There is often a tension between safety and liveness. We use locking to ensure thread safety, but indiscriminate use of locking can cause lock-ordering deadlocks. Similarly, we use thread pools and semaphores to bound resource consumption, but failure to understand the activities being bounded can cause resource deadlocks. Java applications do not recover from deadlock, so it is worthwhile to ensure that your design precludes the conditions that could cause it. This chapter explores some of the causes of liveness failures and what can be done to prevent them.
Introduction
Part I: Fundamentals
Thread Safety
Sharing Objects
Composing Objects
Building Blocks
Part II: Structuring Concurrent Applications
Task Execution
Cancellation and Shutdown
Applying Thread Pools
GUI Applications
Part III: Liveness, Performance, and Testing
Avoiding Liveness Hazards
Performance and Scalability
Testing Concurrent Programs
Part IV: Advanced Topics
Explicit Locks
Building Custom Synchronizers
Atomic Variables and Nonblocking Synchronization
The Java Memory Model