Merge pull request #9 from ref-humbold/argparser

CLI parser

Author: ref-humbold

.circleci/config.yml

@@ -21,13 +21,13 @@ jobs:
           command: ./ci/install_ant_junit5.sh
       - run:
           name: Download Dependencies
-          command: ant -lib ./lib resolve
+          command: ant resolve
       - run:
           name: Build
-          command: ant -lib ./lib jar
+          command: ant jar
       - run:
           name: Test
-          command: ant -lib ./lib test
+          command: ant test
       - store_test_results:
           path: ./junit/result
 

.github/workflows/build-and-test.yml

@@ -18,12 +18,12 @@ jobs:
       - name: Download Dependencies
         run: |
           export JAVA_HOME=/usr/lib/jvm/java-17-openjdk-amd64
-          ant -lib ./lib resolve
+          ant resolve
       - name: Build
         run: |
           export JAVA_HOME=/usr/lib/jvm/java-17-openjdk-amd64
-          ant -lib ./lib jar
+          ant jar
       - name: Test
         run: |
           export JAVA_HOME=/usr/lib/jvm/java-17-openjdk-amd64
-          ant -lib ./lib test
+          ant test

README.md

@@ -10,25 +10,22 @@ Interpreter of a fictional assembly-like APO language
 
 -----
 
-## Dependencies
-
-### Standard build & run
+## System requirements
 
-> *versions used by the author are in double parentheses and italic*
-
-General:
+> versions used by the author are in italics
 
 + Operating system \
-  *((Debian testing))*
+  *Debian testing*
 + [Java](https://www.oracle.com/technetwork/java/javase/overview/index.html) \
-  *((APT package `openjdk-17-jdk`, version 17 SE))*
+  *APT package `openjdk-17-jdk`, version 17 SE*
 + [Apache ANT](http://ant.apache.org/) \
-  *((APT package `ant`, version 1.10.+))*
+  *APT package `ant`, version 1.10.+*
 
-### Unit testing
+## Dependencies
 
-> libraries are automatically downloaded during build process
+> dependencies are automatically downloaded during build process
 
++ Apache Commons CLI 1.6.+
 + JUnit 5.+
 + AssertJ 3.+
 

build.xml

@@ -4,8 +4,8 @@
     <format property="date.version" pattern="yyMMdd" locale="en,GB" />
   </tstamp>
 
-  <property name="major.version" value="1" />
-  <property name="minor.version" value="2" />
+  <property name="major.version" value="2" />
+  <property name="minor.version" value="0" />
   <property name="spec.version" value="${major.version}.${minor.version}" />
   <property name="jar.version" value="${major.version}.${minor.version}.${date.version}" />
   <property name="vendor" value="Rafał Kaleta" />
@@ -18,6 +18,7 @@
   <property name="ant.output.dir" value="antBuild" />
   <property name="build.dir" value="${ant.output.dir}/bin" />
   <property name="dist.dir" value="${ant.output.dir}/dist" />
+  <property name="dist.lib.dir" value="${dist.dir}/lib" />
   <property name="junit.output.dir" value="${ant.output.dir}/junit" />
   <property name="junit.result.dir" value="${junit.output.dir}/result" />
   <property name="junit.report.dir" value="${junit.output.dir}/report" />
@@ -76,6 +77,7 @@
   <target name="jar" depends="compile"
     description="Compile source files &amp; Create executable jar">
     <jar destfile="${dist.dir}/${jar.file}" basedir="${build.dir}" excludes="**/*Test.class">
+      <zipgroupfileset dir="${ivy.lib.dir}" includes="*.jar" />
       <manifest>
         <attribute name="Built-By" value="${vendor}" />
         <attribute name="Main-Class" value="${main.package}.Interpreter" />

ivy.xml

@@ -1,6 +1,7 @@
 <ivy-module version="2.0">
   <info organisation="ref_humbold" module="apo_language" />
   <dependencies>
+    <dependency org="commons-cli" name="commons-cli" rev="1.6.+" />
     <dependency org="org.junit.jupiter" name="junit-jupiter-api" rev="5.+" />
     <dependency org="org.junit.jupiter" name="junit-jupiter-engine" rev="5.+" />
     <dependency org="org.junit.jupiter" name="junit-jupiter-params" rev="5.+" />

src/main/java/apolang/CliParser.java

@@ -0,0 +1,87 @@
+package apolang;
+
+import org.apache.commons.cli.*;
+
+class CliParser
+{
+    private final CommandLineParser parser = new DefaultParser();
+    private final Options options = new Options();
+    private final HelpFormatter helpFormatter = new HelpFormatter();
+
+    CliParser()
+    {
+        options.addOption(Option.builder("m")
+                                .longOpt("memory")
+                                .hasArg()
+                                .argName("SIZE")
+                                .type(Integer.class)
+                                .desc("Provide memory size in kB (default is 1 kB)")
+                                .build());
+        options.addOption("h", "help", false, "Display this help message and exit");
+    }
+
+    Arguments parse(String[] args)
+            throws ParseException
+    {
+        Arguments arguments = new Arguments();
+        CommandLine commandLine = parser.parse(options, args);
+        String[] remainingArgs = commandLine.getArgs();
+
+        arguments.help = commandLine.hasOption('h');
+
+        if(arguments.help)
+        {
+            return arguments;
+        }
+
+        try
+        {
+            arguments.memorySize = Integer.parseInt(commandLine.getOptionValue('m', "1"));
+        }
+        catch(NumberFormatException e)
+        {
+            throw new ParseException("Invalid memory size. %s".formatted(e.getMessage()));
+        }
+
+        if(remainingArgs.length == 0)
+        {
+            throw new ParseException("File not provided.");
+        }
+
+        arguments.filename = remainingArgs[0];
+
+        if(!arguments.filename.endsWith(".apo"))
+        {
+            throw new ParseException("Invalid file extension, should be '.apo'.");
+        }
+
+        return arguments;
+    }
+
+    void printHelp()
+    {
+        helpFormatter.printHelp("apolang [OPTIONS]... FILE", options);
+    }
+
+    static class Arguments
+    {
+        private boolean help;
+        private int memorySize;
+        private String filename;
+
+        boolean isHelp()
+        {
+            return help;
+        }
+
+        int getMemorySize()
+        {
+            return memorySize;
+        }
+
+        String getFilename()
+        {
+            return filename;
+        }
+    }
+}

src/main/java/apolang/Interpreter.java

@@ -3,52 +3,46 @@
 import java.io.IOException;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import org.apache.commons.cli.ParseException;
 
 import apolang.interpreter.Controller;
 
 public final class Interpreter
 {
+    private static final CliParser cliParser = new CliParser();
+
     public static void main(String[] args)
             throws IOException
     {
-        if(args.length == 0)
+        CliParser.Arguments arguments;
+
+        try
         {
-            System.err.println("No file specified. Execution stopped.");
-            return;
+            arguments = cliParser.parse(args);
         }
-
-        int memorySize = 1;
-        String filename = args[0];
-
-        if(args.length > 1)
+        catch(ParseException e)
         {
-            try
-            {
-                memorySize = Integer.parseInt(args[1]);
-            }
-            catch(Exception e)
-            {
-                System.err.println("Invalid memory size. Execution stopped.");
-                return;
-            }
+            System.err.printf("Error while parsing arguments:%n\t%s%n\tExecution stopped.%n",
+                              e.getMessage());
+            return;
         }
 
-        if(!filename.endsWith(".apo"))
+        if(arguments.isHelp())
         {
-            System.err.println("Wrong filename extension. Execution stopped.");
+            cliParser.printHelp();
             return;
         }
 
-        Path path = Paths.get(filename);
-        Controller controller = new Controller(memorySize, path);
+        Path path = Paths.get(arguments.getFilename());
+        Controller controller = new Controller(arguments.getMemorySize(), path);
 
         try
         {
             controller.parse();
         }
         catch(Exception e)
         {
-            System.err.printf("parser error>> %s\n\tExecution stopped.\n", e);
+            System.err.printf("parser error>> %s%n\tExecution stopped.%n", e);
             e.printStackTrace(System.err);
             return;
         }
@@ -59,7 +53,7 @@ public static void main(String[] args)
         }
         catch(Exception e)
         {
-            System.err.printf("interpreter error>> %s\n\tExecution stopped.\n", e);
+            System.err.printf("interpreter error>> %s%n\tExecution stopped.%n", e);
             e.printStackTrace(System.err);
         }
     }