Java

Build Struts2 is the focus, build this framework some trouble, encountered a lot of problems, finally one by one settlement, written here, to make memo.1. First to download some components of struts2, the version I downloaded is

1, the use of official regular jarCommons-net-1.4.1.jarJakarta-oro-2.0.8.jarNote: Downloading files from Windows Server using FTP is not the same as downloading files from a Linux server2. download files from Linux server with FTPSystem.out.println (

Java5 before, as in the following two kinds:The first type:New Thread () {}.start (); This means that the run method of the thread subclass object is called , and new Thread () {} represents an instance object of an anonymous subclass of thread,

Recently been OutOfMemory error, record a little bit of Setup JVM virtual machine memory Java heap space method.Tomcat 7 Reference: http://www.davidghedini.com/pg/entry/install_tomcat_7_on_centoshttp://blog.csdn.net/f_zongjian/ article/details/572366

Print Flowbyte stream Print stream PrintStreamCharacter Print stream PrintWriterCharacteristics of the print stream:A: Only the data is written, no data is read. Only the destination can be manipulated and the data source cannot be manipulated.

As a program ape, we write code every day, but do you really know the life cycle of it? Let's talk about its life course today, say a Java Code, from birth to game over a few steps: Compile, class load, run, GC.CompileThe compilation period of the

First, to modify the remote host (Linux) related files to be accessed, this document only describes the JMX mode of JAVA-JVISUALVM:1. Open $catalina_home/bin/startup.sh and find the penultimate line (that is, exec "$PRGDIR"/"$EXECUTABLE" start

In the actual development and application of Java projects, it is often necessary to use the basic function of converting objects to string. This article will make a summary of the common conversion methods. Common methods are object.tostring (),

(Transferred from: http://www.cnblogs.com/dolphin0520/p/3780005.html)Automatic boxing and unpacking is a commonplace problem in Java, so let's take a look at some of the problems in boxing and unpacking today. This article first tells about boxing

1 1. Collection 2 　　 Collection (Single-column collection)3 　　　　 List (ordered, repeatable)4ArrayList5 The underlying data structure is an array, query fast, and delete slowly6 thread insecure, high efficiency7 　　　　　　 Vector8 The underlying data

1 PackageZl_file;2 3 ImportJava.io.File;4 Importjava.io.IOException;5 ImportJava.text.SimpleDateFormat;6 Importjava.util.Date;7 8 /*9 　　　 Judging function :Ten Public Boolean isdirectory (): Determines whether it is a directory (folder) One

Java Virtual Machine Specification Although there is no mandatory constraint at when to start the class loading process, but for the initialization of the class, the virtual machine specification is strictly defined to have and only four cases must

Directly write the code of the class and the package itself import create, hand hit very tiredpublic static void Main (String args[]) {FileReader Fr=null; File input streamFileWriter Fw=null; File output streamBufferedReader Br=null; Character

HTTP Communication overviewThere are two main ways in which HTTP communication is post and get. The former through the HTTP message entity sends the data to the server, the security is high, the data transmission size is not limited, the latter

Definition classes: Access Modifiers class class name {}  access modifier such as: Public, priate is optional class is the keyword that declares the class according to the naming convention, class name capitalization   Example: Create "People" class,

Write a Objecttool classGeneric method: Defines a generic type on a methodFormat public return type method name (generic type)The benefits are:This generic method can receive any type of data1 Public class Objecttool {2publicvoid show (T t)

Java code:public static void main (string[] Args){Object obj1 = new Object ();Object obj2= New Object ();Object obj3 = obj2;System.out.println ("obj1==obj2?") +obj1.equals (obj2));System.out.println ("obj2==obj3?") +obj2.equals

GitHub Address: objects and classes in Https://github.com/lily1010/java_learn/tree/master/dogjavaAll things in Java are objects, such as animals, cats, dogs, fish and so on, they can run, can breathe, in short, they have some common characteristics

Java thread fair lock ReentrantLock (boolean fair), reentrantlock fair lockI. Fair lock 1. Why is there a fair lock? The CPU selects a thread randomly while waiting for the queue to schedule the thread. Because of this randomness, the thread cannot

Server Tomcat v7.0 Server at localhost failed to start. One of the possible causes of the error is tomcatlocalhost.Story: Learning Servlet, suddenly found this problem when starting Tomcat Synopsis: When learning servlet, you can't even get started