core java interview

Multithreading and concurrency issues are among the questions that interviewers prefer to ask in a Java technology interview. Here, the most important questions are listed from the interview point of view, but you should still have a solid grasp of the basics of Java multithreading to match the problems you encounter l

1. The relationship between JDK,JRE,JVMJVMIs the Java virtual machine, is the Java important guarantee of cross-platform, JVM realize the Java premise of cross-platform, can be different for different operating system JVM .Languages can be said to Java be cross-platform, but JVM not.JREIs the

primitive types in generics. The 2nd difference between them is that you can pass any type with a parameter to the original type List, but you cannot pass list144, write a generic program to implement the LRU cache?This is the equivalent of an exercise for people who like Java programming. To give you a hint, linkedhashmap can be used to implement a fixed-size LRU cache, which moves the oldest key-value pairs out of the cache when the LRU cache is fu

I was also reading the interview book while learning the video. The record is as follows: 1. LostAfter learning the 2010java high-tech video from Teacher Zhang Xiaoxiang for so many days, he looked at generics, reflection and other things and turned his mind away. He just learned that none of the Main Lines dragged me. That is to say, I am eager to know what major technologies will be required for future development and what is the

execution path; the so-called execution path refers to the directory list where the operating system searches for a local executable file.The same level directory in Jdk\bin contains the Src.zip file, which is the source code for all public classesGet more source code (compilers, virtual machines, local methods, and private helper classes, etc.) with access to: Oracle.net.Here is the anatomy of the JDK section:The difference between the JDK and the JRE can be seen clearly:There are three types

the interviewer came, first gave a piece of paper let me do the question and then left, I look at a face, 15min did not write; After the interviewer came back to ask me what the situation, I said I am not familiar with Java, he said this is not Java, very embarrassing. He asked me to write a binary tree follow-up traversal non-recursive, but also a face, tossing a half-day even a train of thought also, did

I. Working principles and concepts of spring's core (IOC and DI,AOP).1.IOC Control InversionConcept: Control is shifted from the object itself to the container; The container creates an instance from the configuration file and creates a dependency between the individual instancesCore: Bean factory; In spring, the individual instances created by the Bean factory are called beans.2.Di Dependency InjectionIn fact, Di and IOC are the same concept, because

(decorative mode), Flyweight (enjoy meta mode), proxy (proxy mode),Command (order mode), interpreter (interpreter mode), Visitor (visitor mode),Iterator (iterative sub-mode), Mediator (mediator mode), Memento (Memo mode),Observer (Viewer mode), State (status mode), strategy (policy mode),Template method (pattern mode), Chain of responsibleity (responsibility chain mode)Factory mode: Factory mode is a frequently used pattern, and classes implemented according to the factory pattern can generate

First, to talk about final, finally, finalize the difference. Most often asked.Second, Anonymous Inner class (anonymous inner Class) can extends (inherit) other classes, can implements (implement) interface (interface)?Thirdly, the Static Nested class and the Inner class are different, the more said the better (some of the questions are very general).The difference between, and . This is a very small question.The difference between HashMap and Hashtable. Frequently asked.The difference between t

Java memory allocation and management is one of the core technologies of java, today we go deep into the Java core, in detail about the Java in memory allocation Knowledge. In general, Java