table of Contents
Early bird gets the worm.
2019 classic java interview 100 asked, enter BAT is not a dream.
2019 coming to an end, After receiving end awards are not the quit of it, ready to get up early, small partners.
This article compiled by the public number "Love IT", designed by the java-based content to the database, SSM framework, redis, message queues, spring boot, spring cloud, git and a number of front-end knowledge.
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A, java foundation
1, object-oriented features have what? [Base]
2, int and Integer What is the difference? [Base]
3, Math.round (11.5) equal to the number? Math.round (-11.5) equals how much? [Base]
4, the programming problem: 2 multiplied by calculating the most efficient way equal to a few [8] basis?
5, the array has no length () method? String has no length () method? 【basis】
6, the constructor (constructor) can be rewritten if (override)? 【basis】
7, can inherit String class? [Base]
8, when an object is passed as a parameter to a method, this method can change the properties of this object, and returns the result of changes in the value of this in the end is passed by reference or pass? [Base]
9, String and StringBuffer difference? [Base]
10 difference, String, StringBuffer StringBuilder is. 【basis】
11, the difference between overloading (Overload) and rewritable (Override) is. Overloaded method can be differentiated according to the type of return? 【basis】
12, describe the principle mechanism JVM class document loading? 【medium】
13, interface implementations can do? 【medium】
14, if you can make calls to non-static method from within a static method? 【basis】
15, GC is the What? Why should there be GC? [Base]
16. What is the basic principle is that the garbage collector? The garbage collector can immediately reclaim memory? Is there any way the initiative to inform the virtual machine garbage collection? 【basis】
17, a ".java" if the source file can contain multiple class (not an internal class)? What are the limits? 【basis】
18, Java's final keyword in what usage? 【basis】
19, encoding conversion: how to GB2312 encoded string into ISO-8859-1 encoded string? 【basis】
20, error and exception What is the difference? [Base]
21, try {} there is a return statement, then the code immediately after this finally try {} Lane will not be executed, when executed, the return before or after? [Base]
22, List, Set, Map whether inherited from the Collection interface? 【basis】
23, say ArrayList, Vector, LinkedList storage performance and characteristics? 【basis】
24, HashMap and Hashtable difference? [Base]
25, Arraylist and Vector difference? 【basis】
26, List, Map, Set three interfaces, accessing elements, what are the differences? 【basis】
27, sleep () and wait () What is the difference? [Base]
28, when a thread enters a synchronized method of an object, other threads can access this object other methods? [Base]
29, there are several multi-threaded implementation, are what? There are several synchronous implementation, are what? [Base]
30, when a thread enters a synchronized method A object, other threads can access synchronized method B of this object? 【medium】
31, outlining the similarities and differences between synchronized and java.util.concurrent.locks.Lock? 【medium】
32, writing multithreaded programs There are several ways to achieve? 【medium】
33, Java how to implement serialization, what is the point? 【medium】
Second, the database
34, set forth steps JDBC database operation. 【basis】
35, when the operation of the database using JDBC, how to improve the performance of data read? How to improve the performance of update data? 【medium】
36, during the programming database connection pool What is the role? 【basis】
37, ACID affairs What does it mean? 【basis】
38, talk about dirty reads, phantom reads and non-repeatable read? 【medium】
39, JDBC how to carry out a transaction? 【medium】
40, get a class object of the class what way? 【basis】
41, JSP which have built-in objects? What role are? 【basis】
42, get and post requests difference? 【basis】
43, to explain the four JSP scopes. 【basis】
Three, SSM framework
44, MyBatis What is the difference in use # and $ write placeholder? 【medium】
45, explain the role MyBatis namespace (namespace) of. 【medium】
46, what is the IoC and DI? DI is how to achieve? 【medium】
47, explain what AOP (Aspect Oriented Programming)? 【basis】
48. How do you understand the "cross-cutting concerns," the concept? 【medium】
49. How do you understand the connection point (Joinpoint) AOP in the cut point (Pointcut), enhanced (Advice), introducing (Introduction), weaving (Weaving), section (Aspect) these concepts? 【basis】
50, Spring's transaction management support What types? Which way you use in your project? 【medium】
51, Spring MVC works is like? 【basis】
52, What is XSS attack? 【difficult】
53, SQL injection attacks? 【difficult】
54. What is CSRF attack? 【difficult】
Four, redis
55, which has the benefits of using redis? 【basis】
56, Redis what data structure? 【basis】
57, if a large number of key needs to be set at the same time has expired, the general needs attention? 【medium】
58, why Redis need to put all the data into memory? 【medium】
59, Redis provides what kinds of persistent way? 【medium】
60, how to choose the right way of persistence? 【medium】
61, redis support java client which you used? 【basis】
62, the main Redis cluster replication model from what? 【difficult】
63, between Redis cluster is how to copy? 【medium】
64, how to test the connectivity of Redis? 【basis】
Fifth, the message queue
65, why should the message queue? [Medium]
66, the use of message queues Are there any disadvantages [medium]
67, Why use RocketMQ; difference RocketMQ and ActiveMQ the [difficult]
68, RocketMQ is how to ensure high availability of the system? 【difficult】
69, messaging middleware cluster crashes, how to ensure that one million production data is not lost? 【medium】
六、spring boot
70, Spring Boot core configuration files and which of? What is the difference between them? 【medium】
71, Spring Boot configuration file, which has several formats? What's the difference? 【medium】
72, the core notes Spring Boot Which? It mainly consists of several notes which composed? 【basis】
73, open Spring Boot characteristics, which has several ways? 【basis】
74, Spring Boot requires a separate container to run it? 【basis】
75, how to run some specific code when Spring Boot start? 【medium】
76, Spring Boot There are several ways to read the configuration of what? 【medium】
77, Spring Boot how to define different sets of environment configuration? 【medium】
78, SpringBoot timing task how to achieve? 【medium】
79, how we connect a like MYSQL or orcale same external database? 【medium】
七、spring cloud
80, what is the micro-service [medium]
81, between micro-communication service is how independent Dubbo spring Cloud and what difference there? [Difficult]
82, springcloud how to achieve registration and discovery services [medium]
The difference between 83, Ribbon and Feign of [medium]
84, the role of springcloud breaker [medium]
85, springcloud how to achieve registration and discovery services [medium]
86, springcloud the components are those? 【medium】
Eight other
87, the difference between the cookie and session [base]
88, a complete http request process [medium]
89, to talk about long connection [difficult]
90, TCP how to ensure reliable transmission? 【difficult】
91, the difference [medium] URI and URL's
92, the difference between http and https? 【medium】
93, docker commonly used commands [medium]
94, what is the Docker mirror? 【medium】
95, what is the Docker containers? 【medium】
96, what is the Docker Hub? 【medium】
97, what is Git engraved (fork)? Engraved (fork), What is the difference between a branch (branch) and clone (clone)? 【medium】
98. What is the difference between "git pull" and "git fetch"? 【medium】
99, using Ajax What are the advantages and disadvantages? 【medium】
100, cross-domain issues, who cross-domain restrictions, how to solve [the difficulties]
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