java object oriented interview questions

Today in a company (not disclosed) wrote a set of Java face questions. There is a question about this. Which design pattern used in Java.lang.Runtime? So what design pattern is used in the java.lang.Runtime? And what design patterns are used in java.utils.collection. At that time because of this unpopular knowledge not enough, and the API also read less, so a short answer. back home and searched the ne

The following content is the original Java surface of the online question set and the answer after a comprehensive revision of the responsible questions and answers, the original topic has a lot of repetitive topics and worthless topics, there are many reference answers is also wrong, modified Java surface Test set reference the latest version of the JDK, removed

(); - } - - 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 ("

. Object-oriented computing begins with the basic concept that the real world can be depicted as a series of completely autonomous and encapsulated objects that access other objects through a protected interface. 4. Polymorphism: allows different types of objects to respond to the same message. Polymorphism includes parameterized polymorphism and inclusion polymorphism. The polymorphism language has the adv

"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

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-hopp

Java Algorithm interview questions: Read all names from text files similar to the following, print duplicate names and repeated times, and sort by repeated times; read docx and read doc. Use the poi jar package to provide download, Read all names from text files similar to the following, print duplicate names and repeated times, and sort by repeated times 1, Zhan

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,

Java Questions Answers 1. What is the difference between an applet and an application? A Java application is made up of a main () method declared as public static void that accepts a string array argument, along with any other classes that main () CILS. it lives in the environment that the Host OS provides. A Java a

A few days ago in the Java interview problems encountered, this is only part of the problem, there are many questions in the interview about data structures and algorithms. Here to summarize, hope that the ability of people can try to do, and in the comment area to leave your answer, let everyone learn from each other.

Sword refers to the Java Implementation of offer programming questions-interview question 5 prints the linked list from start to end and offer from end to endTopic Description * sword refers to offer interview question 5: print the linked list from the end to the endEnter the head node of a linked list and print the va

Design a method for java interview questions to obtain random numbers in any range. When learning java basics, you may listen to the random numbers between 1 and 100 at most, so we should first write a random number between 1 and 100. The Code is as follows, public class MathDemo1 { public static void main(Str

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

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

. 28th, Programming question: Calculate 2 times 8 in the most efficient way? Programmers with a C background are particularly interested in asking such questions. 2 29th, two object values are the same (x.equals (y) = = true), but can have different hash code, this sentence is correct? No, there's the same hash code. 30th, when an object is passed as a param

Java Algorithm interview questions: Separate them with carriage return or space in the answer file ., Package com. swift; import java. io. bufferedReader; import java. io. bufferedWriter; import java. io. fileInputStream; import

Java interview questions: how to sort HashMap key values In Java, HashMap is a data structure used to store "key" and "value" Information pairs. Unlike Array, ArrayList, and lists, it does not maintain the order of inserted elements.Therefore, sorting HashMap Based on keys or values is a very difficult

two bytes, so a char variable is also occupied by two bytes. Two Java Basics 1. Talk about polymorphic forms of expression. (1) Overloading, overriding, overloaded overload means that there can be multiple methods with the same name in the same class, but the argument lists for these methods are different (2) overriding override means that a method in a subclass can be exactly the same as the name and parameters of a method in the parent class. When

Huawei's Java interview questions Question No: 1 1. Public class test { Public static void changestr (string Str ){ STR = "welcome "; } Public static void main (string [] ARGs ){ String STR = "1234 "; Changestr (STR ); System. Out. println (STR ); } } Please write the output result: Question No: 2 1. Public class test { 2. Static Boolean Foo (char c ){ 3. syst

Sword refers to Java Implementation of offer programming questions-the integer power of the value of interview question 11, and sword refers to offer Question: Implement the double power (double base, int exponent) function to calculate the power of base's exponent. Do not use library functions, and do not need to consider large numbers. Solution: the most common