GUACAMOLE-942: Merge correct race condition in retrieval of readable connection identifiers.
diff --git a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/tunnel/AbstractGuacamoleTunnelService.java b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/tunnel/AbstractGuacamoleTunnelService.java
index 383ef3a..6687eb3 100644
--- a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/tunnel/AbstractGuacamoleTunnelService.java
+++ b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/tunnel/AbstractGuacamoleTunnelService.java
@@ -623,21 +623,26 @@
public Collection<ActiveConnectionRecord> getActiveConnections(ModeledAuthenticatedUser user)
throws GuacamoleException {
- // Simply return empty list if there are no active tunnels
- Collection<ActiveConnectionRecord> records = activeTunnels.values();
- if (records.isEmpty())
- return Collections.<ActiveConnectionRecord>emptyList();
-
// Privileged users (such as system administrators) can view all
// connections; no need to filter
+ Collection<ActiveConnectionRecord> records = activeTunnels.values();
if (user.isPrivileged())
return records;
// Build set of all connection identifiers associated with active tunnels
- Set<String> identifiers = new HashSet<String>(records.size());
+ Set<String> identifiers = new HashSet<>(records.size());
for (ActiveConnectionRecord record : records)
identifiers.add(record.getConnection().getIdentifier());
+ // Simply return empty list if there are no active tunnels (note that
+ // this check cannot be performed prior to building the set of
+ // identifiers, as activeTunnels may be non-empty at the beginning of
+ // the call to getActiveConnections() yet become empty before the
+ // set of identifiers is built, resulting in an error within
+ // selectReadable()
+ if (identifiers.isEmpty())
+ return Collections.<ActiveConnectionRecord>emptyList();
+
// Produce collection of readable connection identifiers
Collection<ConnectionModel> connections =
connectionMapper.selectReadable(user.getUser().getModel(),
@@ -649,7 +654,7 @@
identifiers.add(connection.getIdentifier());
// Produce readable subset of records
- Collection<ActiveConnectionRecord> visibleRecords = new ArrayList<ActiveConnectionRecord>(records.size());
+ Collection<ActiveConnectionRecord> visibleRecords = new ArrayList<>(records.size());
for (ActiveConnectionRecord record : records) {
if (identifiers.contains(record.getConnection().getIdentifier()))
visibleRecords.add(record);
