CriticalFile-scopeJava Plug & play

Do Not Call `wait()` When Holding Multiple Locks

Ensure that wait() is not called while holding multiple locks to prevent deadlocks.

Why this matters

Calling wait() while holding multiple locks can cause deadlocks if no other thread tries to acquire the awaited object. Always release locks before calling wait().

Bad vs. good

Side-by-side examples engineers can pattern-match during review.

Avoid

synchronized (this.mon1) {  // threadB can't enter this block to request this.mon2 lock & release threadA
	synchronized (this.mon2) {
		this.mon2.wait();  // Noncompliant; threadA is stuck here holding lock on this.mon1
	}
}

Prefer

// (no example provided)

Related rules

From the same buckets as this rule.

Critical
Avoid Blocking Calls to Async Methods
Blocking async methods with `.Result` or `.Wait()` can cause deadlocks and prevent efficient asynchronous execution. Use `await` instead for proper async behavior.
concurrency-safetyperformance-efficiency
High
Avoid Using Mutable Global Variables
Identify global variables that are mutable (e.g., lists, dictionaries). Global mutable state can cause unpredictable behavior. Recommend using local variables or encapsulating state in a class.
concurrency-safetymaintainability+1
High
Await async operations properly
Await Tasks instead of blocking (no .Result or .Wait()); prefer async/await end-to-end and configure awaits appropriately.
concurrency-safetyerror-handling

Why this matters

Bad vs. good

Related rules

Avoid Blocking Calls to Async Methods

Avoid Using Mutable Global Variables

Await async operations properly

Why this matters

Bad vs. good

Related rules

Avoid Blocking Calls to Async Methods

Avoid Using Mutable Global Variables

Await async operations properly