how to write microservices in java

point four: Flush () and close ()Flush () is the contents of the write buffer all "spit" to the file, if not, it is possible that a lot of content is still in the write buffer, not in the file, that is, there is a loss of possible.Flush () is called in close (). It is a real sign of file completion, the file content after the completion of the file stream does not close, will lead to some "weird" problems.

requested and freed after being used. In a non-fair lock, the order in which the thread obtains the lock is indeterminate. It is possible to downgrade a write thread to a read thread, which in turn cannot be (deadlock).Similar to Reentrantlock, a write lock in Reentrantreadwritelock can have only one holder, and only the obtained thread is freed. A read lock in Java5.0 is more like a semaphore than a lock,

Java read PHP write memcache content Story background: I use Java to insert a digital record, read in PHP can not read correctly. Today found that if you use memcachedclient to insert a number, or Java objects, then in PHP is garbled. Objects can be understood, simple numbers will be garbled Such as Th

given as a reference in the next section.Summarize With the understanding of UMT, explicit management of transactions using UMT can have better performance. When you want to use CMT for transaction management, you can make the scope of a transaction smaller by dividing the method into multiple methods. JPA Write OptimizationsIn JDBC, there are two key performance optimization methods: Reusing PreparedStatement objects

The following example shows the built-in reentrantreadwritelock instance in the Java API concurrent library.Class cacheddata {object data; volatile Boolean cachevalid; reentrantreadwritelock RWL = new reentrantreadwritelock (); void processcacheddata () {RWL. readlock (). Lock (); // @ 1 If (! Cachevalid) {// must release read lock before acquiring write lock RWL. readlock (). unlock (); // @ 4 RWL. writelo

does not belong to itself or does not exist.The previous chapters have repeatedly emphasized that for shared locks, it is not the concept of locks, more like the concept of a counter. A shared lock is relative to a counter operation, one acquisition of a shared lock is equivalent to a counter plus 1, releasing a shared lock is equivalent to a counter minus 1. Obviously only a thread holds a shared lock (that is, the current thread carries a counter that describes how many shared or multiple sha

1. PrefaceThe singleton (Singleton) should be the most familiar design pattern for developers, and it seems to be the easiest to implement-basically every developer can write it out-but is that really the case?As a Java developer, you may feel that you have enough knowledge of the singleton pattern. I do not want to alarmist say there must be something you do not know-after all, my own understanding is real

1. PrefaceThe singleton (Singleton) should be the most familiar design pattern for developers, and it seems to be the easiest to implement-basically every developer can write it out-but is that really the case?As a Java developer, you may feel that you have enough knowledge of the singleton pattern. I do not want to alarmist say there must be something you do not know-after all, my own understanding is real

One: Cause(1) Before processing text data, all kinds of cleaning data are used in Java File,filereader/filewriter,bufferedreader/bufferedwriter class, see Java Read-write text file(2) Java is used because the map in Java is very flexible, the Eclipse compiler is more force,

We use java to write data and then use php to read data. However, when we use php to read data, we find the memcache garbled code problem. Next, I will introduce the solution to memcache garbled code. Java reads php and writes memcache content Background: I inserted a digital record in java and could not be correctly r

1. IntroductionThe full name of MVC is the model View Controller, which is the abbreviation for the models-view-controller, a software design paradigm that organizes the code with a method of business logic, data, and interface display separation. Aggregating business logic into a single component does not require rewriting business logic while improving and personalizing the interface and user interaction. MVC is uniquely developed to map the traditional input, processing, and output functions

The previous properties article has described the basic usage of the Java configuration file class properties, and when viewing the Help documentation for the JDK, there are also two methods in the Properties class LoadFromXML (InputStream) and S Toretoxml (OutputStream, String, String), the XML in the method name is not difficult to determine that the two methods are read/write data to an XML file, respect

(newPath, "rw"); FileChannel fcw = raw. getChannel (); MappedByteBuffer mbbw = fcw. map (FileChannel. mapMode. READ_WRITE, 0, length); for (int I = 0; I The first is the read/write time using file ing. The second is the time used by the file Channel to read and write files. Time consumed by the Third bit BufferedInputStream Channel is used for multiple tests. File ing and read/

respectively. So the amount of data a disk can store is:512 * 18 * 80A floppy disk has two disks, so the data a floppy disk can store is:2 * * * * * = 1474560 Byte = 1440 KB = 1.5MNext, we use Java to simulate a 3.5-inch floppy disk, and its read-write logic.Floppy.java for implementing virtual floppy disksImport Java.io.dataoutputstream;import Java.io.fileoutputstream;import Java.util.arraylist;import Jav

releasing the read lock. Lock get Interrupt Both the read lock and the write lock support the acquisition lock during the outage. This is consistent with the exclusive lock. Condition variable The write lock provides support for the conditional variable (Condition), which is consistent with the exclusive lock, but the read lock does not allow the conditional variable

the initial capacity is not set, the system will be expanded by 1.5 times times the rule, each expansion is a copy of the array, if the volume of data is large, such copies will be very resource-intensive and inefficient. So, if we know the possible length of a ArrayList, then setting an initial capacity on ArrayList can significantly improve system performance.Other sets such as vectors and ArrayList similar, only the expansion of multiples of different, vector expansion twice times, we are in

abstract class is a super class that represents all the classes of the output byte stream. The output stream accepts the output bytes and sends them to a receiver. Applications that need to define the outputstream subclass must always provide at least one method that can write one output byte. Void close ()Close the output stream and release all system resources related to the stream.Void flush ()Refresh the output stream and forcibly

There are three ways to do image I/O in Java (that is, to read pictures and write pictures, without involving complex image processing):1. The Java image I/O API, which supports common images, has been built from Java 2 version 1.4.0.Home: http://java.sun.com/javase/6/docs/technotes/guides/imageio/index.html2. Image I/

business trip and the date on which the business trip ends. Each field is distinguished by space, for example:Zhang San 2010-9-17 2010-10-15Li Si 2010-9-5 2010-10-30Wang Wu 2010-9-20 2010-11-2Based on the above information, calculate the number of travel days for each person, and use the license fee to write the result to D: \ test \ result.txt. the content of result.txt includes the name of the person on which the business trip ends and the number o

) System variable path path specifies an. exe fileSystem variable Classpath path Specifies the. class fileAfter you configure a system variable, you can execute it in any directory of CMD, the file you want to execute(9) CMD command line executable all. exe file------(parameter value setting for desktop shortcut)(10) When defining the class name, the first letter of each word must be capitalized,public static void Main (string[] args) {} Javac.exe compile error codes (such as Mian) without error