Antlr is a parser generator written in Java.
Execute these commands to download atlr .jar file in /usr/local/lib directory
cd /usr/local/lib
curl -O http://www.antlr.org/download/antlr-4.5-complete.jar
add antlr4 to your class path.
export CLASSPATH=".:/usr/local/lib/antlr-4.5-complete.jar:$CLASSPATH"
create alias
alias antlr4='java -Xmx500M -cp "/usr/local/lib/antlr-4.5-complete.jar:$CLASSPATH" org.antlr.v4.Tool'
alias grun='java org.antlr.v4.runtime.misc.TestRig'
Test installation
java org.antlr.v4.Tool
ANTLR Parser Generator Version 4.5
-o ___ specify output directory where all output is generated
-lib ___ specify location of grammars, tokens files
-atn generate rule augmented transition network diagrams
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The above 3 commands (one export and two alias commands) needs to be run every time you start a new terminal. To solve this problem put the three commands in your .bashrc file like shown below.
Open the.bashrc file in any text editor
gedit ~/.bashrc
and add the three commands at the bottom of the file, Like shown in the image below
Note: bashrc is a script file that automatically executes whenever a new terminal is opened.