--- a/jdk/src/java.base/share/classes/jdk/internal/module/SystemModuleFinder.java Thu Feb 09 17:21:47 2017 +0000
+++ b/jdk/src/java.base/share/classes/jdk/internal/module/SystemModuleFinder.java Fri Feb 10 09:04:39 2017 +0000
@@ -80,8 +80,6 @@
= PerfCounter.newPerfCounter("jdk.module.finder.jimage.packages");
private static final PerfCounter exportsCount
= PerfCounter.newPerfCounter("jdk.module.finder.jimage.exports");
- // ImageReader used to access all modules in the image
- private static final ImageReader imageReader;
// singleton finder to find modules in the run-time images
private static final SystemModuleFinder INSTANCE;
@@ -96,13 +94,28 @@
*/
static {
long t0 = System.nanoTime();
- imageReader = ImageReaderFactory.getImageReader();
INSTANCE = new SystemModuleFinder();
initTime.addElapsedTimeFrom(t0);
}
+ /**
+ * Holder class for the ImageReader
+ */
+ private static class SystemImage {
+ static final ImageReader READER;
+ static {
+ long t0 = System.nanoTime();
+ READER = ImageReaderFactory.getImageReader();
+ initTime.addElapsedTimeFrom(t0);
+ }
+
+ static ImageReader reader() {
+ return READER;
+ }
+ }
+
private static boolean isFastPathSupported() {
return SystemModules.MODULE_NAMES.length > 0;
}
@@ -114,7 +127,7 @@
// this happens when java.base is patched with java.base
// from an exploded image
- return imageReader.getModuleNames();
+ return SystemImage.reader().getModuleNames();
}
// the set of modules in the run-time image
@@ -151,6 +164,7 @@
descriptors = new ModuleDescriptor[n];
recordedHashes = new ModuleHashes[n];
moduleResolutions = new ModuleResolution[n];
+ ImageReader imageReader = SystemImage.reader();
for (int i = 0; i < names.length; i++) {
String mn = names[i];
ImageLocation loc = imageReader.findLocation(mn, "module-info.class");
@@ -291,6 +305,7 @@
Objects.requireNonNull(name);
if (closed)
throw new IOException("ModuleReader is closed");
+ ImageReader imageReader = SystemImage.reader();
if (imageReader != null) {
return imageReader.findLocation(module, name);
} else {
@@ -330,7 +345,7 @@
public Optional<ByteBuffer> read(String name) throws IOException {
ImageLocation location = findImageLocation(name);
if (location != null) {
- return Optional.of(imageReader.getResourceBuffer(location));
+ return Optional.of(SystemImage.reader().getResourceBuffer(location));
} else {
return Optional.empty();
}
@@ -372,7 +387,7 @@
stack = new ArrayDeque<>();
// push the root node to the stack to get started
- ImageReader.Node dir = imageReader.findNode(moduleRoot);
+ ImageReader.Node dir = SystemImage.reader().findNode(moduleRoot);
if (dir == null || !dir.isDirectory())
throw new IOException(moduleRoot + " not a directory");
stack.push(dir);
@@ -390,7 +405,7 @@
String name = node.getName();
if (node.isDirectory()) {
// build node
- ImageReader.Node dir = imageReader.findNode(name);
+ ImageReader.Node dir = SystemImage.reader().findNode(name);
assert dir.isDirectory();
stack.push(dir);
} else {