JSRs: Java Specification Requests
JSR 385: Units of Measurement API 2.0
JCP version in use: 2.11
Java Specification Participation Agreement version in use: 2.0
This JSR is a major evolution of the Unit API 1.0 (JSR 363) specification. Focused on the SI System redefinition, modularity and support for Java SE 8/9 and above.
Expert Group Transparency:
Public Project Page
The following updates have been made to the original proposal:
2019.03.28: The Spec Leads moved the JSR to JCP version 2.11.
Section 1. Identification
Submitting Member: Werner Keil
Name of Contact Person: Werner Keil
E-Mail Address: werner.keil
Telephone Number: +4917636954273
Fax Number: -
Specification Lead Members:
Initial list of Contributors and Expert Group Membership:
Supporting this JSR:
Section 2: Request
2.1 Please describe the proposed Specification:
This JSR is to provide an update for the Java API for Units of Measurement (JSR 363). Proposed changes include:
See https://github.com/unitsofmeasurement/unit-api/milestone/2 for a detailed list of proposed changes and improvements
The API is targeted to the resource-constrained devices such as smart meters, medical devices, or similar and needs to be memory-efficient to run on. On the other hand it must perform to cope with incoming sensor data.
2.2 What is the target Java platform? (i.e., desktop, server, personal, embedded, card, etc.)
Java(TM) desktop, embedded and server platforms.
2.3 The Executive Committees would like to ensure JSR submitters think about how their proposed technology relates to all of the Java platform editions. Please provide details here for which platform editions are being targeted by this JSR, and how this JSR has considered the relationship with the other platform editions.
The packages are targeted at Java Embedded (SE and possible future ME) as well as IoT, Big Data or Data Analytics in the Cloud. This JSR should have few dependencies outside the packages and types defined by the CLDC.
2.4 What need of the Java community will be addressed by the proposed specification?
See 2.1 above.
2.5 Why isn't this need met by existing specifications?
See 2.1 above for Proposed redefinition of SI base units and other intended changes.
2.6 Please give a short description of the underlying technology or technologies:
2.7 Is there a proposed package name for the API Specification? (i.e., javapi.something, org.something, etc.)
The API will continue to use the javax.measure package.
2.8 Does the proposed specification have any dependencies on specific operating systems, CPUs, or I/O devices that you know of?
2.9 Are there any security issues that cannot be addressed by the current security model?
2.10 Are there any internationalization or localization issues?
There are some internationalization issues that this JSR will address:
2.11 Are there any existing specifications that might be rendered obsolete, deprecated, or in need of revision as a result of this work?
2.12 Please describe the anticipated schedule for the development of this specification.
Q1 2018: finalize expert group
2.13 Please describe the anticipated working model for the Expert Group working on developing this specification.
The primary means of communication will be email (via mailing lists firstname.lastname@example.org for EG Members and similar active contributors and email@example.com for observers and other users of the API)
2.14 Provide detailed answers to the transparency checklist, making sure to include URLs as appropriate:
The Units Of Measurement interfaces and their implementations are developed in an open source process. We intend to use the existing infrastructures:
The spec leads demonstrated responsiveness in JSR 363, which is supported by various JUGs and other Open Source communities and won the JCP Award for Most Significant JSR of 2015.
2.15 Please describe how the RI and TCK will be delivered, i.e. as part of a profile or platform edition, or stand-alone, or both. Include version information for the profile or platform in your answer.
The RI will be implemented inside the open source project 'unitsofmeasurement.github.io'. We target stand-alone releases.
2.16 Please state the rationale if previous versions are available stand-alone and you are now proposing in 2.13 to only deliver RI and TCK as part of a profile or platform edition (See sections 1.1.5 and 1.1.6 of the JCP 2 document).
2.17 Please provide a description of the business terms for the Specification, RI and TCK that will apply when this JSR is final.
2.18 Please describe the communications channel you have established for the public to observe Expert Group deliberations, provide feedback, and view archives of all Expert Group communications.
- The Expert Group business is readable on Google Groups firstname.lastname@example.org, email@example.com.
2.19 What is the URL of the Issue Tracker that the public can read, and how does the public log issues in the Issue Tracker?
2.20 Please provide the location of the publicly accessible document archive you have created for the Expert Group.
Section 3: Contributions
3.1 Please list any existing documents, specifications, or implementations that describe the technology. Please include links to the documents if they are publicly available.
JSR 363: Units of Measurement API https://jcp.org/en/jsr/detail?id=363
3.2 Explanation of how these items might be used as a starting point for the work.
These specifications will be the starting point for this work.