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1. Principle of agent mode Wrap the object with a proxy object and replace the original object with the proxy object. Any call to the original object must be called through the proxy object. The proxy object determines whether and when method calls are transferred to the original object. 2. Static proxy mode Here is an example of a clothing ...

brief introduction     1. JSP:          1. Instruction          2. Notes          3. Built in objects      2. MVC development mode      3. EL expression      4. JSTL label      5. Three tier arc ...

Mapping of simple types Returns a simple base type Definition in interface int getAdminCount();//How many pieces of data are returned to the database Specific implementation in xml <select id="getAdminCount" resultType="int"> select count(*) from admin </select> Here I chose a jar package for testing, whi ...

1.1 collection overview When programming, if you want to store multiple data and use the array storage format with fixed length, it may not meet our needs and can not adapt to the changing needs. Then, how to choose at this time—— aggregateCollection features: provide a storage model with variable storage space, and the storage ...

day09 -- object oriented Outline: 1,object-oriented 2,Classes and objects 3,Method overload 4,Construction method 5,this keyword 6,Anonymous object 7,task   Add Qianqian teacher vx to get the latest information     1, Object oriented 1.1 what is object-oriented in life Wash clothes and eat Process oriented: the focus is ...

Detailed configuration and concepts of Spring Spring quick start 1. Import Spring development package coordinates Import coordinates 2. Write Dao interface and implementation class Create Bean 3. Create Spring core configuration file Create applicationContext.xml 4. Configure UserDaoImpl in the Spring core configuration file Confi ...

Introduction to JAVA (4.14) JDK JDK (java development kit) JDK is provided for Java developers, including java development tools and JRE. Therefore, if JDK is installed, JRE does not need to be installed separately JRE JRE (Java runtime environment) Including Java virtual machine (JVM) and core class libraries required by Java programs. I ...

day07 - use of method Outline: 1,Concept of method 2,Method syntax 3,Method use 4,parameter 5,Return value 6,Classification of methods 7,task Add Qianqian teacher vx to get the latest information     1, Concept of method     1.1 what is a method Java Method in, similar to functions in other languages, is a piece of code used ...

1, Annotation 1. Built in annotation 1.1 Override Annotation for overriding superclass methods Can only be used for decorating methods Represents a method declaration intended to override another method in a superclass 1.2 Depecated Not recommended Can be used to decorate methods, properties, and classes Indicates that programmers are ...

monitor Catalog OnlineCountListener.java package com.huangdekai.JavaWeb.listener; import javax.servlet.ServletContext; import javax.servlet.http.HttpSessionEvent; import javax.servlet.http.HttpSessionListener; /** * @Autord: HuangDekai * @Date: 2020/4/28 22:41 * @Version: 1.0 * @since: jdk11 */ public class OnlineCountListener imple ...