kafka java example

mechanisms for object-oriented programming code reuse, and the concept of Java polymorphism can be said to be "an interface, multiple methods." Java implements Run-time polymorphism based on dynamic method scheduling, which is a mechanism for invoking overloaded methods at run time rather than at compile time. The overridden overriding and overloaded overloading of methods are different manifestations of

Java memory leaks There are generally two cases of memory leaks. A situation such as in the C + + language, the allocated memory in the heap, when it is not released, erase all Access to this memory (such as pointer redistribution), and the other is to retain the memory and the way it is accessed (referenced) when the memory object is clearly not needed. In the first case, it has been well solved in Java d

Java Reflection detailed This article is still using a small example to illustrate, because I always feel that the case driven is the best, or only to see the theory, read also do not understand, but suggest that after reading the article, in retrospect to look at the theory, will have a better understanding. Start the text below. Case 1 Gets the complete package name and class name from an object

The question of String object construction is often encountered in the oral test. For example, string S = new string ("A"); creates several objects.The following code explains the construction of various strings.The Code is as follows: public class TestConstructString { public static void main(String args[]) { String s1 = "a"; String s2 = "b"; String s3 = "ab"; String s4 = "ab"; System.o

Java Reflection _ A simple example of changing the variables and methods in private Class demotest{ private String name= "123"; Public GetName () { System.out.println (' public getName ' + name); return name; Private GetName2 () { System.out.println ("Private getName2" + name); return name; } As this, change the value of name. How to change. How do I change through

In the Java C/S software development, docking a number of third-party provided web interface. The way you use the interface is not as difficult as you might think.For example, if the provided interface is a get form, the address is output directly on the Web page, and the parameters are pieced together to get the return value.If it is a post interface, it is necessary to make a request for an interface, suc

(abstractclassgenerator.java:219) ... 3 morecaused by:java.lang.OutOfMemoryError:PermGen space at Java.lang.ClassLoader.defineClass1 (Native Method) at J Ava.lang.ClassLoader.defineClassCond (Classloader.java:631) at Java.lang.ClassLoader.defineClass (classloader.java:615) ... 8 more*/Iv. Direct Memory OverflowAlthough allocating memory using Derictbytebuffer also throws a memory overflow exception, it throws an exception when it does not actually request allocation to the operating system, bu

Example of Java socket byte stream transmission, using ocket Server side: Package com. yuan. socket; import java. io. *; import java.net. serverSocket; import java.net. socket;/*** Created by YUAN on 2016-09-17. */public class TalkServer4Byte {private ServerSocket server; private int port = 5020; public TalkServer4Byte () {try {server = new ServerSocket (port);}

Import java. Io. fileinputstream; Import java. Security. keystore;Import java. Security. privatekey;Import java. Security. publickey;Import java. Security. cert. Certificate;Import java. Security. cert. certificatefactory; Imp

The Java serialization and deserialization operations are analyzed in the example. Share to everyone for your reference, specific as follows: Overview: Java serialization refers to the process of converting a Java object into a sequence of bytes, while Java deserialization

Differences between =, equals, and hashcode in Java and the example of rewriting the equals and hashcode methods, using shashcode 1. Override the equals Method Instance part of the code reference http://blog.csdn.net/wangloveall/article/details/7899948 The purpose of rewriting the equals method is to determine whether the content of the two objects is the same (the content can contain many objects, such as

JAVA simple Swing graphical interface application example JAVA simple Swing graphical interface application example Package org. rui. hello; import javax. swing. JFrame;/*** simple swing window * @ author lenovo **/public class HelloSwing {public static void main (String [] args) {JFrame frame = new JFrame ("hello S

Java basics-a simple example of JDOM operations-general Linux technology-Linux programming and kernel information. The following is a detailed description. The openness of JAVA attracts many companies and individuals to constantly improve JAVA's performance. JDOM is the creation result of two famous Java developers and

To implement dynamic proxy through JDK, classes with proxy requirements (called implementation classes) must implement interfaces. The dynamic proxy can segment the logic and implement the logic through the proxy generation. Other operations can be performed during this period. JDK's dynamic proxy mainly involves two classes in the Java. Lang. Reflect package: proxy and invocationhandler. Invocationhandler is an interface that defines the cross-cuttin

Java is a kind of object-oriented programming language that can compose Cross-platform application software. Java technology, with its superior versatility, efficiency, platform portability and security, is widely used in PCs, data centers, gaming consoles, science supercomputers, mobile phones and the Internet, and has the world's largest developer professional community. public void Serve () throws Inter

Java SPI mechanism and simple example, callback PI Mechanism I. SPIMechanism Here we will first describe the concept of SPI. In English, a single SPI Service Provider Interface can be literally understood as a Service Provider Interface, just as a Service Provider Interface can be understood from the SPI name; my SPI definition: interfaces used by developers who provide services with vendor and extended fra

maintain a list of which memory blocks are available, and at the time of allocation, find a large enough space in the list to be partitioned to the object instance and update the records on the list. In addition to how to divide the available space, there is another issue to consider, object creation is very frequent behavior, in the concurrency of the thread there is a security problem,Two solutions: 1. Synchronizing actions for allocating memory space2. The actions of the memory allocation ar

(String x) {5: return("Hello my friend, " + x + "! Glad to see you!");6: }7: } It is easy to add any comments. To compile it, you only need to use the following command: javac SOAPService.java Step 2: Once we have prepared the soap service, we need to deploy it using the soap Service Manager. This can be implemented in many ways, but in order to make it easier for beginners to understand soap, I provide the easiest way. Assume that your web server (tomcat or other) is running properly and

is used to process the task.When many tasks are processed:Core Thread corePoolSize, task queue workQueue, and maximumPoolSize. If all three are full, handler is used to process the rejected task.When there are few tasks to process:When the number of threads in the thread pool is greater than corePoolSize, if the idle time of a thread exceeds keepAliveTime, the thread will be terminated. In this way, the thread pool can dynamically adjust the number of threads in the pool. Step 2 (CODE)

Address of the remote machine. Test result can be verified on the default TestNG report generatedSummary Selenium Grid is used to run multiple tests simultaneously on different browsers and platforms. Grid uses the Hub-node concept. The hub is the central point wherein you load your tests. Nodes is the Selenium instances that'll execute the tests that's loaded on the hub. To install Selenium Grid, need to download the Selenium Server jar file-the same file used in runni