I learned Spring today and suddenly wanted to review the Java class loading and class reflection. Consolidate the underlying principles. Some of them refer to Teacher Li Gang's crazy Java handout and Spring3.x enterprise application development practices by Chen xionghua and Lin kaixiong. 1. A command corresponds to a
Dark Horse programmer _ Java exception common Java Library Class, dark horse _ javaJava exception 1: Basic concepts of exceptions
Exceptions are a type of command flow that causes program interruption. They are abnormal during runtime. in Java, all exceptions follow the object-oriented design philosophy, all exceptions
A. class file
Note: Each class file corresponds to a unique class or interface definition information, but the class or interface is not necessarily defined in a file (for example, a class or interface can also be generated directly from the ClassLoader).
Secon
Class Loader?? The virtual machine design team takes the "fully qualified name of a class to obtain a description of this type of binary byte stream" in the class loading phase, which is implemented outside the Java Virtual machine. So that the application can decide for itself how to get the classes it needs. The code
The de jure command corresponds to a process.
When we start a Java program that starts a main method, it starts a Java virtual machine process, no matter how complex the process is. Different JVM processes do not interact with each other. This is why the Java program has only one entry--main method that allows the virtual machine to invoke. The two Mian methods,
Encapsulation: is to encapsulate some attributes and methods into a class.
Inheritance: Just as subclasses inherit some of the properties and methods of the parent class.
Polymorphism: Just as a parent class has several distinct subclasses.
Here I do not explain more, the following I mainly explain an inheritance. Inheritance is a feature of OOP (object-oriented)
Preface:Java's library is growing and contains countless classes and interfaces. But there are some very important classes and interfaces, which are the core part of the Java class library. Common examples include string, object, class, collection, classloader.... Familiarizing yourself with these classes is the basis for learning
Java Study Notes 6 -- class inheritance, Object class, and study notes 6 --
Next, we learned the following:
Java study notes 5-Class Method
Java Study Notes 4-basic concepts of classes and objects (2)
Class, abstract class, interface, inheritance and object (Java)
Zookeeper --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------This is not a teaching material. I sometimes look at it on th
In the previous blog we mentioned ClassLoader, knowing that ClassLoader was used to dynamically load a class file into memory, but how did this class file be generated? Where did it come from? This in turn involves another conceptual-java.lang.class.Class is a special class for Java, which is an abstract
This article mainly introduces the Java language class class usage and generalization (detailed), we all know that Java program in the running process, all the object type identification, that is, Rtti. This information records the class to which each object belongs. A virtu
. Some design and programming problems * are difficult to solve without the ability of an inner class to inherit multiple concrete or abstract classes. From this point of view, the inner class makes the solution of multiple inheritance complete. The interface solves some of the problems, while the inner classes effectively * implement multiple inheritance. "Java
Many people may not be familiar with the inner class mentioned in Java. In fact, similar concepts also exist in C ++, that is, nested class (nestedClass). The differences and relationships between the two are compared in the following section. On the surface, an internal class defines another
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The version number of the magic number and
strings, dates, and numbers are the most commonly used data objects in Java programs, and the creation, modification, formatting, and transformation of these data are incorporated into every corner of the Java program and must be mastered. This section demonstrates the following common entity classes through an instance
Java System-Level classes: System
.joingame (); System.out.println ("Total =" +child.total); }}//Define Child Classesclasschild{intAge ; String name; //Total is a static variable, so it can be accessed by any object Static intTotal=0; PublicChild (intage,string name) { This. age=Age ; This. name=name; } Public voidJoingame () { total++; System.out.println ("One of the children has joined."); }}2. What is a class method and why is there a
Java object-oriented -- class loaders and reflection, java object-oriented -- LoadingThe relationship between jvm and class in the Class Loader
When you call a java command to run a java
StaticClassStatic class (Java)
In general, the class cannot be modified using static. If you must use the static modifier class, the static modifier is usually an anonymous internal class.
Create another class in a
Objective
This article describes the pattern classes and Matcher classes in Java regular expressions. First we need to be clear that the regular expression specified as a string must first be compiled into an instance of the pattern class. So how to better understand these two classes, is what programmers must know.
Let's take a look at these two classes separately:
First, the concept of capturing groups
By building a class loading component container framework that can isolate Java class loads into a specified jar file, you can ensure that runtime loads the component version you expect.
Java's class loading framework is powerful and flexible. It allows applications to access clas
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