Bug 567595 - fix quadratic runtime of resolveRuntimeClasspath
JavaRuntime.resolveRuntimeClasspath first resolves the classpath and
then removes the entry for the JRE. The latter step has quadratic
runtime over the length of the classpath. It iterates over all entries.
For each entry it calls JavaProject.findPackageFragmentRoot(), which
calls JavaProject.getAllPackageFragmentRoots() and then iterates
over all package fragment roots.
Fixed by computing the path to the JRE before the outer loop. This
reduces the runtime to O(n).
Signed-off-by: Andreas Huber <ahe@lucares.de>
Change-Id: I3e37c1cfce26d82dbcaf814bc27c5722fee9e22a
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.debug/+/180456
Tested-by: JDT Bot <jdt-bot@eclipse.org>
Reviewed-by: Andrey Loskutov <loskutov@gmx.de>
diff --git a/org.eclipse.jdt.launching/launching/org/eclipse/jdt/launching/JavaRuntime.java b/org.eclipse.jdt.launching/launching/org/eclipse/jdt/launching/JavaRuntime.java
index e01afd6..5c3f10f 100644
--- a/org.eclipse.jdt.launching/launching/org/eclipse/jdt/launching/JavaRuntime.java
+++ b/org.eclipse.jdt.launching/launching/org/eclipse/jdt/launching/JavaRuntime.java
@@ -1658,41 +1658,59 @@
* @since 2.0
*/
public static IRuntimeClasspathEntry[] resolveRuntimeClasspath(IRuntimeClasspathEntry[] entries, ILaunchConfiguration configuration) throws CoreException {
- if (isModularConfiguration(configuration)) {
- IRuntimeClasspathEntry[] entries1 = getClasspathProvider(configuration).resolveClasspath(entries, configuration);
- ArrayList<IRuntimeClasspathEntry> entries2 = new ArrayList<>(entries1.length);
+ if (!isModularConfiguration(configuration)) {
+ return getClasspathProvider(configuration).resolveClasspath(entries, configuration);
+ }
+ IRuntimeClasspathEntry[] entries1 = getClasspathProvider(configuration).resolveClasspath(entries, configuration);
+ List<IRuntimeClasspathEntry> entries2 = new ArrayList<>(entries1.length);
+ IJavaProject project;
+ try {
+ project = JavaRuntime.getJavaProject(configuration);
+ } catch (CoreException e) {
+ project = null;
+ }
+ if (project == null) {
+ entries2.addAll(Arrays.asList(entries1));
+ } else {
+ // Add all entries except the one from JRE itself
+ IPackageFragmentRoot jreContainer = findJreContainer(project);
+ IPath canonicalJrePath = jreContainer != null ? JavaProject.canonicalizedPath(jreContainer.getPath()) : null;
+
for (IRuntimeClasspathEntry entry : entries1) {
switch (entry.getClasspathEntry().getEntryKind()) {
case IClasspathEntry.CPE_LIBRARY:
- try {
- IJavaProject project = JavaRuntime.getJavaProject(configuration);
- if (project == null) {
- entries2.add(entry);
- }
- else {
- IPackageFragmentRoot root = project.findPackageFragmentRoot(entry.getPath());
- if (root == null && !entry.getPath().lastSegment().contains("jrt-fs.jar")) { //$NON-NLS-1$
- entries2.add(entry);
- } else if (root != null && !root.getRawClasspathEntry().getPath().segment(0).contains("JRE_CONTAINER")) { //$NON-NLS-1$
- entries2.add(entry);
- }
- }
- }
- catch (CoreException ex) {
- // Not a java project
- if (!entry.getPath().lastSegment().contains("jrt-fs.jar")) { //$NON-NLS-1$
- entries2.add(entry);
- }
+ if (!entry.getPath().lastSegment().contains("jrt-fs.jar") //$NON-NLS-1$
+ && (canonicalJrePath == null || !canonicalJrePath.equals(JavaProject.canonicalizedPath(entry.getPath())))) {
+ entries2.add(entry);
}
break;
default:
entries2.add(entry);
-
}
}
- return entries2.toArray(new IRuntimeClasspathEntry[entries2.size()]);
}
- return getClasspathProvider(configuration).resolveClasspath(entries, configuration);
+ return entries2.toArray(new IRuntimeClasspathEntry[entries2.size()]);
+ }
+
+ /**
+ * Find the {@link IPackageFragmentRoot} of the JRE container for the given project, if it exists.
+ *
+ * @param project
+ * Java project
+ * @return the {@link IPackageFragmentRoot} for the JRE container or null if no JRE container is on the classpath
+ * @throws JavaModelException
+ */
+ private static IPackageFragmentRoot findJreContainer(IJavaProject project) throws JavaModelException {
+ IPackageFragmentRoot jreContainer = null;
+
+ IPackageFragmentRoot[] allPackageFragmentRoots = project.getAllPackageFragmentRoots();
+ for (IPackageFragmentRoot packageFragmentRoot : allPackageFragmentRoots) {
+ if (packageFragmentRoot.getRawClasspathEntry().getPath().segment(0).contains("JRE_CONTAINER")) { //$NON-NLS-1$
+ jreContainer = packageFragmentRoot;
+ break;
+ }
+ }
+ return jreContainer;
}
/**
