Use stream-based directory listing for counting sessions
There is no need to accumulate in memory all the list
of files in the websessions directory: use the native
Java Streams that supports counting.
Change-Id: I2e59bb4e38b79febd466cccaacaf1a0d1852984c
diff --git a/src/main/java/com/googlesource/gerrit/plugins/websession/flatfile/FlatFileWebSessionCache.java b/src/main/java/com/googlesource/gerrit/plugins/websession/flatfile/FlatFileWebSessionCache.java
index 18e8a94..a89e202 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/websession/flatfile/FlatFileWebSessionCache.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/websession/flatfile/FlatFileWebSessionCache.java
@@ -45,6 +45,8 @@
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ExecutionException;
import java.util.function.Consumer;
+import java.util.stream.Stream;
+import java.util.stream.StreamSupport;
@Singleton
public class FlatFileWebSessionCache implements Cache<String, WebSessionManager.Val> {
@@ -190,7 +192,7 @@
@Override
public long size() {
- return listFiles().size();
+ return sessionStream().count();
}
@Override
@@ -228,7 +230,7 @@
private List<Path> listFiles() {
List<Path> files = new ArrayList<>();
- try (DirectoryStream<Path> dirStream = Files.newDirectoryStream(websessionsDir)) {
+ try (DirectoryStream<Path> dirStream = sessionDirectoryStream()) {
for (Path path : dirStream) {
files.add(path);
}
@@ -239,10 +241,24 @@
}
private void foreachSession(Consumer<Path> sessionPath) {
- try (DirectoryStream<Path> dirStream = Files.newDirectoryStream(websessionsDir)) {
+ try (DirectoryStream<Path> dirStream = sessionDirectoryStream()) {
dirStream.forEach(sessionPath);
} catch (IOException e) {
log.atSevere().withCause(e).log("Cannot list files in cache %s", websessionsDir);
}
}
+
+ private Stream<Path> sessionStream() {
+ try {
+ return StreamSupport.stream(
+ sessionDirectoryStream().spliterator(), false /* single-threaded */);
+ } catch (IOException e) {
+ log.atSevere().withCause(e).log("Cannot traverse files in cache %s", websessionsDir);
+ return Stream.empty();
+ }
+ }
+
+ private DirectoryStream<Path> sessionDirectoryStream() throws IOException {
+ return Files.newDirectoryStream(websessionsDir);
+ }
}
