sql interview questions for java developers

multithreaded programs, multiple threads are executed concurrently to improve the efficiency of the program, and the CPU does not go idle because a thread needs to wait for resources. Multiple threads share heap memory, so creating multiple threads to perform some tasks is better than creating multiple processes. For example, Servlets is better than CGI because Servlets supports multithreading and CGI does not support it.How does the volatile keyword work in

Website access?Cache Strategy 14. What MVC Framework technologies can be used in Java? What are their features and applicable environments?Struts, webwork, spring, JSF... 15. What are the advantages and disadvantages of MVC and what are their applicability?The MVC development mode separates the data access layer and data presentation layer, and enables developers to develop a scalable and scalable cont

many occurrences in the array are greater than half @Test public void Test () {int[] num = {1,2,2,2,2,2,2,4,2,4,6,4,2,6,8,2,7,7}; SYSTEM.OUT.PRINTLN (Morethanhaft (num)); } public int morethanhaft (int[] num) {int result =-1; int times = 0, for (int i=0;iTopic Eight:Determines whether an array is the stacking order of another stack @Test public void Test () {int[] num = {1,2,3,4,5};//int[] num1={1,2,3,5,4}; int[] num2={2,1,5,3 , 4}; stackTopic Nine:Draw 5 cards from poker, 0

Today, I found the java interview programming questions in the Forum and thought about it. I found that I forgot my original programming basics. Question: How many equals 2x8 in the most efficient way? Along with the targeted thinking, I thought of 2x8. Later I thought that this efficiency was definitely not the best. think of the concept of a computer system,

1. String S1 = ' 123 ';String s2 = new string ();2. The difference between two ways of implementing multithreadingInheriting the thread and implementing the Runnable interface3. Single-column design mode What's the difference between lazy and a hungry man? * * *Lazy style Features: lazy loading. Delayed loading in multi-threaded security problems, through the addition of synchronization to solve, plus synchronization efficiency is low, with a double-judge method to solve the low efficiency. The

You can only manipulate a type to invert without a generic typeThe code is as follows: Packagecom.swift.fanxing;Importorg.junit.Test; Public classRenyireverse {@Test Public voidTest () {intarr[]=New int[] {1,10,6,9,2}; Reverse (arr); } Public voidReverseint[] arr) { for(inti=0;i) { inttemp=Arr[i]; Arr[i]=arr[arr.length-1-i]; Arr[arr.length-1-i]=temp; } for(intX:arr) {System.out.println (x); } }}Generic functionality can

serialized, then, an output stream (such as fileoutputstream) is used to construct an objectoutputstream (Object stream) object. Then, the writeobject (Object OBJ) of the objectoutputstream object is used) method, you can write the object whose parameter is OBJ (that is, save its status). To restore the object, use the input stream. 55. Can I call non-static methods from inside a static method? A: No. If it contains the method () of the object, object initialization cannot be ensured. 56. When

"Declaration" Source: Power node Java Institute, reprint Source: Script House (The answer to a small number of questions was slightly altered by me) 1, what is the thread local variable. A thread-local variable is a variable within the thread itself, owned by the thread itself, and not shared among multiple threads. Java provides a ThreadLocal class to support t

I was also reading the interview book while learning the video. The record is as follows: 1. LostAfter learning the 2010java high-tech video from Teacher Zhang Xiaoxiang for so many days, he looked at generics, reflection and other things and turned his mind away. He just learned that none of the Main Lines dragged me. That is to say, I am eager to know what major technologies will be required for future development and what is the core of

A database 1. Often ask the database query, modifications (SQL queries include filter queries, aggregate queries and link queries and optimization issues, handwritten SQL statements, such as four team games, with SQL to show all match combinations; Example 2: Select duplicates and then remove duplicates;) How to encrypt passwords in the database (MD5); (1) Passwo

This is the topic discussed during the last interview and is recorded.Spring Why use Spring? What are the benefits of IoC? What are the benefits of scalability? How to instantiate a Bean? What is the difference between ApplicationContext and BeanFactory? How can I read external files through Spring? Can Bean IDS be repeated in the Spring configuration file? What is automatic assembly and type check in Spring? Can ApplicationContext be loaded

directory system that allows applications from other places to leave their own indexes on it to quickly find and locate distributed applications.(3) JMS: it is called Java Message Service and translated into Java Message Service. It mainly implements communication between various applications, including point-to-point and broadcast.(4) JTA: a Java transaction AP

1. What is acitsag startup mode? For such a question, I will write an example myself. I will observe it to understand it. Activty supports four startup modes. Launchmode: Standard: each time a new activity window is started (New Operation) Singletop: if it is a target activity at the top of the stack, It will be opened directly. Otherwise, a new activity window (new) will be opened ). Singletask and singleinstance are basically the same. The difference is that if the root activity is set to sing

Horse Soldier Big Data Architect (1)Link: http://pan.baidu.com/s/1qYTW1m0 Password: LXJDSpring CloudLink: Http://pan.baidu.com/s/1bzG9vK Password: zy2bLink: Http://pan.baidu.com/s/1qXF3eGG Password: 19u9Design and practice of micro-service architectureLink: Http://pan.baidu.com/s/1slNiP5N Password: u6euBEIJING-PK Education Linux Big Data video sharingLink: http://pan.baidu.com/s/1c2Aci6c Password: m7bnStill Academy ~ Internet architect CompleteLink: http://pan.baidu.com/s/1mhJFca0 Password: 25at

executing the Wait,sleep,join method will throw interruptedexception, if the normal state, we can through isinterrupted () =true, To stop the thread from using the return method.(vii) Start and run methods for threadsNote that for a thread to run, only the Start method is executed, this method is the native method, the Run method is where we define the task, and a separate call to the Run method is the same as invoking the normal method. The Start method can only be called once, and more than o

using outer joins, the number of SELECT statements is few;Disadvantage: 1 May load objects that the application does not need to access, wasting a lot of memory space; 2 Complex database table connections can also affect retrieval performance; 5, how to see the SQL that hibernate builds and executes on the console In the file applicationconfig.xml that defines the database and database properties, set the Hibernate.show_sql to TrueThe resulting

This is the topic discussed during the last interview and is recorded. Spring Why use spring? What are the benefits of IOC? What are the benefits of scalability? How to instantiate a bean? What is the difference between applicationcontext and beanfactory? How can I read external files through spring? Can bean IDS be repeated in the spring configuration file? What is automatic assembly and type check in spring? Can applicationco

and attribute value), and information about the server (by passing a ServletContext object)1, with 1-5 working experience, in the face of the current popular technology do not know where to start, the need to break through the technical bottlenecks can add group.2, in the company for a long time, live very comfortable, but job-hopping when the interview hit the Wall. Need to study in a short time, job-hopping to get high salaries can add group.3, if

Controller: When the user clicks the Submit button in the Web page, the controller accepts the request and invokes the appropriate model to process the request. The corresponding view is then called according to the result of the processing to display the results of the processing. MVC process: First the controller accepts the user's request, invokes the corresponding model for business processing, and returns the data to the controller. The controller invokes the corresponding view to

(intx = 0; x ) { - //Invoke function - intnum =getrandom (start, end); - //Output Results - System.out.println (num); in } - } to + /* - * Write a function two explicit: return value type: int argument list: int Start,int end the */ * Public Static intGetrandom (intStartintend) { $ //think back to the random numbers we talked about between 1-100.Panax Notoginseng //int number = (int) (Math.random () * +) + 1;//(int) (Math.r