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pmendelskipmendelski
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Fix context scanner
1 parent 04f083a commit 4711063

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5 files changed

+426
-93
lines changed

5 files changed

+426
-93
lines changed

‎build.gradle‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -12,10 +12,10 @@ group = 'com.coditory.quark'
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description = 'Coditory Quark Context Library'
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dependencies {
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api 'org.slf4j:slf4j-api:2.0.3'
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api 'org.slf4j:slf4j-api:2.0.5'
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api 'org.jetbrains:annotations:23.0.0'
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api 'com.coditory.quark:quark-eventbus:0.0.5'
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testImplementation 'ch.qos.logback:logback-classic:1.4.4'
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testImplementation 'ch.qos.logback:logback-classic:1.4.5'
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testImplementation 'org.spockframework:spock-core:2.3-groovy-4.0'
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testImplementation 'org.skyscreamer:jsonassert:1.5.1'
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}

‎src/main/java/com/coditory/quark/context/ClassPath.java‎

Lines changed: 367 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,367 @@
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package com.coditory.quark.context;
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import org.slf4j.Logger;
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import org.slf4j.LoggerFactory;
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import java.io.File;
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import java.io.IOException;
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import java.net.MalformedURLException;
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import java.net.URISyntaxException;
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import java.net.URL;
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import java.net.URLClassLoader;
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import java.util.ArrayList;
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import java.util.Arrays;
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import java.util.Enumeration;
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import java.util.HashSet;
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import java.util.LinkedHashMap;
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import java.util.LinkedHashSet;
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import java.util.List;
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import java.util.Map;
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import java.util.Set;
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import java.util.jar.Attributes;
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import java.util.jar.JarEntry;
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import java.util.jar.JarFile;
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import java.util.jar.Manifest;
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import static java.util.Collections.unmodifiableList;
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import static java.util.Collections.unmodifiableMap;
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import static java.util.Collections.unmodifiableSet;
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import static java.util.Objects.requireNonNull;
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import static java.util.stream.Collectors.toSet;
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final class ClassPath {
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private static final Logger logger = LoggerFactory.getLogger(ClassPath.class.getName());
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private static final String CLASS_FILE_NAME_EXTENSION = ".class";
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private static final String PATH_SEPARATOR_SYS_PROP = System.getProperty("path.separator");
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private static final String JAVA_CLASS_PATH_SYS_PROP = System.getProperty("java.class.path");
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private final Set<ResourceInfo> resources;
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private ClassPath(Set<ResourceInfo> resources) {
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this.resources = resources;
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}
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public static ClassPath from(ClassLoader classloader) throws IOException {
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requireNonNull(classloader);
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Set<LocationInfo> locations = locationsFrom(classloader);
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Set<File> scanned = new LinkedHashSet<>();
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for (LocationInfo location : locations) {
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scanned.add(location.file());
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}
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Set<ResourceInfo> resources = new LinkedHashSet<>();
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for (LocationInfo location : locations) {
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resources.addAll(location.scanResources(scanned));
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}
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return new ClassPath(resources);
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}
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public Set<ClassInfo> getTopLevelClasses() {
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return resources.stream()
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.filter(r -> r instanceof ClassInfo)
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.map(r -> (ClassInfo) r)
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.filter(ClassInfo::isTopLevel)
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.collect(toSet());
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}
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public Set<ClassInfo> getTopLevelClassesRecursive(String packageName) {
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requireNonNull(packageName);
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String packagePrefix = packageName + '.';
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Set<ClassInfo> classes = new LinkedHashSet<>();
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for (ClassInfo classInfo : getTopLevelClasses()) {
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if (classInfo.getName().startsWith(packagePrefix)) {
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classes.add(classInfo);
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}
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}
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return unmodifiableSet(classes);
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}
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public static class ResourceInfo {
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private final File file;
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private final String resourceName;
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final ClassLoader loader;
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static ResourceInfo of(File file, String resourceName, ClassLoader loader) {
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return resourceName.endsWith(CLASS_FILE_NAME_EXTENSION)
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? new ClassInfo(file, resourceName, loader)
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: new ResourceInfo(file, resourceName, loader);
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}
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ResourceInfo(File file, String resourceName, ClassLoader loader) {
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this.file = requireNonNull(file);
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this.resourceName = requireNonNull(resourceName);
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this.loader = requireNonNull(loader);
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}
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public File getFile() {
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return file;
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}
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@Override
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public int hashCode() {
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return resourceName.hashCode();
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}
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@Override
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public boolean equals(Object obj) {
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if (obj instanceof ResourceInfo that) {
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return resourceName.equals(that.resourceName)
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&& loader == that.loader;
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}
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return false;
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}
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@Override
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public String toString() {
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return resourceName;
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}
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}
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public static final class ClassInfo extends ResourceInfo {
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private final String className;
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ClassInfo(File file, String resourceName, ClassLoader loader) {
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super(file, resourceName, loader);
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this.className = getClassName(resourceName);
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}
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public String getName() {
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return className;
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}
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public boolean isTopLevel() {
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return className.indexOf('$') == -1;
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}
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@Override
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public String toString() {
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return className;
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}
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}
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static Set<LocationInfo> locationsFrom(ClassLoader classloader) {
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Set<LocationInfo> locations = new LinkedHashSet<>();
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for (Map.Entry<File, ClassLoader> entry : getClassPathEntries(classloader).entrySet()) {
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locations.add(new LocationInfo(entry.getKey(), entry.getValue()));
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}
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return unmodifiableSet(locations);
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}
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static final class LocationInfo {
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final File home;
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private final ClassLoader classloader;
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LocationInfo(File home, ClassLoader classloader) {
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this.home = requireNonNull(home);
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this.classloader = requireNonNull(classloader);
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}
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public File file() {
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return home;
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}
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public Set<ResourceInfo> scanResources(Set<File> scannedFiles) throws IOException {
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Set<ResourceInfo> resources = new LinkedHashSet<>();
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scannedFiles.add(home);
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scan(home, scannedFiles, resources);
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return unmodifiableSet(resources);
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}
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private void scan(File file, Set<File> scannedUris, Set<ResourceInfo> result)
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throws IOException {
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try {
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if (!file.exists()) {
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return;
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}
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} catch (SecurityException e) {
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logger.warn("Cannot access " + file + ": " + e);
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return;
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}
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if (file.isDirectory()) {
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scanDirectory(file, result);
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} else {
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scanJar(file, scannedUris, result);
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}
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}
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private void scanJar(File file, Set<File> scannedUris, Set<ResourceInfo> result) throws IOException {
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JarFile jarFile;
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try {
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jarFile = new JarFile(file);
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} catch (IOException e) {
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// Not a jar file
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return;
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}
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try {
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for (File path : getClassPathFromManifest(file, jarFile.getManifest())) {
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// We only scan each file once independent of the classloader that file might be
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// associated with.
199+
if (scannedUris.add(path.getCanonicalFile())) {
200+
scan(path, scannedUris, result);
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}
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}
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scanJarFile(jarFile, result);
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} finally {
205+
try {
206+
jarFile.close();
207+
} catch (IOException ignored) { // similar to try-with-resources, but don't fail scanning
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}
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}
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}
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private void scanJarFile(JarFile file, Set<ResourceInfo> result) {
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Enumeration<JarEntry> entries = file.entries();
214+
while (entries.hasMoreElements()) {
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JarEntry entry = entries.nextElement();
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if (entry.isDirectory() || entry.getName().equals(JarFile.MANIFEST_NAME)) {
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continue;
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}
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result.add(ResourceInfo.of(new File(file.getName()), entry.getName(), classloader));
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}
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}
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private void scanDirectory(File directory, Set<ResourceInfo> result)
224+
throws IOException {
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Set<File> currentPath = new HashSet<>();
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currentPath.add(directory.getCanonicalFile());
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scanDirectory(directory, "", currentPath, result);
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}
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private void scanDirectory(
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File directory,
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String packagePrefix,
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Set<File> currentPath,
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Set<ResourceInfo> builder
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) throws IOException {
236+
File[] files = directory.listFiles();
237+
if (files == null) {
238+
logger.warn("Cannot read directory " + directory);
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// IO error, just skip the directory
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return;
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}
242+
for (File f : files) {
243+
String name = f.getName();
244+
if (f.isDirectory()) {
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File deref = f.getCanonicalFile();
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if (currentPath.add(deref)) {
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scanDirectory(deref, packagePrefix + name + "/", currentPath, builder);
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currentPath.remove(deref);
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}
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} else {
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String resourceName = packagePrefix + name;
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if (!resourceName.equals(JarFile.MANIFEST_NAME)) {
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builder.add(ResourceInfo.of(f, resourceName, classloader));
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}
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}
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}
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}
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@Override
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public boolean equals(Object obj) {
261+
if (obj instanceof LocationInfo that) {
262+
return home.equals(that.home) && classloader.equals(that.classloader);
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}
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return false;
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}
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@Override
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public int hashCode() {
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return home.hashCode();
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}
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@Override
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public String toString() {
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return home.toString();
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}
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}
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static Set<File> getClassPathFromManifest(File jarFile, Manifest manifest) {
279+
if (manifest == null) {
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return Set.of();
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}
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Set<File> result = new LinkedHashSet<>();
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String classpathAttribute = manifest
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.getMainAttributes()
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.getValue(Attributes.Name.CLASS_PATH.toString());
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if (classpathAttribute != null) {
287+
for (String path : classpathAttribute.split(" ")) {
288+
if (path.isBlank()) {
289+
continue;
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}
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URL url;
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try {
293+
url = getClassPathEntry(jarFile, path);
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} catch (MalformedURLException e) {
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// Ignore bad entry
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logger.warn("Invalid Class-Path entry: " + path);
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continue;
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}
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if (url.getProtocol().equals("file")) {
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result.add(toFile(url));
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}
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}
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}
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return unmodifiableSet(result);
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}
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static Map<File, ClassLoader> getClassPathEntries(ClassLoader classloader) {
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LinkedHashMap<File, ClassLoader> entries = new LinkedHashMap<>();
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// Search parent first, since it's the order ClassLoader#loadClass() uses.
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ClassLoader parent = classloader.getParent();
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if (parent != null) {
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entries.putAll(getClassPathEntries(parent));
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}
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for (URL url : getClassLoaderUrls(classloader)) {
315+
if (url.getProtocol().equals("file")) {
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File file = toFile(url);
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if (!entries.containsKey(file)) {
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entries.put(file, classloader);
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}
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}
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}
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return unmodifiableMap(entries);
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}
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private static List<URL> getClassLoaderUrls(ClassLoader classloader) {
326+
if (classloader instanceof URLClassLoader) {
327+
return Arrays.asList(((URLClassLoader) classloader).getURLs());
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}
329+
if (classloader.equals(ClassLoader.getSystemClassLoader())) {
330+
return parseJavaClassPath();
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}
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return List.of();
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}
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private static List<URL> parseJavaClassPath() {
336+
List<URL> urls = new ArrayList<>();
337+
for (String entry : JAVA_CLASS_PATH_SYS_PROP.split(PATH_SEPARATOR_SYS_PROP)) {
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try {
339+
try {
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urls.add(new File(entry).toURI().toURL());
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} catch (SecurityException e) { // File.toURI checks to see if the file is a directory
342+
urls.add(new URL("file", null, new File(entry).getAbsolutePath()));
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}
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} catch (MalformedURLException e) {
345+
logger.warn("Malformed classpath entry: " + entry, e);
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}
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}
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return unmodifiableList(urls);
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}
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private static URL getClassPathEntry(File jarFile, String path) throws MalformedURLException {
352+
return new URL(jarFile.toURI().toURL(), path);
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}
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private static String getClassName(String filename) {
356+
int classNameEnd = filename.length() - CLASS_FILE_NAME_EXTENSION.length();
357+
return filename.substring(0, classNameEnd).replace('/', '.');
358+
}
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private static File toFile(URL url) {
361+
try {
362+
return new File(url.toURI()); // Accepts escaped characters like %20.
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} catch (URISyntaxException e) { // URL.toURI() doesn't escape chars.
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return new File(url.getPath()); // Accepts non-escaped chars like space.
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}
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}
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}

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