J2se 1.5 In a nutshell Chinese Version
2004-03-22 CLICK: 104
J2se 1.5 In a nutshell Chinese Version
Article[H2] j2se 1.5 In a nutshell [/H2]--------------------------------------------------------------------------------According to the Translator's note: the understanding of the new featu
In a nutshell:
-Monitor. Enter/exit and mutexes are commonly used for protecting objects
From being used by two threads at the same time. Every thread acquires
Mutex (resp. enters the monitor) before it uses the object, and no other
Thread will be allowed to do the same until the mutex is released (resp.
Monitor is exited); the monitor methods are faster and use less memory,
Mutexes can be shared using SS Processes
-The lock statement internally uses
Preface
I recently read the book C #3.0 Core Technology in the library. I think it is quite good to read it. C #3.0 technology covers from basic syntax to new features, it is a good book to learn C #3.0. I wanted to download the electronic version from the Internet but couldn't find it, but I read the English version of C #3.0 in a Nutshell, 3rd Edition, also very good. I plan to take the time to learn something and write a few articles on my blog to
publishing.Vbsctip: Is the ASP default scripting language.LUA: is a small scripting language.Haskell: A standardized, general-purpose, purely functional programming language with unqualified semantics and strong static types.LOGO: is an early programming language and a programming language very close to natural language.ML: is a general-purpose functional programming language.Pascal: It's a high-level programming language for computers.Prolog: is a logical programming language.Scheme: A variant
1. What's delegate in C #?A delegate is an object, that knows how to call a method.A delegate type defines the kind of method that delegate instances can call. Specifically,It defines the method ' return type and its parameter types.The Followingdefines a delegate type called Transformer:delegate int Transformer (int x);Transformer is compatible with any method with an int return type and a singleint parameter, such as this:static int Square (int x) {return x * x;}Assigning a method to a delegat
-id of this router in the Hello package
Exstart: The initial state of information exchange, determine the master-slave relationship, who first initiate the exchange, determine the DD message sequence number.
Exchange: Information exchange status, the interaction of DD messages
Loading: Information loading status, exchanging LSA information via LSR, LSU
Full: Fully contiguous state
X. ROUTER-ID: Manual designation is the highest priority, if not manually specified, the active
locked.
Locking an object[] doesn ' t lock the individual objects.Locks a object[] array, and cannot lock every object within the array.
Primitives is not mutable, so they can ' t (and don ' t need to) be locked.Native types are immutable, so they cannot (and do not need to) lock.
Synchronized can ' t appear on a method declaration in an interface.Synchronization cannot appear on the method of an interface.
Inner classes is just syntactic sugar, so locks on Inner classes has n
distinguish between these, kinds of equality. One of the "identical" when talking about equality of references and the word "equal" when Talking about a distinct objects that has the same content. To test-nonidentical objects for equality, pass one of the them to the Equals () method of the other:
All objects inherit a Equals () method (from Object), but the default implementa‐tion simply uses = = to test for identity of references, not equality of content. A classThat wants-to-allow ob
to appear and replace, in the programming in fact many places are embodied, most oftenSee mapI don't quite understand why I wrote it until I saw the author's description in the book.Synthesis and aggregation principles, in fact, better words are combinatorial and aggregation, and now many concepts of the boundaries are actually not so standard or strict, we will inherit and hold,is generally held limited, holding is holding an instanceIn short, a succession of the birth of countless situations,
MySQL, Mysqli, PDO in a nutshell comparison
1
MySQL extension
(Note: original, poor)
2
MYSQLI extensions (process-oriented)
(Note: More features than above)
3
Mysqli extension (object-oriented)
(Note: More in line with object-oriented thinking than above)
4
Mysqli extension (Object-oriented) (Prepare statement)
(Note: More performance and safety than
1, bytecode is always a big paragraph2, other languages run in Java, or implement a compiler similar to Javac, which interprets the language as a class file. Either, directly re-implementing the JVM, directly explaining the language3,java and C + + differences:
Java's function call is virtual by default
Java always passes the value of the
Java does not support multiple inheritance
Java does not have operator overloading
4,java ignores all whitespace, tab, line breaks, and so on,
The relationship between the JAVA8 function reference and the lambda expression => function Reference is a simplified lambda expression that infers only the function, parameter, and return value compiler that appears. > Actually this grammar and lambda expression is exactly the opposite, NBSP;LAMBDA expression represents an anonymous method, which is the absence of a function name, giving only parameters and method bodies. Then the existing function comes in handy, the existing function has th
Install times wrong: Failed to execute goal org.apache.maven.plugins:maven-antrun-plugin:1.7:run (site) on project Hadoop-hdfs:an Ant B Uildexception has occured:input file/usr/local/hadoop-2.6.0-stable/hadoop-2.6.0-src/hadoop-hdfs-project/ Hadoop-hdfs/target/findbugsxml.xml
Hadoop Foundation----Hadoop Combat (vi)-----HADOOP management Tools---Cloudera Manager---CDH introduction
We have already learned about CDH in the last article, we will install CDH5.8 for the following study. CDH5.8 is now a relatively new version of Hadoop with more than hadoop2.0, and it already contains a number of
there is no interference between them too much.g) The first problem to solve are hardware failure:as soon as you start using many pieces of hardware, the chance that one Would fail is fairly high.The first problem to solve is a hardware failure problem: As long as you use a multi-part integrated device, there is a very high chance that one of the parts will fail.h) The second problem is a most analysis of the tasks need to being able to combine the data in some a, and data read from one Disk ma
Chapter 2 mapreduce IntroductionAn ideal part size is usually the size of an HDFS block. The execution node of the map task and the storage node of the input data are the same node, and the hadoop performance is optimal (Data Locality optimization, avoid data transmission over the network ).
Mapreduce Process summary: reads a row of data from a file, map function processing, Return key-value pairs; the system sorts the map results. If there are multi
1. Hadoop Java APIThe main programming language for Hadoop is Java, so the Java API is the most basic external programming interface.2. Hadoop streaming1. OverviewIt is a toolkit designed to facilitate the writing of MapReduce programs for non-Java users.Hadoop streaming is a programming tool provided by Hadoop that al
Not much to say, directly on the dry goods!GuideInstall Hadoop under winEveryone, do not underestimate win under the installation of Big data components and use played Dubbo and disconf friends, all know that in win under the installation of zookeeper is often the Disconf learning series of the entire network the most detailed latest stable disconf deployment (based on Windows7 /8/10) (detailed) Disconf Learning series of the full network of the lates
Directory structure
Hadoop cluster (CDH4) practice (0) PrefaceHadoop cluster (CDH4) Practice (1) Hadoop (HDFS) buildHadoop cluster (CDH4) Practice (2) Hbasezookeeper buildHadoop cluster (CDH4) Practice (3) Hive BuildHadoop cluster (CHD4) Practice (4) Oozie build
Hadoop cluster (CDH4) practice (0) Preface
During my time as a beginner of
Wang Jialin's in-depth case-driven practice of cloud computing distributed Big Data hadoop in July 6-7 in Shanghai
Wang Jialin Lecture 4HadoopGraphic and text training course: Build a true practiceHadoopDistributed Cluster EnvironmentHadoopThe specific solution steps are as follows:
Step 1: QueryHadoopTo see the cause of the error;
Step 2: Stop the cluster;
Step 3: Solve the Problem Based on the reasons indicated in the log. We need to clear th
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.