs in it for it to be retained.

Below is a listing the component / subcomponent classification of the JDK JIRA project along with some notes and guidance on which OpenJDK email addresses cover different areas. Eventually, a separate incidents project to host new issues filed at bugs.sun.com will use a slightly simplified version of this scheme.

The preponderance of bugs and subcomponents for the JDK are in library-related areas, with components named foo-libs and subcomponents primarily named after packages. While there was an overall condensation of subcomponents in the migration, in some cases long-standing informal divisions in core libraries based on naming conventions in the description were promoted to formal subcomponents. For example, hundreds of bugs in the java.util subcomponent whose descriptions started with "(coll)" were moved into java.util:collections. Likewise, java.lang bugs starting with "(reflect)" and "(proxy)" were moved into java.lang:reflect.

• client-libs (Predominantly discussed on 2d-dev and awt-dev and swing-dev.)
  • 2d
  • demo
  • java.awt
  • java.awt:i18n
  • java.beans (See beans-dev.)
  • javax.accessibility
  • javax.imageio
  • javax.sound (See sound-dev.)
  • javax.swing
• core-libs (See core-libs-dev.)
  • java.io
  • java.io:serialization
  • java.lang
  • java.lang.invoke
  • java.lang:class_loading
  • java.lang:reflect
  • java.math
  • java.net
  • java.nio (Discussed on nio-dev.)
  • java.nio.charsets
  • java.rmi
  • java.sql
  • java.sql:bridge
  • java.text
  • java.util
  • java.util.concurrent
  • java.util.jar
  • java.util.logging
  • java.util.regex
  • java.util:collections
  • java.util:i18n
  • javax.annotation.processing
  • javax.lang.model
  • javax.naming (JNDI)
  • javax.script
  • javax.script:javascript
  • javax.sql
  • org.openjdk.jigsaw (See jigsaw-dev.)
• security-libs (See security-dev.)
  • java.security
  • javax.crypto (JCE: includes SunJCE/MSCAPI/UCRYPTO/ECC)
  • javax.crypto:pkcs11 (JCE: PKCS11 only)
  • javax.net.ssl (JSSE, includes javax.security.cert)
  • javax.security
  • javax.smartcardio
  • javax.xml.crypto
  • org.ietf.jgss
  • org.ietf.jgss:krb5
• other-libs
  • corba
  • corba:idl
  • corba:orb
  • corba:rmi-iiop
  • javadb
  • other (When no other subcomponent is more appropriate; use judiciously.)

Most of the subcomponents in the xml component are related to jaxp.

• xml
  • jax-ws
  • jaxb
  • javax.xml.parsers (JAXP)
  • javax.xml.stream (JAXP)
  • javax.xml.transform (JAXP)
  • javax.xml.validation (JAXP)
  • javax.xml.xpath (JAXP)
  • jaxp (JAXP)
  • org.w3c.dom (JAXP)
  • org.xml.sax (JAXP)

For OpenJDK, most JVM-related bugs are connected to the HotSpot Java virtual machine.

• hotspot (See hotspot-dev.)
  • build
  • compiler (See hotspot-compiler-dev.)
  • gc (garbage collection, see hotspot-gc-dev.)
  • jfr (Java Flight Recorder)
  • jni (Java Native Interface)
  • jvmti (JVM Tool Interface)
  • mvm (Multi-Tasking Virtual Machine)
  • runtime (See hotspot-runtime-dev.)
  • svc (Servicability)
  • test
• core-svc (See serviceability-dev.)
  • debugger
  • java.lang.instrument
  • java.lang.management
  • javax.management
  • tools

The full JDK bug database contains entries related to legacy virtual machines that predate HotSpot as well as retired APIs.

• vm-legacy
  • jit (Sun Exact VM)
  • jit_symantec (Symantec VM, before Exact VM)
  • jvmdi (JVM Debug Interface )
  • jvmpi (JVM Profiler Interface )
  • runtime (Exact VM Runtime)

Notable command line tools in the $JDK/bin directory have corresponding subcomponents.

• tools
  • appletviewer
  • apt (See compiler-dev.)
  • hprof
  • jar
  • javac (See compiler-dev.)
  • javadoc(tool) (See compiler-dev.)
  • javah (See compiler-dev.)
  • javap (See compiler-dev.)
  • jconsole
  • launcher
  • updaters (Timezone updaters, etc.)
  • visualvm

Some aspects of JDK infrastructure directly affect JDK Hg repositories, but other do not.

• infrastructure
  • build (See build-dev and build-infra-dev.)
  • licensing (Covers updates to the third party readme, licenses, and similar files.)
  • release_eng (Release engineering)
  • staging (Staging of web pages related to JDK releases.)

The specification subcomponent encompasses the formal language and virtual machine specifications.

• specification
  • language (The Java Language Specification)
  • vm (The Java Virtual Machine Specification)

The code for the deploy and install areas is not currently included in OpenJDK.

• deploy
  • deployment_toolkit
  • plugin
  • webstart
• install
  • auto_update
  • install
  • servicetags

In the JDK, there are a number of cross-cutting concerns whose organization is essentially orthogonal to other areas. Since these areas generally have dedicated teams working on them, it is easier to find bugs of interest if these bugs are grouped first by their cross-cutting component rather than by the affected technology.

• docs
  • doclet
  • guides
  • hotspot
  • release_notes
  • tools
  • tutorial
• embedded
  • build
  • hotspot
  • libraries
• globalization
  • locale-data
  • translation
• performance
  • hotspot
  • libraries

The list of subcomponents will no doubt grow over time, but my inclination is to resist that growth since the addition of each subcomponent makes the system as a whole more complicated and harder to use.

When the system gets closer to being externalized, I plan to post more blog entries describing recommended use of various custom fields in the JDK project.