【正文】 the number of garbage collection, and let JIT piler can optimize more After the code. ? Enhanced multicore support: the need to use tools, libraries, and builtin facilities to help new and existing Java applications more efficient use of the advantages of multicore hardware, Java39。s threading model can easily create parallel threads that execute tasks, but how do you to a single task into multiple slices parallel to enforce it? There are thirdparty software packages can help us, such as Pervasive39。s DataRush products, such as, Doug Lea modified Java Fork / Join Framework, adds this functionality to Java, directly to the frame added to the package, it the task will be recursively deposed into subtasks for parallel execution threads and coordination framework handles the task, when all subtasks consisting end result. Other improvements include continuous performance improvements, as well as many language enhancements, including increased closures for Strings in switch statements of support, and multiblock exception catching, closure is a controversial feature, it is through the use of anonymous The Java inner classes.Sun HotSpot and Oracle JRockit merger In my opinion, so far, the most surprising news is that HotSpot and JRockit merger. Over the years, the former BEA JVM and Sun39。s JVM has been plagued by performance and management capabilities, but now finally the King once again return to the performance benchmarks, the overall latency and garbage collection techniques to achieve the best results. Although many people think that Sun39。s HotSpot JIT piler technology is the best, but the JRockit garbage collection with its excellent technical and other performance enhancements make it a destination of choice for applications in some, such as the use of the financial sector was on the lot. In fact, JRockit Real features than Sun39。s Java RTS product advantage, because RTS often require modifying the application code. But Sun39。s HotSpot is considered the most reliable JVM, reliable and should be more important than speed, while, HotSpot support more binations of operating systems and hardware platforms. Given that both JVM has its own advantages, bined with the advantages of both will bring better results, so far, Oracle said that the JVM integration objectives are as follows: ? Enhanced management and monitoring: HotSpot brings its VisualVM and VisualGC tool that allows you to visualize the configuration, examine and analyze running Java applications, including their memory usage and performance. Oracle JRockit Mission Control provides a set of tools to achieve application execution, GC activity and the delay caused by a thread synchronization, IO or memory related issues Visualization report. In addition, JRockit Mission Control feature provides monitoring and reporting untrue. ? executed locally on the hypervisor: directly on the hardware running the Java Virtual Machine, beyond the traditional operating system limitation, which is Oracle39。s acquisition of BEA and Sun before the mon goal of the two panies. This design may eliminate the Java application and the hardware itself between a large number of software layers. In fact, Azul pany many years ago began the attempt to build specialized hardware and Java virtual machine to work together, thus eliminating the traditional operating system. By adding a hypervisor, Oracle eliminates dedicated hardware limitations, let the JVM can run in the data center have been deployed on all hardware platforms, such as Intel, AMD, and Sparcbased systems. ? Advanced garbage collection: a bination of Oracle / BEA and Sun in terms of technical precipitation garbage collection, and now and then how to say there should be a qualitative leap, Sun on the realtime behavior and throughput (Java SE 6 parallel collector) also alone achieved a GC (Java RTS Realtime garbage collection). Jrcokit support less recovery, but it allows you to specify the mode of operation. In addition, support for dynamic mode at runtime collector can choose the best garbage collection policy. The two sides have done a lot of interesting effort and work (Sun39。s work is G1 collector), and now the two sides should work together to create a better garbage collector. ? NUMA support for multicore systems: NonUniform Memory Access (NUMA) allow memory access time depends on the memory location relative to the physical location of the processor to execute code in the field of multicore processor technology is a hot topic. For example, in multicore processors, each core has its own local data cache at the processor level have a shared secondary cache. An alternative design is shared by all cores processorlevel cache, but this is not necessarily a better design. For example, the shared cache usually es from the physical cache per core, access must be coordinated between the kernel. However, according to Oracle Java SE Mark Reinhold, chief engineer revealed, Java virtual machine consolidation may last a very long time, one is very difficult, the second is to ensure stability, he estimated that require two years to plete, Reinhold also hope to bine all the advantages of both sides, creating a super product. No matter what happens, in order to achieve the best performance and lowest latency, JVM needs to know and support NUMA architectures. For example, by dealing with the hardware, JVM can try a kernel using the hot cache code execution, the socalled hotcache is the data you need is stored inside it. Java EE Oracle has long been a supporter of Java, is also the largest member of the JCP, the pany 10 years ago, has been involved in the preparation of the Java EE specification, so the Oracle Java middleware market to bee predators should not be surprised. Through their own efforts and acquisitions, Oracle Fusion Middleware converging to its own platform. It consists of a full Java EE stack, SOAbased service, an ESB, transaction server and development tool