java 7 interview questions

solves this problem for us. After the online pool submits the callable task, a future object is returned, using which we can know the status of the callable task and get the result of the execution callable returned. The future provides a get () method so that we can wait for callable to end and get its execution results.Read this article to learn more about the callable,future example. 6. What is Futuretask?Futuretask is a fundamental implementation of the future, and we can use it with execut

115 Java Interview Questions and answers-ultimate list (I), 115 java This article will discuss various types of interview questions in Java interviews, which allow employers to test ca

Java interview question Summary 2 (Continuous updates), java questions 1. How to format a date Answer:Date now = new Date (); SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd hh: mm: ss "); String formatNow = sdf. format (now ); The formatNow variable is the formatted date. 2. What are several implementation m

Regular Interview Questions and answers by a ribaba Java engineer, Baba java 1. Implementation of Spring AOP and IOC Http://blog.csdn.net/tarena_lixy/article/details/7096114 Http://blog.csdn.net/kiss_vicente/article/details/6901295 Http://blog.csdn.net/it_man/article/details/4402245 2. Distributed message queue and dis

., GC can avoid memory leaks and stack overflow, effectively improve the efficiency of memory utilization, It also frees programmers from tedious memory management.The string S=new string ("xyz"); How many stringobject are created?2, 1 in the text pool, 1 in the heap, first create 1 "XYZ" objects in the text pool, and then copy an "XYZ" object in the heap and assign it to the reference S.Ninth, Math.Round (11.5) How much? Math.Round (-11.5) how much?Math.Round (x) equals (int) Math.floor (x+o.5f

Let's talk about some questions about the java programmer interview. This blog post is intended for recent graduates and java programmers who have been working for about two or three years. Why do I need to change jobs? This is a broad question. Everyone has an answer. For example: The company is not well-treated, The

The Java Collection framework is the foundation of the Java programming language and is an important knowledge point in the Java interview. Here, I've listed some important questions and answers about the Java collection.In additi

The Java Collection framework is the foundation of the Java programming language and is an important knowledge point in the Java interview. Here, I've listed some important questions and answers about the Java collection.In additi

wrapper type , which means that the wrapper type can be converted directly to the base data type , as shown in the following code:int m=100; Integer im=int N=im; The appeal code directly assigns m to the wrapper object IM, which is automatically boxed and then directly assigns the IM to the basic data type N, which is the automatic unpacking. Although the code on the surface is simple and convenient, however, in essence, the container still uses new to create the object, while unpacking is s

Dark Horse programmer ---- java-based operators, keyboard input, if switch statements, related Interview Questions, ---- javaswitch ------ Java training, Android training, iOS training, and. Net training. We look forward to communicating with you! ------- 1: Operator (master)(1) Arithmetic Operators A: +,-, *,/, %, ++

separately, which belongs to the salvage function operation.Interview question: Please explain the difference between ArrayList and Vector.· These two classes are subclasses of the List interface;· The Vector class is provided at JDK 1.0, and the method of operation provided is synchronous, so it is thread-safeThe Operation class;· The ArrayList class is provided at JDK 1.2, and the method provided is asynchronous, so it belongs to the non-linearProcess-safe Operation classes.If later in develo

Java and C common technical interview questions 2015 (Continuous updates ...), 2015 updating 1. Differences between overwrite and overload Overload is an Overload. It uses the same name as an existing member to declare attributes or methods, but the parameter list is different from that of the original member. Override is mainly used for method rewriting between

Java Collection related interview questions and answers Interview questions1.JavaWhat is a collection frame? What are some of the advantages of a collection framework? There are collections in each programming language, and the original Java version contains several collect

client. The expression is defined between the two tags, 9. What does the implied object mean? What are the hidden objects?JSP implied objects are some Java objects in the page, and the JSP container allows these Java objects to be used by developers. Developers can use them directly without a clear statement. JSP implicit objects are also called predefined variables. The following lists the implied objects

After JDK5, Java provides a more convenient security mechanism that uses lock locks for thread-locked operations and release operations without using synchronized . More clear. Example:Lock lock=new Reentrantlock ();Lock.lockCode that needs to be lockedLock.unlockWhy is lock more secure? Because synchronized may cause deadlock phenomenon, specifically about the deadlock phenomenon can refer to the operating system, there is no more to say.Summarize th

take out 1 position: Product: 4 The consumer takes out from 0 position: Product: 2 producer put in 0 position: Product: 5 consumer removed from 0 Position: Product: 5 producer put in 0 position: Product: 6 consumer is removed from 0 position: Product: 6 producer put in 0 Location: Product: 7 producer puts 1 position: products £ º The producers are placed in the location of the product: 8 Position: Product Consumer removed from 1 position: Product: 9

Java Multithreaded interview questions 1. What is the difference between processes and threads? A process is a stand-alone (self contained) operating environment that can be viewed as a program or an application. A thread is a task that is performed in a process. The Java Runtime environment is a single process that

dispatch and dispatch, and a smaller unit that can run independently than a process. Thread's StrokeThe sub-scale is less than the process, which makes the multi-threaded procedure highly concurrency, and the process typically has independent memory units at execution time, while the threads can share memory. Programming with multithreading often leads to better performance and user experience,But multithreaded programs are unfriendly to other programs because they may consume more CPU resource

First, let's talk about the differences between final, finally, and finalize.　　Second, can anonymous inner class (anonymous internal class) be extends (inherited) other classes, or implements (implemented) interface (Interface )?　　Third, the difference between static nested class and inner class is that the more you say, the better (the more general the interview questions are ).　　Fourth, the difference bet

JAVA engineer interview questionsZookeeper I went to a company for an interview today. I felt dizzy with my brains. I didn't make a few algorithm questions. The questions were relatively simple. I should have prepared myself, but the status was not good, after the