Java_并发编程培训选编.ppt

java.text.SimpleDateFormat并不是线程安全的，然而直到JDK1.4以前的Javadoc，都忽略了提及这一点， Jdk1.6已经优化了synchronized， Jdk1.6已经优化了synchronized， Concurrent Building Blocks 1. Data Structures: A set of lockfree collection classes. Since these datastructures were developed using lockfree algorithms, they enjoy some of the basic lockfree properties like, immunity from different types of deadlocks, immunity for priority inversion, etc. 2. Patterns and Scheduling Algorithms: Most application parallelization efforts follow one or more of a number of well known parallel computation patterns. We provide a set of patterns that developers can directly leverage to build parallel applications. The patterns we propose to provide will include (but not limited to): Master-Worker, Map-reduce, Divide and conquer, Pipeline, etc. We also plan to provide a set of schedulers. The schedulers can be used in conjunction with the patterns classes. 3. Parallel implementations of general-purpose functions: Example of functions to include, but not limited to: 1. String, Sequence and Array functions: Sort, Search, Merge, Rank, Compare, Reverse, Shuffle, Rotate, Median, etc. 2. Tree and Graph functions: Connected Components, Spanning Trees, Shortest Path, Graph Coloring, etc. 4. Atomics, STM, etc. 1. Deliver a C++ implementation of atomics. This implementation will be based on the draft of the C++ standards definition of the interface for atomics. 2. Deliver an open, flexible implementation of Software Transactional Memory. STM(Software transactional memory): In computer science, software transactional memory (STM) is a concurrency control mechanism analogous to database transactions for controlling access to shared memory in concurrent computing. It is an alternative to lock-based synchronization. A transaction in this context is a piece of code that executes a series of reads and writes to shared memory. These reads and writes logically occur at a single instant in time; intermediate states are