/**
* finds all the entries on the classpath; this includes jars and class folders on all class
* loaders, all the way down and including the JVM bootstrap class loader.
*
* @return a list of classpath entries, or an empty list if none where found.
*/
public List<ClasspathEntry> findAllClasspathEntries() {
// try to extract all classpath entries from the class loaders
List<ClazzLoader> classLoaders = findAllClassLoaders(getClass().getClassLoader());
List<ClasspathEntry> allClasspathEntries = ClazzLoaders.findAllClasspathEntries(classLoaders);
// scan the class path variable for missing entries, just in case
String classpath = System.getProperty("java.class.path");
String separator = System.getProperty("path.separator");
if (classpath != null && separator != null) {
String[] paths = classpath.split(separator);
for (String pathEntry : paths) {
boolean found = false;
for (ClasspathEntry classpathEntry : allClasspathEntries) {
if (classpathEntry.getUrl().contains(pathEntry)) {
found = true;
break;
}
}
if (!found) {
if (!pathEntry.endsWith("/")) {
pathEntry = pathEntry + "/";
}
logger.warn(
"This entry on the classpath system property java.class.path was not found on any classloader:"
+ pathEntry);
}
}
} else {
logger.warn("could not parse classpath.");
}
return allClasspathEntries;
}
/**
* This class contains a series of commands for querying the classpath.
*
* <p>The classpath is scanned from the classloader where the scanner was created, going all the way
* down to the bootstrap classloader.
*
* <p>For each classloader, the location of it's jars and class folders is extracted. Each jar/class
* folder is unzipped and scanned for class files and any other types of resource files.
*
* <p>If the classpath scanner was created on the top-most class loader of the application, it
* should be able to access all the classes / resource files of your application.
*
* <p>It's possible in some cases that some classes are not found via classloader inspection, here
* are 2 known cases:
*
* <p>1. jHades was NOT created on the top-most class loader, this should be very uncommon
*
* <p>2. One of your classloaders is not yet supported - there should be a warning message on your
* log.
*
* <p>The classpath folders and jars are scanned using JDK 7 functionality provided by the Java NIO
* framework.
*
* <p>jHades only depends on JDK 7 classes, in order to prevent introducing library dependencies
* (that could themselves cause classpath problems).
*
* <p>Note: For the moment jHades only supports URL class loaders,
*
* @see ClazzLoaderFactory
*/
public class ClasspathScanner {
public static final String BOOTSTRAP_CLASS_LOADER = "Bootstrap class loader";
private StdOutLogger logger = StdOutLogger.getLogger();
/**
* finds all the entries on the classpath; this includes jars and class folders on all class
* loaders, all the way down and including the JVM bootstrap class loader.
*
* @return a list of classpath entries, or an empty list if none where found.
*/
public List<ClasspathEntry> findAllClasspathEntries() {
// try to extract all classpath entries from the class loaders
List<ClazzLoader> classLoaders = findAllClassLoaders(getClass().getClassLoader());
List<ClasspathEntry> allClasspathEntries = ClazzLoaders.findAllClasspathEntries(classLoaders);
// scan the class path variable for missing entries, just in case
String classpath = System.getProperty("java.class.path");
String separator = System.getProperty("path.separator");
if (classpath != null && separator != null) {
String[] paths = classpath.split(separator);
for (String pathEntry : paths) {
boolean found = false;
for (ClasspathEntry classpathEntry : allClasspathEntries) {
if (classpathEntry.getUrl().contains(pathEntry)) {
found = true;
break;
}
}
if (!found) {
if (!pathEntry.endsWith("/")) {
pathEntry = pathEntry + "/";
}
logger.warn(
"This entry on the classpath system property java.class.path was not found on any classloader:"
+ pathEntry);
}
}
} else {
logger.warn("could not parse classpath.");
}
return allClasspathEntries;
}
/**
* Scans the classpath for all resource files.
*
* @return - the full list of resources on the classpath, including all its known versions.
*/
public List<ClasspathResource> findAllClasspathResources() {
List<ClasspathEntry> classpathEntries = findAllClasspathEntries();
return ClasspathEntries.findClasspathResourcesInEntries(classpathEntries, logger, null);
}
/**
* Finds all class loaders on the classpath.
*
* <p>All classloaders names will be returned, with an indication if they are supported by jHades
* or not.
*
* @return
*/
public List<ClazzLoader> findAllClassLoaders() {
return findAllClassLoaders(getClass().getClassLoader());
}
/**
* Find all versions of a given classpath resource.
*
* @param resourceUrl - the resource url being searched
* @return - a list of urls to all versions of the resource, or an empty list if not found.
*/
public List<URL> findAllResourceVersions(String resourceUrl) {
ClassLoader cl = getClass().getClassLoader();
List<URL> results = new ArrayList<>();
try {
Enumeration<URL> urls = cl.getResources(resourceUrl);
while (urls.hasMoreElements()) {
results.add(urls.nextElement());
}
} catch (IOException exception) {
System.out.println("Could not find the versions of classpath resource: " + resourceUrl);
exception.printStackTrace();
}
return results;
}
/**
* Finds the version of a classpath resource that is currently being loaded by the JVM.
*
* @param resourceUrl - the url of the classpath resource
* @return - the URL of the resource version being used, or null if not found.
*/
public URL findCurrentResourceVersion(String resourceUrl) {
ClassLoader cl = getClass().getClassLoader();
return cl.getResource(resourceUrl);
}
/**
* Search for a given class on the classpath, returns the list of all class versions.
*
* @param clazz - the class being searched.
* @return - the classpath resource containing all the class versions, or null if not found
*/
public ClasspathResource findClass(Class clazz) {
String classResourceName = clazz.getName().replace(".", "/") + ".class";
List<ClasspathResource> allResources = findAllClasspathResources();
ClasspathResource foundResource = null;
for (ClasspathResource resource : allResources) {
if (resource != null
&& resource.getName() != null
&& resource.getName().endsWith(classResourceName)) {
foundResource = resource;
break;
}
}
return foundResource;
}
/**
* finds a resource on the classpath using a regular expression.
*
* @param search - search regular expression
* @return - the list of classpath resources that match the regular expression
*/
public List<ClasspathResource> findByRegex(String search) {
List<ClasspathResource> allResources = findAllClasspathResources();
List<ClasspathResource> matches = new ArrayList<>();
Pattern pattern = Pattern.compile(search);
for (ClasspathResource resource : allResources) {
if (resource != null
&& resource.getName() != null
&& pattern.matcher(resource.getName()).find()) {
matches.add(resource);
}
}
return matches;
}
/**
* Finds a list of all classpath resources that contain duplicates.
*
* <p>A duplicate classpath resource can be for example a configuration file such as log4.xml,
* that exists by accident multiple times on the classpath.
*
* @param excludeSameSizeDups - excludes from the reports files for which all classpath versions
* have the same size
* @return classpath resources that have multiple versions on the classpath
*/
public List<ClasspathResource> findAllResourcesWithDuplicates(boolean excludeSameSizeDups) {
List<ClasspathResource> resourceFiles = findAllClasspathResources();
return ClasspathResources.findResourcesWithDuplicates(resourceFiles, excludeSameSizeDups);
}
/**
* Searches for classpath entries on the classpath, starting on the given input classloader, and
* scanning recursively it's parents, all the way until the JVM bootstrap classloader.
*
* @param classLoader the class loader to be scanned
* @return the list of classpath entries found on the given class loader.
*/
private List<ClazzLoader> findAllClassLoaders(ClassLoader classLoader) {
List<ClazzLoader> classLoaders = new ArrayList<>();
if (classLoader != null) {
ClazzLoader cl = ClazzLoaderFactory.createClazzLoader(classLoader);
if (cl != null) {
classLoaders.add(cl);
}
classLoaders.addAll(findAllClassLoaders(classLoader.getParent()));
} // if the class loader is null, means we got all the way to the bootstrap class loader - add
// it as well
else {
classLoaders.add(ClazzLoaderFactory.createBootstrapClassLoader());
}
return classLoaders;
}
/**
* Finds all class files that have more than one version on the classpath
*
* @param classpathResources - the list of classpath resources
* @param excludeSameSizeDups - true if only duplicates of different class sizes are considered
* @return - the list of class files that have multiple versions
*/
public List<ClasspathResource> findClassFileDuplicates(
List<ClasspathResource> classpathResources, boolean excludeSameSizeDups) {
List<ClasspathResource> classFilesWithDuplicates =
ClasspathResources.findResourcesWithDuplicates(classpathResources, excludeSameSizeDups);
return ClasspathResources.filterClassFilesOnly(classFilesWithDuplicates);
}
/**
* @return - a list of jar pairs that have overlapping class files - scans the whole classpath
* <p>By default all duplicates are shown
*/
public List<JarPair> findOverlappingJars() {
return findOverlappingJars(findAllClasspathResources(), false);
}
/** @return - a list of jar pairs that have overlapping class files - scans the whole classpath */
public List<JarPair> findOverlappingJars(boolean excludeSameSizeDups) {
return findOverlappingJars(findAllClasspathResources(), excludeSameSizeDups);
}
/**
* @return - a list of jar pairs that have overlapping class files - only a limited list of
* classpath resources is considered.
*/
public List<JarPair> findOverlappingJars(
List<ClasspathResource> classpathResources, boolean excludeSameSizeDups) {
List<ClasspathResource> classFilesWithDuplicates =
findClassFileDuplicates(classpathResources, excludeSameSizeDups);
// jar overlap report
Map<JarPair, JarPair> overlapPairs = new HashMap<>();
for (ClasspathResource classFile : classFilesWithDuplicates) {
List<ClasspathResourceVersion> versions = classFile.getResourceFileVersions();
findOverlappingJarsPairs(versions, overlapPairs, 0);
}
List<JarPair> overlapReportLines = new ArrayList<>(overlapPairs.keySet());
Comparator<JarPair> comparator =
new Comparator<JarPair>() {
@Override
public int compare(JarPair line1, JarPair line2) {
return -1 * line1.getDupClassesTotal().compareTo(line2.getDupClassesTotal());
}
};
Collections.sort(overlapReportLines, comparator);
return overlapReportLines;
}
private void findOverlappingJarsPairs(
List<ClasspathResourceVersion> versions,
Map<JarPair, JarPair> overlapPairs,
int anchorIndex) {
ClasspathResourceVersion anchor = versions.get(anchorIndex);
for (int i = anchorIndex + 1; i < versions.size(); i++) {
JarPair overlapPair =
new JarPair(anchor.getClasspathEntry(), versions.get(i).getClasspathEntry());
if (!overlapPairs.containsKey(overlapPair)) {
overlapPairs.put(overlapPair, overlapPair);
}
overlapPairs.get(overlapPair).incrementDupClassesTotal();
}
if (anchorIndex + 1 < versions.size()) {
findOverlappingJarsPairs(versions, overlapPairs, anchorIndex + 1);
}
}
}
