java practice book

outstanding open source Concurrency Toolkit, java.util.concurrent, which contains mutex, trust, and performance-performing collection classes such as queues and hash tables, and some work queue implementations under concurrent access. The Pooledexecutor class in this package is an efficient, widely used, and correct implementation of a thread pool based on a work queue. Instead of trying to write the code yourself, it's easy to make mistakes, and you can consider using some of the tools in the

Java Theory and Practice: Concurrent collection Classes util.concurrent In addition to many other useful concurrent building blocks, the Douglea package contains some of the major collection types List and Map high-performance, thread-safe implementations. In this month's Java theory and Practice ,

DatabaseService mysqld Restart//Restart MySQL databaseNetstat-NTLP //See if MySQL port is 3306I use the local test remote connection, the author is using the Mysqlworkbench client if not connected, remember to switch off the firewall under the test service iptables Restart/stop/start switch off the firewall can be connected, it is the port problem scheme1/sbin/iptables- I.INPUT- PTcp--Dport3306 -jACCEPT//Open port: 3306/etc/rc.D/init.D/iptables Save//Save/etc/init.D/iptables restartorService I

-agent to create perf-pid.map text files. This file lists the 16-binary symbolic address, size, and symbol name. Then, from 2009 onwards, the Perf_events tool in Linux added support for JIT symbols. The tool examines the/tmp/perf-pid.map file to complete the check of symbols from the language virtual machine. For the second aspect, the JVM adds a new option,-xx:+preserveframepointer. With the efforts of Zoltán, Oracle and other engineers, the latest JDK9 and JDK8 have added this option to save t

Time: 32 Time: 15 3 Time: 50 Time: 57 Time: 39 Time: 21 4 Time: 47 Time: 31 Time: 39 Time: 14 Can be summarized as follows: Iterate keys and search values very inefficient, ranked almost in the penultimate or second For-each Iterative entries performance is best, but cannot remove For-each iterative keys and values are no more than For-each iterative entries performance (about Fast 10%),

Recently made a technical blog site, organized a study of the Java process to do examples and small projects, are placed on the site to provide download, there are examples of beginners, there are Java Web examples, as well as my university during the graduation design source, can be downloaded.Address: micro-Child blog-java Novice

to be met, simplicity, and performance. There is often a mutual constraint between simplicity and performance. When implementing a synchronization strategy, be sure not to blindly sacrifice simplicity for performance (which could compromise security). When using a lock, you should be aware of the functionality implemented in the code block and whether it will take a long time to execute the code block. Whether you are performing a computationally intensive operation or performing

Friday free to do nothing, based on an analysis of the 12306 ticketing algorithm (Java version) theory, the Java coding practice for your readers reference (the following is a brief description of the relevant code) 1. Booking tool category 1.1 The ticket information of the initialization of a train compartment /** * Generate Ticket information * * @par

dynamically invoking objects using reflection, such as a Addsaray method in the employee class, we look at how to invoke:Class C3 = Class.forName ("Employee"), Object E3 = C3.newinstance (); Field Fsaray = C3.getdeclaredfield ("Saray"); Fsaray.setaccessible (true); Fsaray.set (E3, 10000); System.out.println (Fsaray.get (E3)); Output 10000//get Methodmethod m = C3.getdeclaredmethod ("Addsaray", double.class);/* * Method m = C3.getdeclaredmethod (" Addsaray "); Method m2 = * C3.getdeclaredmethod

-h option for top is clearly stated: All thread information below this process will be printed. That is, a program that launches multiple threads, the next thread in Linux will correspond to a process!At this point, we can use Jstack to further analyze the thread's dump file:650) this.width=650; "src=" Http://s2.51cto.com/wyfs02/M00/7E/D5/wKioL1cKJhiDetsKAACWujw9FVA711.png "title=" Sogou _ 2016-04-10_17-59-49.png "alt=" Wkiol1ckjhidetskaacwujw9fva711.png "/>We can easily get the names of these t

) Instantiation (in the case of an inner class, pay particular attention to the instantiation method, which can be referenced by using new and reflection to produce an instantiated object of the Java inner Class) Sign in to map Static{Reflections Reflections =NewReflections ("Prepare");//Package name, can reduce the search scopeset for(classintIDX = Typename.lastindexof ("$");//inner class scene intIDX1 = Typename.lastindex

) { System.out.println ("---" +invokername+ "----" +adb); } } The output is:---452345234----q31234132 Articles you may be interested in: Analysis of private attribute inheritance problem in PHP class Query for private access control in PHP classes and objects public,private,protected Differences in PHP class and example analysis An analysis of PHP object-oriented public private protected access modifier is the private modifier in Java