Java

1 Packagecom.jdk7.chapter4;2 3 Importjava.util.ArrayList;4 Importjava.util.LinkedList;5 Importjava.util.List;6 ImportJava.util.ListIterator;7 ImportJava.util.Stack;8 ImportJava.util.Vector;9 /**Ten * List of forms of collections in Java (sequential

Brief introductionException handling is one of the most important features of the Java language, as explained in the article "Three rules for effective Exception handling": It mainly helps us to solve the following three problems in the debug

?? Volatile is a familiar keyword in Java concurrency programming. Even if you have never used it, you will occasionally see it in technical books or blogs. The explanation of the volatile keyword is often taken over: the modified variable has

In some cases, some code needs to be executed when the project is started, and a static block of code is required, and this code is executed proactively.Static code blocks in Java are executed when the virtual machine loads the class, and only once.

ThreadsMultithreading is a program in which multiple threads are executing concurrently.How the CPU works under multi-threadingIn fact, theCPU ( central processing Unit ) uses preemptive scheduling mode to switch between multiple threads at high

Copyright NOTICE: This article for Bo Master original article, without Bo Master permission not reproduced. http://blog.csdn.net/chenchaofuck1/article/details/51045134Java when writing multi-thread program, in order to ensure thread security, need

JavaIn2Methods of handling exceptions：1and direct treatment in the place where the abnormal is made;2, throw an exception to the caller, and let the tune-up handle.Exception classification1, Check for exceptions:Java.lang.Exception2, Operation

Java provides the API class BigDecimal in the Java.math package to perform precise operations on the number of more than 16 significant bits. Double-precision floating-point variable double can handle 16-bit valid numbers, but in practical

I. What is an exceptionAbnormal English words are exception, literal translation is the meaning of "accident, exception", that is, abnormal situation. In fact, exceptions are procedural errors in nature, including procedural logic errors and system

I. Overview　Using the Java language to develop applications, under the Windows platform, there are generally 3 types of applications:　　 1. Web Apps . Most web Apps run as war packages in web containers, such as Tomcat,jetty.　　2. Desktop apps.

The immutable class is the name of the class that cannot be re-assigned after it is instantiated, and the eight wrapper classes and java.lang.String provided by Java are immutable classes.Rules to be followed for creating custom immutable classes:1.

Problem Description: began to install the jdk8 later installed Jdk9, can be configured for the project different JDK, peaceful; Today found that the software needs JDK8 environment, the results of my java-version is always jdk9.0.1;

public class Employeedemo {//Method one: public int search (string str,string strres) {//lookup string in the same number as the specified string int n=0;//counter//for (int i = 0;i　　The same number in the Java lookup string as the specified string

Introduction of today's content1. Creation and use of reference type variables2. Selection statement of Process Control statement3. Loop statement of Flow control statement4, Cycle advanced01 Creating a reference type variable formula* A: 创建引用类型变量公式

Android enumeration advantages and disadvantages and alternative solutions Enumeration should not be used on Android, which occupies memory. Replace it with the @ XXXDef annotation.Disadvantages of using Enum Each enumerated value is an object,

Springboot uses a listener to collect statistics on the number of online users. Case study: springboot listeners In the springboot project, this article uses the HttpSessionListener listener (one of the listeners) to count the number of online users.

Spring Boot war package instance tutorial, springwar In addition to executable jar packages, Spring Boot also supports traditional war packages. This article describes how to use Spring Boot to build a traditional war package. Follow these steps to

In Java, one method is used to call another method. In java, another method is called. In the same class: For static methods, other static or non-static methods can be called directly. For non-static methods, other non-static methods can be called

JAVA novice cool-test extracts substrings composed of the same characters, java cool-test Given a string and a substring feature tag, you must extract all the substrings represented by the feature tag from the source string, such: Given source

Servlet and related classes and interfaces The previous article introduced Web in the web project. the configuration information of the xml file. This article mainly introduces the very important configuration-Servlet configuration, focuses on