java 7 interview questions

Transferred from: http://icyfenix.iteye.com/blog/715301The background of this post is tonight to see JE on this posting: http://www.iteye.com/topic/715256, the words written on impulse, if you can, can have other interviewers to analyze their interview questions asked, it may be a very meaningful thing. In the company as a technical interviewer for a few years, from graduating students to work more than 10

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

threads are not able to modify objects in the collection that is being traversed by iterator. At the same time, iterator allows the caller to delete elements from the underlying collection, which is not possible for enumeration.What is the difference between 17.HashSet and TreeSet?HashSet is implemented by a hash table, so its elements are unordered. The time complexity of the add (), remove (), contains () method is O (1).On the other hand, TreeSet is implemented by a tree-shaped structure in

In the Java Pure Grammar interview, mainly encountered some of the basic interview questions, summarized here!First, to talk about final, finally, finalize the difference. final-modifier (keyword) If a class is declared final, it means that it can no longer derive a new subclass and cannot be inherited as a parent c

into the corresponding method to invoke the logical layer of the method to achieve response to the customer.There are no doget, dopost, and so on in the Servlet interface and Genericservlet, these methods are defined in HttpServlet, but all return error information, so, each time we define a servlet, Must implement these methods such as Doget or Dopost.Each custom servlet must implement the Servlet interface, and the Servlet interface defines five methods, of which the more important three meth

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

Sword refers to Java Implementation of offer programming questions -- interview question 13 deletes linked list nodes in O (1) time, and sword refers to offer Question: given a one-way linked list head pointer and a node pointer, define a function to delete the node at O (1) time. Given a one-way linked list, the time complexity of normal Chain List deletion is t

Java programmer interview questions (86-115) 86. In Struts 2, how does Action obtain the data that the user inputs from the page, and how does it transmit its own data to the view? A: There are three ways for Action to retrieve data from the page: 1) accept parameters through the Action attribute 2) obtain parameters through the domain model 3) ModelDriven )

Analysis:Store basic data types1. Create an arr reference in the stack2. Create an int array of length 3 in the heap and initialize it, assigning the default value of 03. Point an ARR reference to an int array4. Re-assign values to each int value in an int arrayStore reference type User1. Create a Userarr reference in the stack2. Create a user array of length 3 in the heap and initialize it, assigning a default value of NULL3. Point the Userarr reference to the user array4. Create a user1,user2

Java interview questions: Implementation of stacks and queues During the interview, stacks and queues are often checked in pairs. This article includes the following stack and queue test content: 1) stack Creation 2) create a queue 3) Two stacks implement one queue 4) two queues implement one stack 5) design the stack

(throughput) collector?The throughput collector uses a parallel version of the new generation garbage collector, which is used for medium-sized and large-scale data applications. The serial collector is sufficient for most small applications, which require about 100M of memory on modern processors.7. In Java, when can objects be garbage collected?This object can be recycled when the object becomes inaccess

Analysis of Java interview questions and prevention of SQL injection, semi QL This article focuses on a common question in the Java interview questions, how to judge and prevent SQL Injection problems. The details are as follows.

. At the same time if there are multiple threads accessing Hashmap,collections.synchronizedmap () can be substituted, generally hashmap more flexible.10. Why is the vector considered to be obsolete or unofficially deprecated? Or why we should always use ArrayList instead of vectors.You should use ArrayList instead of vectors because by default you are non-synchronous, vectors synchronize each method, you almost never do that, and usually you want to synchronize the entire sequence of operations.

Basic java exception knowledge and some interview questions Java is an object-oriented design language, so exceptions are encapsulated into classes in java, and we only need to know how to handle exceptions, Exception Overview Exception: An exception occurs when the

are characterized by the inability to define variables, and all methods are abstract methods . abstract classes can have variables and do not enforce the need for abstract methods .Inheritance of class 16 and implementation of interfacesParsing: Class Inheriting the parent class implements the interface with the class, which is essentially the same. is to either extend or rewrite the parent class or interface as a template on this template. In practical programming, programmers often need to in

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

Sword refers to Java Implementation of offer programming questions -- interview question 4 replaces spaces, and sword refers to offerImplement a function to replace spaces in a string with "% 20 ". For example, if the string is We Are Happy, the replaced string is We % 20Are % 20 Happy. 1 package Solution; 2 3/** 4 * offoffoffer

Java Architects interview questions, how to become architectsOften interview some candidates, sorted out my interview using the topic, LU continued to organize a lot of problems, so each time to draw a part to ask. The answer will be gradually released in later articles. B

Analysis and Summary of Baidu Java R D interview questions 1. Analysis of Common application scenarios in singleton mode. Among the 23 design modes, the singleton mode is the largest. It is easy to understand, but applicable to scenarios. Are you really familiar with this? The use of Singleton is because there is no need to create an object for each request, wh

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