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PicoJava

Java processor created by Sun Microsystems

Wikipedia contributorsAdapted for Fathomly · View authors
1 min read
Source updated June 16, 2026

picoJava is a microprocessor specification dedicated to native execution of Java bytecode without the need for an interpreter or just-in-time compilation. The aim is to speed bytecode execution up by up to 20 times, compared to standard Intel CPU with a Java virtual machine. GNU Compiler Collection added picoJava support in 1999 as machine definition 'pj,'. The open-source version of picoJava has been implemented in an FPGA.

01Creation

Picojava was developed by Sun Microsystems, the first version of the specification was created in 1997. This first version was never released as a product by Sun. A redesign of Picojava in 1999 would give birth to Picojava-II, which is freely available and has a rich documentation.

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Sources and credits

This article is adapted from the Wikipedia article “PicoJava”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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