Explicit Locks
Before Java 5.0, the only mechanisms for coordinating access to shared data were synchronized and volatile. Java 5.0 adds another option: ReentrantLock. Contrary to what some have written, ReentrantLock is not a replacement for intrinsic locking, but rather an alternative with advanced features for when intrinsic locking proves too limited.
Lock and ReentrantLock |
Introduction
- Introduction
- A (Very) Brief History of Concurrency
- Benefits of Threads
- Risks of Threads
- Threads are Everywhere
Part I: Fundamentals
Thread Safety
- Thread Safety
- What is Thread Safety?
- Atomicity
- Locking
- Guarding State with Locks
- Liveness and Performance
Sharing Objects
Composing Objects
- Composing Objects
- Designing a Thread-safe Class
- Instance Confinement
- Delegating Thread Safety
- Adding Functionality to Existing Thread-safe Classes
- Documenting Synchronization Policies
Building Blocks
- Building Blocks
- Synchronized Collections
- Concurrent Collections
- Blocking Queues and the Producer-consumer Pattern
- Blocking and Interruptible Methods
- Synchronizers
- Building an Efficient, Scalable Result Cache
- Summary of Part I
Part II: Structuring Concurrent Applications
Task Execution
- Task Execution
- Executing Tasks in Threads
- The Executor Framework
- Finding Exploitable Parallelism
- Summary
Cancellation and Shutdown
- Cancellation and Shutdown
- Task Cancellation
- Stopping a Thread-based Service
- Handling Abnormal Thread Termination
- JVM Shutdown
- Summary
Applying Thread Pools
- Applying Thread Pools
- Implicit Couplings Between Tasks and Execution Policies
- Sizing Thread Pools
- Configuring ThreadPoolExecutor
- Extending ThreadPoolExecutor
- Parallelizing Recursive Algorithms
- Summary
GUI Applications
- GUI Applications
- Why are GUIs Single-threaded?
- Short-running GUI Tasks
- Long-running GUI Tasks
- Shared Data Models
- Other Forms of Single-threaded Subsystems
- Summary
Part III: Liveness, Performance, and Testing
Avoiding Liveness Hazards
Performance and Scalability
- Performance and Scalability
- Thinking about Performance
- Amdahls Law
- Costs Introduced by Threads
- Reducing Lock Contention
- Example: Comparing Map Performance
- Reducing Context Switch Overhead
- Summary
Testing Concurrent Programs
- Testing Concurrent Programs
- Testing for Correctness
- Testing for Performance
- Avoiding Performance Testing Pitfalls
- Complementary Testing Approaches
- Summary
Part IV: Advanced Topics
Explicit Locks
- Explicit Locks
- Lock and ReentrantLock
- Performance Considerations
- Fairness
- Choosing Between Synchronized and ReentrantLock
- Read-write Locks
- Summary
Building Custom Synchronizers
- Building Custom Synchronizers
- Managing State Dependence
- Using Condition Queues
- Explicit Condition Objects
- Anatomy of a Synchronizer
- AbstractQueuedSynchronizer
- AQS in Java.util.concurrent Synchronizer Classes
- Summary
Atomic Variables and Nonblocking Synchronization
- Atomic Variables and Nonblocking Synchronization
- Disadvantages of Locking
- Hardware Support for Concurrency
- Atomic Variable Classes
- Nonblocking Algorithms
- Summary
The Java Memory Model
EAN: 2147483647
Pages: 141
