It is critical to correctly activate threads. Thread activation can be misleading because sometimes the code appears to be performing the function correctly, whereas it may be operating in the presence of subtle concurrency issues.
Noncompliant Code Example
The run()
method of interface Runnable
must be invoked in its own thread, however, this noncompliant code example explicitly invokes it in the context of the current thread.
class Foo implements Runnable { public void run() { // ... } public static void main(String[] args) { Foo f = new foo(); new Thread(f).run(); } }
Compliant Solution
This compliant solution correctly uses the start()
method to start a new thread which then executes the run()
method.
class Foo implements Runnable { public void run() { // ... } public static void main(String[] args) { Foo f = new foo(); new Thread(f).start(); } }
Risk Assessment
Failing to activate threads correctly can cause unexpected behavior.
Rule |
Severity |
Likelihood |
Remediation Cost |
Priority |
Level |
---|---|---|---|---|---|
CON04- J |
low |
probable |
medium |
P4 |
L3 |
Automated Detection
TODO
Related Vulnerabilities
Search for vulnerabilities resulting from the violation of this rule on the CERT website.
References
[[API 06]] Interface Runnable
and class Thread
CON05-J. Do not defer a thread that is holding a lock 11. Concurrency (CON) CON00-J. Synchronize access to shared mutable variables