JastAdd2 was developed at Lund University by Torbjörn Ekman, Görel Hedin, and Eva Magnusson. JastAdd2 has recieved additional contributions from Emma Söderberg, Jesper Öqvist and Niklas Fors.
For additional contributors, see the change logs.
Copyright (c) 2005-2020, The JastAdd Team. All rights reserved.
JastAdd2 is covered by the modified BSD License. For the full license text see the LICENSE file.
The latest version of JastAdd2 can be found at jastadd.org.
JastAdd2 requires a Java Runtime Environment (JRE) to run, and a JDK to build. The minimum required Java version for JastAdd2 is Java SE 6.
JastAdd2 uses JavaCC, JJTree, and Apache Ant. JavaCC and JJTree are included in the source tree of JastAdd2, so the only external tools needed are Java and Ant. See licenses/javacc-BSD for the full license text.
The context-free grammar used in JastAdd is based on an example from JavaCC.
The README file for the binary distribution (README-binary-dist.md) is written
in the markup language Markdown. This file is converted to HTML using a Python
script during the build script. The Python script requires the Python-Markdown
package for Python. The Python-Markdown package can be installed using
Builds are done by using the Gradle script (
gradlew on Unix-likes,
gradlew.bat on Windows):
Build a new release (builds jar file, source- and binary zip files). Requires the release version to be specified with
> ./gradlew release -PnewVersion=2.123
Delete generated files:
> ./gradlew clean
.astJastAdd abstract syntax tree files
.jragJastAdd semantics files. Usually declarative.
.jaddJastAdd semantics files. Usually imperative.
.javaRegular Java sources
.jjtJavaCC files, using the JJTree AST-building commands.
src/javaJava source files.
JastAdd.javaThe main class. Compiles
*.jragfiles to Java files.
Configuration.javaEncapsulates JastAdd configuration options. Can be used to parse command line arguments.
JastAddTask.javaImplements an ANT task for running JastAdd, including support for most available options.
src/jastadd/JastAdd aspect and AST specifications
src/javacc/Parser specification files for JavaCC.
src/res/Version.propertiesContains the JastAdd version property string.
src/templateTemplate files for code generation.
src/gen/Generated source files.
docDocumentation html files.
reference-manual.htmlThe reference manual
release-notes.htmlThe release nodes
index.htmlFor download from the web
*.phpHelper files for browsing uploaded files on the web
tools3rd party jar files used to build build JastAdd.
LICENSEText file with the jastadd LICENSE.
release.shA script printing the commands for doing a release.
ChangeLogA textfile recording changes done to JastAdd, intended for users of JastAdd (focusing on external behavior).
ChangeLogUntil2010.txtA textfile containing cvs log messages until 2010 when the system was moved to svn.
Understanding the Implementation
Overall behavior when running JastAdd:
- First, options are read and global flags are set.
- Then, an incomplete AST is built by parsing the .ast file.
- Then, the .jrag files are parsed, and their information is weaved into the AST.
- Now, the AST is complete, and attributes can be accessed.
- Then, possible errors are printed.
- Then, target AST classes are generated.
JavaCC and its tree-building extension, JJTree, are used for parsing. They assume top classes called Node and SimpleNode. Normally, JJTree generates its own AST node subclasses, but we "fool" it to use the AST classes generated by JastAdd instead (by generating them before we run JavaCC/JJTree).
However, we let JJTree generate the AST classes for the Java code used inside equations in .jrag files. This is because these expressions are not analyzed by JastAdd. They are just unparsed at appropriate places in the generated Java code.