diff options
| -rw-r--r-- | src/launch/lombok/launch/ShadowClassLoader.java | 99 |
1 files changed, 82 insertions, 17 deletions
diff --git a/src/launch/lombok/launch/ShadowClassLoader.java b/src/launch/lombok/launch/ShadowClassLoader.java index 985a0a2a..99f632a0 100644 --- a/src/launch/lombok/launch/ShadowClassLoader.java +++ b/src/launch/lombok/launch/ShadowClassLoader.java @@ -26,12 +26,15 @@ import java.io.IOException; import java.io.InputStream; import java.net.MalformedURLException; import java.net.URI; -import java.net.URISyntaxException; import java.net.URL; import java.util.ArrayList; +import java.util.Collections; import java.util.Enumeration; +import java.util.HashMap; import java.util.List; +import java.util.Map; import java.util.Vector; +import java.util.WeakHashMap; import java.util.jar.JarEntry; import java.util.jar.JarFile; @@ -108,6 +111,64 @@ class ShadowClassLoader extends ClassLoader { } } + private static final String EMPTY_MARKER = new String("--EMPTY JAR--"); + private Map<String, Object> jarContentsCacheTrackers = new HashMap<String, Object>(); + private static WeakHashMap<Object, String> trackerCache = new WeakHashMap<Object, String>(); + private static WeakHashMap<Object, List<String>> jarContentsCache = new WeakHashMap<Object, List<String>>(); + + /** + * This cache ensures that any given jar file is only opened once in order to determine the full contents of it. + * We use 'trackers' to make sure that the bulk of the memory taken up by this cache (the list of strings representing the content of a jar file) + * gets garbage collected if all ShadowClassLoaders that ever tried to request a listing of this jar file, are garbage collected. + */ + private List<String> getOrMakeJarListing(String absolutePathToJar) { + List<String> list = retrieveFromCache(absolutePathToJar); + synchronized (list) { + if (list.isEmpty()) { + try { + JarFile jf = new JarFile(absolutePathToJar); + try { + Enumeration<JarEntry> entries = jf.entries(); + while (entries.hasMoreElements()) { + JarEntry jarEntry = entries.nextElement(); + if (!jarEntry.isDirectory()) list.add(jarEntry.getName()); + } + } finally { + jf.close(); + } + } catch (Exception ignore) {} + if (list.isEmpty()) list.add(EMPTY_MARKER); + } + } + + if (list.size() == 1 && list.get(0) == EMPTY_MARKER) return Collections.emptyList(); + return list; + } + + private List<String> retrieveFromCache(String absolutePathToJar) { + synchronized (trackerCache) { + Object tracker = jarContentsCacheTrackers.get(absolutePathToJar); + if (tracker != null) return jarContentsCache.get(tracker); + + for (Map.Entry<Object, String> entry : trackerCache.entrySet()) { + if (entry.getValue().equals(absolutePathToJar)) { + tracker = entry.getKey(); + break; + } + } + List<String> result = null; + if (tracker != null) result = jarContentsCache.get(tracker); + if (result != null) return result; + + tracker = new Object(); + List<String> list = new ArrayList<String>(); + jarContentsCache.put(tracker, list); + trackerCache.put(tracker, absolutePathToJar); + jarContentsCacheTrackers.put(absolutePathToJar, tracker); + return list; + } + } + private URL getResourceFromLocation(String name, String altName, File location) { if (location.isDirectory()) { try { @@ -126,24 +187,28 @@ class ShadowClassLoader extends ClassLoader { if (!location.isFile() || !location.canRead()) return null; - JarFile jf = null; - JarEntry entry = null; + String absolutePath; { + try { + absolutePath = location.getCanonicalPath(); + } catch (Exception e) { + absolutePath = location.getAbsolutePath(); + } + } + List<String> jarContents = getOrMakeJarListing(absolutePath); try { - jf = new JarFile(location); - if (altName != null) entry = jf.getJarEntry(altName); - if (entry == null) entry = jf.getJarEntry(name); - if (entry == null) return null; - return new URI("jar:file:" + location.getAbsolutePath() + "!/" + entry.getName()).toURL(); - } catch (IOException e) { - return null; - } catch (URISyntaxException e) { - return null; - } finally { - if (jf != null) try { - jf.close(); - } catch (Exception ignore) {} - } + if (jarContents.contains(altName)) { + return new URI("jar:file:" + absolutePath + "!/" + altName).toURL(); + } + } catch (Exception e) {} + + try { + if (jarContents.contains(name)) { + return new URI("jar:file:" + absolutePath + "!/" + name).toURL(); + } + } catch(Exception e) {} + + return null; } private boolean inOwnBase(URL item, String name) { |