Java

In Java, three reference classes are defined in the Java.lang.ref package, namely soft, weak, and virtual references. These 3 classes provide a convenient mechanism for interacting with garbage collection mechanisms and providing a mechanism for

This Java green installation configuration, as well as never own the use of the computer to speak up.Recently, the computer is running slowly, a long time did not clean up and maintenance, and there may be poisoning or trojan, so the system has been

Method One: Implement the comparable interface Packagecom.java.test; Public classPersonImplementsComparable { PrivateString name; PrivateInteger age; PublicPerson () {} PublicPerson (String name, Integer age) { This. Name =name; This. Age =Age ;

A long time ago to listen to a great God lectures, during the mention of iterator, do not look at its simple method, but assembled like "Data processing plant" the same!The following is a brief introduction to the first three main methods of

1. Simple Factory mode1.1 OverviewAlso called the static Factory method pattern, which defines a specific factory class that is responsible for creating instances of some classes. 1.2 AdvantagesClients do not need to be responsible for the creation

Java translates the source code (sourcecode) into bytecode (bytecode): Javac Myclass.java, and then executes bytecode on the Java Virtual Machine (JVM): Java MyClass. Java is based on object-oriented Programming (OOP), and the three principles of

Transferred from: http://txy821.iteye.com/blog/760957Java.lang.String's Intern () methodThe return value of the "ABC". Intern () method is also the string "abc", which looks as if this method is of little use. But in fact, it made a little

Recently watching video, see more classic than the size of the problem. Enter two numbers, return a large number, type can be int,long,float, etc.The general tutorial uses this example to introduce the concept of constructors and overloading, and

Enum methods in Java ToString and ordinal methods Public enumLanguage {C, Java, PHP;} Public classEnumdemo { Public Static voidMain (String args[]) {//returns the name of this enum constant (String)SYSTEM.OUT.PRINTLN ("Programming in"

Java Web developers know that they often worry about missing a variety of jar packages and often go to various places to download them. It's easy to use MAVEN to manage your project's jar packages, and MAVEN will automatically help you download the

There are generally two random numbers in Java, one is the random () method in math, and the other is the random class.First, Math.random ()The decimal number of the 0Example: How to write, generate randomly generate one of the 0~100 in the

Java Learning Note 16--exceptionAbnormalAn exception that causes the program to run a flow of instructions, if the exception is not properly handled, it can cause the program to break execution, causing unnecessary loss,Therefore, in the design of

Purpose of writingSelf-taught Java, the concept ofJava Stream is more complex, so specifically for a collation. Expected to start learning children's shoes, after reading this article on the Java Stream has a general understanding. Mainly divided

The 17th Chapter Network programming17.4 Network programming based on UDP protocolUDP protocol is an unreliable network protocol, it establishes a socket on both ends of the communication instance, but there is no virtual link between the two

I. SUMMARY of rulesThe lightweight synchronization mechanism, variable v is the volatile type.(1) In working memory, the most recent value is flushed from main memory before each use of V to ensure that the modified values of the variable v are

Poi export excel and poiexcel I. Introduction HSSF is the implementation of POI project's pure Java Excel97 (-2007) file format. XSSF is a Java implementation of the POI project Excel 2007 OOXML (.xlsx) file format. HSSF and XSSF provides multiple

Shared variables for java multi-thread Communication(1) when accessing the Common Code: You can use the same Runnable object, which contains the shared data, such as the ticket selling system. Or the shared data is encapsulated in an object, and the

Difference between Java heap and stack Variables of some basic types defined in the function and referenced variables of the object are allocated in the function stack memory.   When a variable is defined in a code block, Java allocates memory space

Passing Java parameters by value? Pass by reference Sometimes I want to know whether to pass by value or by reference when calling a method. Some people say that the basic data type is passed by value, and the reference type is passed by reference.

Java core technology: an in-depth understanding of abstract classes and interfaces1. General description Abstract classTemplate Method ModeInterface2 abstract class Abstract classes are classes that cannot be instantiated. They are generally