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
oracle| problem
ORACLE interview Questions-Technical articles (2)
21. How to determine the time zone of the database?
Answer: SELECT dbtimezone from DUAL;
22. Explain the purpose of global_names set to True
Answer: Global_names indicates how the database is joined. If this argument is set to True,
You must connect th
Oracle interview questions: complex queries and instance analysis
When you need to perform complex processing on the queried results, you can obtain the expected results by means of joint queries and subqueries. The following is a typical question, which is intended to inspire readers.1. Question requirements:
Table NBA records TEAM
Name and year of the winning
.
}
}
56. Problem: Give an integer variable A, write two pieces of code, the first set of a bit3 is 1, the other bit does not change, how to implement it?
/**
* @author sanchan
* @since 1.0
*/
publicclassTest{
publicstaticvoidmain(String[]args){
//给一整型变量a,写两段代码,第一个设置a的bit3 为1,其他bit不变,怎么实现呢?
inta=8;
//打印二进制
System.out.println(Integer.toBinaryString(a));//输出 1000
System.out.println(Integer.toBinaryString(a|4));//输出 1100
}
Links: http://ifeve.com/java-multi-threading-concurrency-interview-questions-with-answers/Original: Http://www.journaldev.com/1162/java-multi-threading-concurrency-interview-questions-with-answersMultithreading and concurrency iss
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
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 consumer removed from 0 positions: Products:
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
115 Java Interview Questions and answers-ultimate list (I), 115 java
Object-Oriented Programming (OOP)
Java is a computer programming language that supports concurrency, class-based, and object-oriented. The advantages of object-oriented software development are listed bel
Original link: http://ifeve.com/java-multi-threading-concurrency-interview-questions-with-answers/Multithreading and concurrency issues are among the questions that interviewers prefer to ask in a Java technology interview. Here,
Java interview 30 Question 1: What are 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 inter
Oracle interview questions
1. Simple SQL query:
1): count the number of employees in each department
Select Dept, count (*) from employee group by dept;
2): count the number of employees in each Department greater than one record
Select Dept, count (*) from employee group by dept having count (*)> 1;
3): the name of the department where the employee whose salary
This article originates from: http://www.dbasupport.com
The answer here is not very comprehensive, these questions can be explained through a number of angles, perhaps you do not have to give a full answer in the interview process, only through your answers to the interviewer to understand your understanding of the Oracle concept.
1. Explain the different points
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
; k ) TestFunction (k, J, i);On the basis of scenario one, this scheme puts the instantiation of the cyclic variables out of the loop, which can further reduce the number of instances of the related cyclic variables, and the scheme time-consuming situation is as follows:
Variable
Instantiation (number of times)
Initialization (number of times)
Comparison (number of times)
Self-increment (number of times)
I
1
1
10
1
Java custom generic interview questions: receive any array to reverse, java custom
You can only operate on a certain type for reversal without using the generic type.
The Code is as follows:
package com.swift.fanxing;import org.junit.Test;public class RenyiReverse { @Test public void test() { int arr[]=new
create threads, how to create threads better (such as inheriting the thread class or calling the Runnable interface), and then gradually ask about concurrency problems like the Java memory model encountered in the process of Java concurrent programming, JDK1.5 introduces higher-order concurrency tools, common design patterns for concurrent programming, classic multithreading issues such as producer consume
Collections.sychronizedlist to decorate a collection.In fact, vectors combine a set of "mutable arrays" and synchronize the implementation of each operation. This is another design flaw. Vector also has some legacy methods in enumerations and elements to get methods that are different from the list interface, if these methods in the code programmers tend to want to use it. Although enumerations are faster, they cannot be checked if the collection is modified during iteration, which can cause pr
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
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.