core java interview

Newcachedthreadpool creates multithreading.NewscheduledthreadpoolThis thread pool can specify a fixed number of threads to be executed periodically. For example, by scheduleatfixedrate or Schedulewithfixeddelay to specify the cycle time.PS: In addition to write timed tasks (if not Quartz framework), it is best to use this thread pool to do, because it can ensure that there is always a live thread.Recommended way to use ThreadpoolexecutorIn the case of Ali's

. 245 page71 Video 8.6 Viewer mode for linkage Scenarios 8.4.3 page No. 25172 Video 8.7 Applying a dependency reversal principle can reduce the range of changes affected 8.5.1 No. 254 page73 Video 8.8 A single responsibility principle that can keep classes as stable as possible 8.5.2 No. 256 page74 Video 8.9 The Richter replacement principle to follow when inheriting 8.5.3 No. 257 page75 Video 8.10 Optimizing inherited usage scenarios by using the synthetic Multiplexing Principle page No. 261 of

)Analysis: When a class is loaded, from the parent class to the subclass, from top to bottom, execute the static code block, and then execute the main function , if there is a statement of the new object, The construction code block and constructor of the binding are executed. Note: static code blocks have and execute only once14. What is the result of the following code?public class a{public static void Main (string[] args) {String str;System.out.println ("" + str);}}Analysis: The above code w

block first, and the post constructor)Parse: When a class is loaded and finished, from the parent class to the child class. From top to bottom. Run the static code block first, then run the main function , and if there is a statement for the new object, run the bound construction code block and constructor. Note: static code blocks are available and run only once14. What is the execution result of the following code?public class a{public static void Main (string[] args) {String str;System.out.

chanceWe have met individual candidates, and he knows a little bit about technology, not knowing anything and being available. For example, the project is to Spring MVC, which he only has learning experience, no commercial project experience, but his Java core and database is very good, he just say, Spring MVC does not work, but highlight his strengths, such as an example of his ability to learn, or can en

Java --- Java interview questions (1), java --- java interview questions 1. What is a Java Virtual Machine? Why is Java called a pl

Foreword: The most interview is the SPRINGMVC principle, database optimization, JVM tuning, multithreading Security, reflection, serialization and deserialization. This blog is collected from the Internet. Let's look at how spring works and how things work. Spring Principle One of the core aspects of spring is AOP, which is the aspect-oriented programming that can be used to monitor and control a class o

speaking too much There is nothing substantive to say. In other words, it is useless words. If you cannot explain the problem in a concise manner, the interviewer will doubt whether your performance at work will be as muddy as your conversation? You can first ask the interviewer to determine whether it is necessary to explain in detail. Interpretation is also an art. The key is to determine the focus. If necessary, go deep into the details. When talking about the business, you should look at th

Summary of Java back-end development interview questions of major companies, and java back-end interview questions ThreadLocal (thread variable copy) Synchronized implements Memory sharing. ThreadLocal maintains a local variable for each thread. It uses space for time, which is used for data isolation between threads

system will give a warning or exit The assertion check is usually disabled. Dome: Package com. huawei. interview; public class AssertTest {/*** @ param args */public static void main (String [] args) {// TODO Auto-generated method stubint I = 0; for (I = 0; I 　　 11. Is there any memory leakage in java? Please briefly describe it. Yes. For example: int I, i2; return (i-i2); // when I is a positive number

Win in interview Java multithreading (11), interview java Multithreading121. What is a thread? A thread is the smallest unit that the operating system can schedule operations. It is included in the process and is the actual operating unit of the process. Programmers can program with multiple processors. You can use mul

differences, HashMap and hashtable differences (learn the coding patterns in the underlying JDK for these classes).18, GC is what, why should have GC, simple introduction GC.19, float f=3.4 is correct.20. Introduce the collection framework in Java.21. Implementation of the comparison method in collection framework22. The difference between string and StringBuffer23, final, finally, finalize the difference24. Object-oriented features25, string is the

With regard to the role of Spring MVC's core controller Dispatcherservlet, the following statement is wrong ()?A. It is responsible for handling HTTP requestsB. Loading a configuration fileC. Implementing Business operationsD. Initializing a top-down Application object ApplicationContextWrong choice: AWrong choice reason: Look at the wrong topic meaning, mistakenly think is the right choice.Positive selection: CPositive selection Reason: Spring MVC is

pipeline to achieve this need.[email protected] ~]# Cat File_name.txt | More8. Q: Which user does the data dictionary belong to?A: The data dictionary belongs to the ' sys ' user, and the user ' sys ' and ' Sysem ' are automatically created by default by the system.9. Q: How do I view a summary and usage of a Linux command?Suppose you accidentally see a command in the/bin directory that you've never seen before, how do you know how it works and how it's used?A: Using the command Whatis can show

Java advanced interview question list, java advanced interviewBasic concepts and core design ideas of Object-Oriented Programming This topic explains the polymorphism (polymorphism), encapsulation, cohesion, and coupling ). What is the difference between Inheritance and Aggregation. How do you understand Clean Code

On April 9, October 13, I went to the Huawei core network for an interview with my colleagues. The bird department had been calling us for a long time. However, Huawei's core network seems to be really good. It has been engaged in 3G technology for two years and can be called a "cool man" in the future ....... This is indeed a tragic day, from AM to AM, from

Do you know the 21 core technical points of Java ?, Java 21 core technical points The purpose of this article is to summarize some of my experiences in using java over the years, mainly related to some basic java knowledge points,

Do you know the 21 core technical points of Java ?, Java 21 core technical points The purpose of this article is to summarize some of my experiences in using java over the years, mainly related to some basic java knowledge points,

Summarize the Java Background Development interview questions and the java Background interview questions. Jing er has been summing up some interview questions recently, because he must take everything seriously. The same is true for the

This content is excerpted from the Java Web Lightweight Development Interview tutorialFor qualified programmers, basic database operation skills are required, which are embodied in the following three areas.L First, for a class of databases (such as MySQL, Oracle, SQL Server, etc.), will be basic additions and deletions to the operation, will use some basic functions, will write the stored procedure trigger