Rework maven code for faster calculation of path config

pom.xml

@@ -29,6 +29,7 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <lucence-version>7.5.0</lucence-version>
+        <maven-version>3.9.8</maven-version>
         <exec.mainClass>org.rascalmpl.shell.RascalShell</exec.mainClass>
         <rascal.test.memory>2</rascal.test.memory>
         <maven.compiler.release>11</maven.compiler.release>
@@ -317,9 +318,10 @@
                                 <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                                     <resource>org/rascalmpl/uri/resolvers.config</resource>
                                     <resource>io/usethesource/vallang/type/types.config </resource>
+                                    <resource>META-INF/sisu/javax.inject.Named</resource> <!-- Needed for dependency injection in MavenCli -->
                                 </transformer>
-                                <transformer implementation="org.apache.maven.plugins.shade.resource.ApacheLicenseResourceTransformer">
-                                </transformer>
+                                <transformer implementation="org.apache.maven.plugins.shade.resource.ComponentsXmlResourceTransformer"/> <!-- Needed for dependency injection in MavenCli -->
+                                <transformer implementation="org.apache.maven.plugins.shade.resource.ApacheLicenseResourceTransformer"/>
                                 <transformer implementation="org.apache.maven.plugins.shade.resource.ApacheNoticeResourceTransformer">
                                     <addHeader>false</addHeader>
                                 </transformer>
@@ -514,5 +516,30 @@
             <artifactId>icu4j</artifactId>
             <version>74.2</version>
         </dependency>
+        <dependency>
+            <groupId>org.apache.maven</groupId>
+            <artifactId>maven-embedder</artifactId>
+            <version>${maven-version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-dependency-plugin</artifactId>
+            <version>3.7.1</version>
+        </dependency>
+        <dependency> <!-- needed for maven-embedder-->
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-simple</artifactId>
+            <version>1.7.36</version>
+        </dependency>
+        <dependency> <!-- needed for maven-embedder-->
+            <groupId>org.apache.maven</groupId>
+            <artifactId>maven-compat</artifactId>
+            <version>${maven-version}</version>
+        </dependency>
+        <dependency> <!-- needed for maven-embedder-->
+            <groupId>org.apache.maven</groupId>
+            <artifactId>maven-core</artifactId>
+            <version>${maven-version}</version>
+        </dependency>
     </dependencies>
 </project>

src/org/rascalmpl/library/util/PathConfig.java

@@ -1,21 +1,25 @@
 package org.rascalmpl.library.util;
 
-import java.io.BufferedReader;
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
-import java.io.InputStreamReader;
 import java.io.StringReader;
 import java.io.StringWriter;
 import java.net.URISyntaxException;
+import java.nio.file.Files;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.Set;
+import java.util.regex.Pattern;
 
+import org.apache.maven.cli.CliRequest;
+import org.apache.maven.cli.MavenCli;
+import org.codehaus.plexus.classworlds.ClassWorld;
 import org.rascalmpl.interpreter.Configuration;
 import org.rascalmpl.interpreter.utils.RascalManifest;
 import org.rascalmpl.uri.ILogicalSourceLocationResolver;
@@ -650,83 +654,46 @@
                 return vf.list();
             }
 
-            String mvnCommand = computeMavenCommandName();
-
-            installNecessaryMavenPlugins(mvnCommand);
-
-            // Note how we try to do this "offline" using the "-o" flag
-            ProcessBuilder processBuilder = new ProcessBuilder(mvnCommand, 
-                "--batch-mode", 
-                "-o", 
-                "dependency:build-classpath",
-                "-DincludeScope=compile",
-                trustStoreFix()
-            );
-
-            processBuilder.directory(new File(manifestRoot.getPath()));
-            processBuilder.environment().put("JAVA_HOME", System.getProperty("java.home", System.getenv("JAVA_HOME")));
-
-            Process process = processBuilder.start();
+            var maven = new MavenCli();
+            var tempFile = Files.createTempFile("rascal-classpath-", ".tmp");
+
+            maven.doMain(buildRequest(new String[] {"-quiet", "-o", "dependency:build-classpath", "-DincludeScope=compile", "-Dmdep.outputFile=" + tempFile.toString()}, manifestRoot));
+
+            var foundClassPath = Files.readAllLines(tempFile).get(0);
 
-            try (BufferedReader processOutputReader = new BufferedReader(new InputStreamReader(process.getInputStream()))) {
-                return processOutputReader.lines()
-                    .filter(line -> !line.startsWith("["))
-                    .filter(line -> !line.contains("-----"))
-                    .flatMap(line -> Arrays.stream(line.split(File.pathSeparator)))
-                    .filter(fileName -> new File(fileName).exists())
-                    .map(elem -> {
-                        try {
-                            return URIUtil.createFileLocation(elem);
-                        }
-                        catch (URISyntaxException e) {
-                            return null;
-                        }
-                    })
-                    .filter(e -> e != null)
-                    .collect(vf.listWriter());
-            }
+            return Arrays.stream(foundClassPath.split(File.pathSeparator))
+                .filter(fileName -> new File(fileName).exists())
+                .map(elem -> {
+                    try {
+                        return URIUtil.createFileLocation(elem);
+                    }
+                    catch (URISyntaxException e) {
+                        return null;
+                    }
+                })
+                .filter(Objects::nonNull)
+                .collect(vf.listWriter());
         }
-        catch (IOException e) {
+        catch (IOException | RuntimeException | ReflectiveOperationException e) {
             return vf.list();
         }
     }
 
-    private static boolean isWindows() {
-        return System.getProperty("os.name").toLowerCase().contains("win");
+    private static void setField(CliRequest req, String fieldName, Object value) throws ReflectiveOperationException {
+        var field = CliRequest.class.getDeclaredField(fieldName);
+        field.setAccessible(true);
+        field.set(req, value);
     }
 
-    private static String computeMavenCommandName() {
-        if (System.getProperty("os.name", "generic").startsWith("Windows")) {
-            return "mvn.cmd";
-        }
-        else {
-            return "mvn";
-        }
-    }
-
-    private static void installNecessaryMavenPlugins(String mvnCommand) {
-        try {
-            ProcessBuilder processBuilder = new ProcessBuilder(mvnCommand, 
-                "-q", 
-                "dependency:get", 
-                "-DgroupId=org.apache.maven.plugins",
-                "-DartifactId=maven-dependency-plugin", 
-                "-Dversion=2.8",
-                trustStoreFix());
-            processBuilder.environment().put("JAVA_HOME", System.getProperty("java.home", System.getenv("JAVA_HOME")));
-
-            Process process = processBuilder.start();
-            if (process.waitFor() != 0) {
-                throw new IOException("mvn dependency:get returned non-zero");
-            } 
-        }
-        catch (IOException | InterruptedException e) {
-            System.err.println("[WARNING] Could not install exec-maven-plugin; classpath resolution may be incomplete hereafter: " + e.getMessage());
-        }
-    }
-
-    private static String trustStoreFix() {
-        return isWindows() ? WINDOWS_ROOT_TRUSTSTORE_TYPE_DEFINITION : "-Dnothing_to_see_here";
+    private static CliRequest buildRequest(String[] args, ISourceLocation manifestRoot) throws ReflectiveOperationException {
+        // we need to set a field that the default class doesn't set
+        // it's a work around around a bug in the MavenCli code
+        var cons = CliRequest.class.getDeclaredConstructor(String[].class, ClassWorld.class);
+        cons.setAccessible(true);
+        var result = cons.newInstance(args, null);
+        setField(result, "workingDirectory", new File(manifestRoot.getPath()).getPath());
+        setField(result, "multiModuleProjectDirectory", new File(manifestRoot.getPath()));
+        return result;
     }
 
     public ISourceLocation getBin() {