java spring interview questions

default branch, which must be the last branch of a switch statement. (3) default is executed when no case statement is equal to the value of the variable. The default branch does not require a break statement.Break is used to interrupt the loop statement, and continue is used to continue the loop. Breake break out of the loop body, continue continue the next loop, but the statement after continue is not running. Continue can only be used in loop statements, and break may be used in other branch

As a Java programmer who is often asked in an interview, let me summarize some of the questions that I often don't ask. The difference between 1.HashMap and Hashtable Often asked. Both are classes of the map interface, which enable you to map a unique key to a specific value. HashMap class is not sorted and can have a null key and multiple nul

configuration. While JavaScript is interpreted to perform without generating intermediate files, "read a sentence, execute a sentence", the execution can generally be done in three ways:1. The general browser comes with the JS interpreter, which can be used directly by the browser;2. Special interpreter software can be installed node. js, executing the. js file;3. Executed with the Web page, using the Third, the data typeJava is a strongly typed language, and when it comes to data, the declarat

Java multi-thread interview questions 1. What is the difference between ArrayList and Vecoter? Similarities and differences between Array and ArrayListI. Differences between Array and ArrayList#1. variables of the Array type must be instantiated at the same time (at least the size of the Array must be initialized), while ArrayList can only be declared first.For e

The resume has some Ajax and struts issues.Growth strategy for database primary keyThe type of struts?Why use the difference between struts;session and cookies,Introduction to AjaxWhat are the built-in objects for 1.jsp?Four scopes for 2.jsp3. "". What is the difference between equals A and A.equals ("")?What is the difference between get and post for a 4.form form submission?What is the difference between 5.Cookie and session?How do 6.mysql and Oracle's primary keys come into being?7. Why use S

-threaded access to shared resources, due to improper access, usually a thread locked a resource A, but also want to lock resource B, and in another thread, the lock resource B, but also to lock resource A to complete its own operations, two threads want the other's resources, Instead of releasing their own resources, two of threads are waiting for a situation that cannot be performed.Java Network Programming approximate process:UDP programmingSend side:1, create the Socket object constructor Da

position, filling the original AI (i), the AI value inserted into the space after the shift of J * * This implementation of a card from I, inserted into the exact position. Loop through the process sequentially, and each element of the loop is eventually inserted into the position it should be in, thus sorting is achieved. * [1, 2, 4, 5, 6, 7, 9, 3, 8] * [1, 2, 3, 4, 5, 6 , 7, 9, 8] * @param array * @param up */Public static void Insertsort (Int[] Array, Boolean up) {for

(); - } - - Public BooleanIsEmpty () {///Bottom call is LinkedList's IsEmpty () method to determine if the set internal data is empty - returnlink.isempty (); in } -}(2) test of Mystack:1 Packagecn.itcast_05;2 3 /*4 * Test of Mystack5 */6 Public classMystackdemo {7 Public Static voidMain (string[] args) {8 //To create a collection object9Mystack ms =NewMystack ();Ten One //adding elements AMs.add ("Hello"); -Ms.add ("World"); -Ms.add ("

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

rewrite the aof file, the performance impact of this persistence is minimal, but the aof file will continue to grow, aof file over the General Assembly to affect the recovery speed of master restart. Master should not do any persistent work, including memory snapshots and aof log files, in particular, do not enable memory snapshots to persist, if the data is more critical, a slave open aof backup data, the policy is synchronized once per second. Master calls bgrewriteaof rewrite aof file, a

Java multithreading interview questions Induction1. What are the implementation methods for multithreading? The following example shows the thread synchronization. (1) Java multithreading has two implementation methods: Inheriting the Thread class and implementing the Runnable interface. Thread implements the Runnable

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

Java Algorithm interview questions: Write a Singleton, javasingleton Package com. swift; public class Singleton {public static void main (String [] args) {/** write a Singleton */ORC_Hungry.getOrc (). fun (); ORC_Lazy.getOrc (). fun () ;}} class ORC_Hungry {// hungry Chinese private static ORC_Hungry orc = new ORC_Hungry (); private ORC_Hungry () {} public stati

longer executed.(2) But in the case of a hash collision, the first two conditions are established, and then the last equals must be used to determine the equality of the objects.A 3.hash collision scene?(1) Generally appears in large data situations(2) The generation method of Hashcode is weak (such as the artificial production hashcode above)Summary: This chapter mainly through the introduction of hash collision once again in-depth understanding of hashmap work principle.This chapter is here,

1. The difference between String and StringBufferThe Java platform provides two classes: string and StringBuffer, which can store and manipulate strings, That is, character data that contains more than one character. This string class provides values that cannot be changed strings and the strings provided by this StringBuffer class are modified when you know that character data is going to change, you can use StringBuffer typically, You can use Stri

Difference between Forward and Redirect in common JAVA interview questions, forwardredirect The user sends an HTTP request to the server, which may be returned to the user after being processed by multiple information resources. Each information resource uses the request forwarding mechanism to forward requests to each other, however, the user does not feel reque

interview. Although the Servlet, JSP, JSF, JPA,JMS,EJB, and other Java EE technologies are not covered here, there are no mainstream frameworks such as Spring mvc,struts 2.0,hibernate, nor do they contain SOAP and RESTful web Service, but this list is also useful for Java developers who are ready to apply for