Unification recently wanted to find a summer internship. After Haitou, he received an invitation for a written test from Endpoint Technology. When he opened it, it was a spring call. . . It feels cold~~~
A total of 37 questions, two programming questions, and the rest are all single-choice and multiple-choice questions. Most of the multiple-choice questions are Java grammar, and a few are computer networks and operating systems.
The first string algorithm question: Given a string word array String[] words = ["abcd","dbac","abc","cba","bca"], find out that the characters are the same but the order is different The words are output in a new line.
Such as:
["abcd","dbac"],
["abc","cba",bca"]
The second handwriting implements a thread-safe singleton pattern class.
Multiple-choice part:
1. The TCP three-way handshake Time-Wait may/must happen at which stage of the client/server
2. The practical application of ==.equals
3. Several multiple-choice questions of abstract class abstract have been tested, including whether it can be inherited and whether abstract methods can be implemented.
4. Can the interface method be modified by private?
5. In the thread pool and the difference between submit() and execute(), can you inherit the collable interface?
6. Which JVM garbage collection algorithm is not available?
7. Give a piece of code, whether it compiles incorrectly, runs normally, or chooses the correct result
8. Generics: <String T alibaba> String nums, T {return numbers;} (I saw this kind of thing for the first time, probably this, don’t remember) Determine which position is wrong A, the first String B , Alibaba C, the second String D: normal
9. Ask what is the final output list.get(1).
public Test{
public void addList(ArrayList list){
list.add(1);
list=new ArrayList<>();
list.add(3);
list.add(4);
}
public static void main[]{
List list=new ArrayList<>();
list.add(0);
addList(list);
}
}10. The school allocates 1024 hosts and asks what the IP address subnet mask is.
11. Select which sorting algorithm time complexity is O(n^2). A, bubbling B, insert C, fast row
12. Can the final keyword modify the abstract method?
13, in Linux select、expoll用法
14. Can Mysql index column be empty
15. Process and thread space allocation issues. The C option process is the basic unit of resource allocation. I remember this option, hahaha.
I can't remember the rest 