Java learning - exceptions (concept, classification, exception handling mechanism, (try, catch, finally), throw and throws, custom exceptions)

1. Concept of exception (1) What is an exception The so-called exception refers to some abnormal things that occur during the operation of the program (for example, except 0 overflow, the array subscript is out of bounds, and the file to be read does not exist) (2) Consequences caused by abnormality If an exception event occurs during the e ...

Posted by marcela1637 on Sun, 19 Dec 2021 22:18:56 +0100

JavaWeb - file upload and download - power node learning notes of Eclipse version

JavaWeb - file upload and download BiliBili frog course network [power node] JavaWeb eclipse learning video website The article is only for sharing learning experience and reviewing. It is more effective to check the formal video website and official documents analysisascriptionremarksmutipart/form-dataMultipart request / form dataFile upload ...

Posted by pseudonym on Sat, 18 Dec 2021 03:53:21 +0100

Java exercise - 08

1. Requirement Description: implementation idea of encapsulating member variables of webworm package, Superman package and chat package: 1 Add an access modifier to the attribute; 2. Create setter s and getter s. import java.util.Scanner; //Internet worm package public class WangChong { private String name; private int price; private int ti ...

Posted by cupboy on Fri, 17 Dec 2021 02:40:54 +0100

Keywords final, static

Keyword final The meaning is final and invariable final attribute and temporary variable cannot be modified once assigned Attribute assignment can be declared and directly assigned private final string name = "zhangsan";, You can also assign values in constructors or non static code blocks class Al { private final String name = "z ...

Posted by unknown on Thu, 16 Dec 2021 14:28:49 +0100

Class.getResource() and class getClassLoader(). Getresource() parsing

We wrote it on eclipse The java file will eventually be compiled into a Class bytecode file. The Java source file is stored in the src file The class bytecode file is stored in the bin file. I Pass class The getresource method returns the URL to get the file or directory public static void test1() throws Exception, FileNotFoundException{ ...

Posted by HardlyWorking on Thu, 16 Dec 2021 13:54:55 +0100

In the era of saas craze, workflow seems to be a professional quality

preface Now more and more projects begin to use workflow to meet their daily work. Today, let's take a look at the workflow of Activiti. Let's start with BPMN painting Environment installation BPMN documents about processes are mainly integrated through eclipse development tools. The idea is mainly painted by actiBPM, but actiBPM is no long ...

Posted by shwanky on Sun, 12 Dec 2021 09:34:18 +0100

Java API (DAO mode + library management system console version)

catalogue 1, Understand the idea of layered programming 2, Composition of DAO design pattern and development of each part 2.1 general 2.2 role of Dao mode 2.3 composition of Dao mode   3, Adding, deleting, modifying and searching the console version of library information management system based on DAO mode 3.1 preparation process ...

Posted by McJepp on Tue, 07 Dec 2021 20:28:15 +0100

JavaSwing (Top Container - JFrame Class)

The first step in creating a GUI program is to create a container class to accommodate other components, a common window being a container. Containers are also components that organize, manage, and display other components. 1. Overview of Top Containers          Top-level containers are the basis for ...

Posted by DarkWater on Mon, 06 Dec 2021 19:24:12 +0100

My first experience of Go + language -- Go language summary (grammar + practical problem solutions)

Introduction to Go language: As the father of C language, Go language is widely used in various fields in the future. Its grammatical features are similar to C language and more flexible. Goland Goland is a commercial version of the Jetbrains family ide Download address: Goland LiteIDE Open source go language IDE Source address: Github D ...

Posted by sumolotokai on Sun, 05 Dec 2021 07:58:37 +0100

Java object oriented (inner class)

summary If the interior of a thing contains another thing, then this is that a class contains another class. For example, the relationship between the body and the heart. Another example: the relationship between automobile and engine. Classification: 1. Member internal class 2. Local inner classes (including anonymous inner classes) Definit ...

Posted by VanPEP on Sat, 04 Dec 2021 05:08:53 +0100