Java

1. Variable and non-changeableThe string class uses a character array to hold strings, as follows, because there is a "final" modifier, so you know that the string object is immutable. Each time a change is made to a string object, it is equivalent

Goal:1, with a solid Java foundation, the data structure, basic algorithm proficiency, and have the basic algorithm design capabilities.2, front desk: Proficient in Jsp/servlet, HTML, JavaScript, Ajax, Jquery, XML, JDBC and other web development

Now there are a lot of articles about the Java Collection class, but I recently saw a very interesting picture, basically to show the overall framework of the Java collection, very intuitive.If you find the picture is not clear, click here to see a

Package com.jckb;/** Select Sort * * @author GX * Algorithm principle: * The first number and the following each number is compared, if it is greater than the number of subsequent position exchange, * The first comparison ended after the minimum

Packagecom.jckb;/*** Bubble Sort *@authorGX*/ Public classBubblesort { Public Static voidMain (string[] args) {int[] arr = {6, 3, 8, 2, 9, 1}; for(inti = 0; i ) { for(intj = 0; J ) { if(Arr[j] > arr[j + 1]) {

To avoid scenarios where consumption results need to be stored in a relational database and consumer continue to consume when the database is downhttp://kafka.apache.orgCheck a lot of source code are recorded, save the next time to filter the source

1. Vilatile, lock and atomic operationsThese three are the basis for understanding Java concurrency.In simple terms, Vilatile modified variables can ensure that all threads are visible to them, and that the mechanism is actually dependent on atomic

Here, let's introduce the process of Java calling an instance of WebService.This project cannot be run because the interface address is not available.This is just to introduce a process, while leaving your own notes. If you want to learn, you can

When the project is released into the network, the host (such as IP address 192.168.10.88) accesses the URL of the LAN server, such as http://192.168.10.142:8080/index/, with request.getremoteaddr ( the host IP address obtained is 192.168.10.142,

Packagecom.test.collection;ImportJava.util.HashMap;Importjava.util.Hashtable;ImportJava.util.Map;ImportJava.util.concurrent.ConcurrentHashMap;//Basic application of Map Public classMaptest {/** * @paramargs*/ Public Static voidMain (string[]

In Java, exception handling and throws are handled by Java.First, we need to know what exceptions are? It is often said that your code may have no errors during compilation, but exceptions may occur during runtime. For example, a common NULL pointer

Special Class for random file read/write -- RandomAccessFile, randomaccessfileThe RandomAccessFile class can read files randomly, but it is not useful in testing;File can be used to test whether a File exists or not;The FileWriter class can

After the from form submits data, the background object cannot accept the value. If, in the SSH framework, a null value is displayed in the background object after the data is submitted through the from form on the previous page, that is, the value

[Spring] Spring MVC analyzes the transmission of Date data, springmvcdate Add the following code to the Controller: @ InitBinderpublic void initBinder (ServletRequestDataBinder bin) {SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd HH: mm:

Nginx adds the nginx_heath module, nginxnginx_heath Why? Why the nginx_heath module is used, for example, when nginx + tomcat is deployed, nginx-> upstream polling can be used to kill the suspended tomcat service after tomcat is suspended, if the

Xml loading prompt: Error on line 1 of document: content is not allowed in the preface. xmldocument I did related tests in java. First, I pasted the following error: Read the xml configuration file xmls \ property. xmlorg. dom4j. Disable

Role and usage of ModelMap in Spring MVC, mvcmodelmap Role of ModelMap: ModelMap objects are mainly used to pass control methods to pass data to the results page. Similar to the setAttribute method of request. Therefore, to obtain data on the jsp

In hibernate, how does one solve the problem of converting objects to json endless loops in multiple relationships? hibernatejson Write down the reason first! I am writing an SSH project. The problem I encountered in the project is to convert the

Six rules changed by programmers and six rules changed by programmers At the 2016 agile conference, Esther Derby discussed six rules for programmers to transform, to respect everyone, to acknowledge the complexity of changes, and to inspire

Mybatis Learning (1), Mybatis Learning (1) import the pom file first   4.0.0 Mybatis com.mybatis war 0.0.1-SNAPSHOT com.mybatis Maven Webapp http://maven.apache.org org.mybatis mybatis