1666 var pacer = pacer();
1667 if ((pacer != null) && !pacer.isScheduled() && evictionLock.tryLock()) {
1668 try {
1669 if ((drainStatusOpaque() == REQUIRED) && !pacer.isScheduled()) {1670 pacer.schedule(executor, drainBuffersTask, expirationTicker().read(), Pacer.TOLERANCE);
1671 }
1672 } finally {1666 var pacer = pacer();
1667 if ((pacer != null) && !pacer.isScheduled() && evictionLock.tryLock()) {
1668 try {
1669 if ((drainStatusOpaque() == REQUIRED) && !pacer.isScheduled()) {1670 pacer.schedule(executor, drainBuffersTask, expirationTicker().read(), Pacer.TOLERANCE);
1671 }
1672 } finally {1667 if ((pacer != null) && !pacer.isScheduled() && evictionLock.tryLock()) {
1668 try {
1669 if ((drainStatusOpaque() == REQUIRED) && !pacer.isScheduled()) {
1670 pacer.schedule(executor, drainBuffersTask, expirationTicker().read(), Pacer.TOLERANCE);1671 }
1672 } finally {
1673 evictionLock.unlock();This code contains a possible null dereference that may occur based on whether an exception is thrown or not. Carefully check your code to ensure that the concerned value can never be null at this point.
Bad Practice
In the snippet below, whether the value of s stays null depends on whether mayThrow() throws an exception. If an
exception were thrown, the code would skip the assignment to s, which means it would remain as null until it is
accessed for a method call. This will lead to a NullPointerException being thrown.
String s = null;
try {
mayThrow();
s = "SomeValue";
} catch (SomeException e) {
// no assignment of s
}
int len = s.length; // This will be null if the method call throws!
Recommended
This could be fixed either by performing a check at the usage site, if the logic requires that s should possibly be
null:
int len = (s == null) ? 0 : s.length();
It could also be fixed by changing the preceding logic to correctly set the value of s at all points. For example, the
catch block could set s to a safe default value:
try {
// ...
} catch (SomeException e) {
s = "";
}
int len = s.length; // no exception!
References
- CWE-476 - Null Pointer Dereference