java programming 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

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

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

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 ("

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

During the interview, algorithm questions are necessary. Through algorithms, we can see a programmer's programming thinking, examine the design and analysis capabilities for complex problems, and reflect the rigor of the problem. Algorithms are a series of clear instructions for solving problems, that is, they can obtain the required output within a limited perio

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

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

The dashed box represents the interface, the solid wireframe represents the entity class, The thick wireframe represents the most commonly used entity classes, the dashed arrows indicate the implementation of the interface, and the implementation arrows indicate that the class can make objects of the class that the arrows refer to. Collection: Allows only one object to be placed in each location. It includes a list of "holding a set of objects in a certain order", and a set that "only allo

] + "|" + seperators [1]; } Else { Regex = "" + seperators [0]; } Words = results. split (regex ); } Public StringnextWord (){ If (pos = words. length) Returnnull; Returnwords [pos ++]; } } 2. Write a program, copy all. java files under the d: \ java directory to the d: \ jad directory, and change the extension of the original file from. java to. jad. (You are

word key that needs to be counted, then take advantage of Java's own indexof () Find the first occurrence of the word position,//statistics plus 1, and the previous statistics of the string truncated, in the remaining fields to match. int times = 0;while (true) {int index = Str.indexof (key), if (Index! =-1) {times++;str = str.substring (index + key.length ( ));} Else{return Times;}}}Operation Result:Source Code 3:Package Com.yue.day11;import Java.util.scanner;public class Yanghuitri {/** * Pri

); System.out.println ("Please enter the lower limit of the number:"); int low = Scanner.nextint (); System.out.println ("Please enter a number cap:"); int high = Scanner.nextint (); if (Low>high) {System.out.println ("you entered the wrong data, please re-enter!") "); System.out.println ("Please enter the lower limit of the number:"); low = Scanner.nextint (); System.out.println ("Please enter a number cap:"); high = Scanner.nextint ();} SYSTEM.OUT.PRINTLN (all primes between low+ "-" +high+ ")

example:What exactly is boxing and unpacking, boxing is that the compiler performs a boxing operation after the underlying type is changed to the corresponding object type, and the reverse is the case. The following blog is a special introduction to Java Boxing and unpacking to share with youHttp://www.cnblogs.com/dolphin0520/p/3780005.html= = and equals I used almost every day, before this I did not care too much about the differences, and later loo

really good programmers and not scare them away, the following issues must be addressed: Really, write, write, code Able to handle things well Reliable A little nerdy, helpful Like to learn new things Based on the above points, I sorted out 10 interview questions. If it was me, as a programmer asked these 10 questions during the

Translated by Peter Seibel/Hao peiqiang This article is an interview with Joshua Bloch, Chief Java architect of Google, by Peter Seibel, expert of commmon lisp, talking about what books programmers should read, how they can quickly get familiar with a new language, and why they choose programming languages is like choosing a bar. 　　 　　Seibel: How did you start