Java

File Filedirs = new file ("path"), if (!filedirs.exists ()) filedirs.mkdirs (); File File = new file ("path", "filename"), if (!file.exists ()) {file.createnewfile ();/** * Create xls file *///string createFile = Reportco Nfig. bulletinreport+ "\ \"

JSP-14-common collection classes and interfaces, jsp-14-set InterfacesList Interface The List interface and implementation class are variable-capacity lists. They can access elements in a set by index and are ordered sets. Arraylist is an

Spring (3.2.3), spring3.2.3BeanFactory & ApplicationContext Org. springframework. beans. factory. BeanFactory is the most basic Spring container interface, which provides some basic functions for Bean management. The BeanFactory Interface contains

Spring (3.2.3), spring3.2.3 Dependency InjectionIt means that when another object is required for collaboration (accessing its properties or calling its methods) during the program running, you do not need to create the called user in the code, it

Spring (3.2.3), spring3.2.3P namespace The p namespace allows you to use the attributes of the bean element instead of the sub-element to describe the attribute values of the Bean instance. Starting from Spring2.0, Spring supports simplified

Spring (3.2.3), spring3.2.3 If the Bean property is a set, you can use the , , , and elements to inject values to Properties of the List, Set, Map, and Properties types.   Configuration example for injecting set values:

Spring (3.2.3), spring3.2.3 By default, after the Spring IoC container is started, all instances of beans defined by singleton are created and configured in singleton mode during initialization. Generally, it is advisable to instantiate the Bean in

Java variable parameters Java adds new features:Variable parameters: when the number of parameters is uncertain and the type is determined, java treats variable parameters as arrays.Note: The variable parameter must be in the last one. When there

Maven dependency Summary: maven dependency I. Scope of dependency Maven uses a set of classpath when compiling the main code of the project. Second, another classpath is used during compilation and execution of the test. Finally, a set of classpath

Spring (3.2.3), spring3.2.3 Spring containers can manage the lifecycle of beans in the singleton scope. containers can track the creation and destruction of Bean instances. There are two main opportunities to manage Bean lifecycle behaviors:After

Java basic notes-abstraction, inheritance, polymorphism, java Polymorphism Abstract class: abstract Modification Abstract methods must be defined in abstract classes. abstract classes cannot create objects. Abstract methods do not define abstract

Java Memory Allocation Policy1. objects are preferentially allocated in Eden. In most cases, objects are allocated in the new generation of Eden. When the Eden area does not have enough space, the virtual machine will initiate a Minor GC. In the

Singleton Design Mode23. Singleton Pattern) Concept:Java Singleton mode is a common design mode. Singleton mode is divided into three types: lazy Singleton, ELE. Me Singleton, and registered Singleton.The Singleton mode has the following features:1.

Reclaim the ImageView after bitmap and the callback method before the activity is killed 1. Reclaim the ImageView after bitmap 1.11 ImageView imageView1 = (ImageView) findViewById (R. id. imageView1 );Bitmap = BitmapFactory. decodeResource

Design Mode-Metadata Mode The original Article "Use share to support large number of fine-grained objects efficiently" indicates that using shared objects can effectively support a large number of fine-grained objects. Here, shared objects refer to

@ Override error during Java project splitting Today, a new project is created to split dependencies of all projects. Therefore, the previous code is used, so a lot of errors are reported, @ Override. Check and find that JDK selection is a problem.

Breakthrough in cross-origin access restrictions of ajax Ajax cross-origin access encounters this exception: XMLHttpRequest cannot load http: // 10.43.15.23/hnsh/rest/waterInfo/getRiverInfo. do. no 'access-Control-Allow-origin' header is present on

Hdu 2015 even sum (java) Problem: I personally think it is better to refer to other people's Weibo methods for segment computing. We found another convenient method for processing the ending number without spaces.   Even sum Time Limit: 2000/1000 MS

Several important parameters for nginx high-performance java web Applications On the Internet, nginx has many high-concurrency configurations, mainly nginx + php. This article describes how to configure nginx java web applications to achieve high

Java decoration mode (Decorator Mode)Decorator is often translated into "decoration". I think decorator is used to paint a painter, so the object to be painted is called decoratee. These two entities are required in the Decorator mode.Decorator