jstack java stack tracing tool 1. Introduction to jstack jstack (stack trace for java) is a stack tracing tool that comes with the Java virtual machine. jstack is mainly used to generate a thread snapshot of the current moment of the Java virtual machine. The thread snapshot is the method currently being executed by each […]
Tag: jst
EL expressions and JSTL tag library
2023.10.25 What is EL expression? EL expression, Expression Language, can replace the java code in JSP, making the program in the JSP file look cleaner and more beautiful. Since JSP is mixed with various java codes, such as , , etc., the JSP file is very confusing and difficult to maintain, so EL expressions are […]
JVM | Command line diagnosis and tuning jhsdb jmap jstat jps
Table of Contents jmap View heap usage View the class list, including the number of instances and memory size occupied Generate heap dump snapshot dump file of jvm jstat View gc information, check the number of gc times, and time Check the usage and size of three generations (young/old/perm) objects in VM memory View metadata […]
Java thread monitoring jvisualvm and jstack
Five states of threads New: new Run: runnable Waiting: waiting (waiting indefinitely), timed waiting (waiting within a time limit) blocked: blocked End: terminated Thread conversion relationship Two monitoring methods for threads 1. Graphical interface method: jvisualvm Before monitoring, first add monitoring parameters to the jvm. In the catalina.sh file in the bin directory of tomcat, […]
JSP Standard Tag Library (JSTL) Personal User Guide
As a reminder, this article only covers the configuration of JSTL and briefly introduces several commonly used tags in JSTL’s Core and Functions tag libraries. For more detailed content, the blogger will post corresponding hyperlinks. Note: This tutorial uses JSTL 1.2. If you are using JSTL 1.1 or a previous version, you need to import […]
The use of javaee springMVC Map ModelMap ModelAndView el and jstl
pom dependencies <?xml version=”1.0″ encoding=”UTF-8″?> <project xmlns=”http://maven.apache.org/POM/4.0.0″ xmlns:xsi=”http://www.w3.org/2001/XMLSchema-instance” xsi:schemaLocation=”http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd”> <modelVersion>4.0.0</modelVersion> <groupId>org.example</groupId> <artifactId>TestSpringMVC3</artifactId> <version>1.0-SNAPSHOT</version> <packaging>war</packaging> <name>TestSpringMVC3 Maven Webapp</name> <!– FIXME change it to the project’s website –> <url>http://www.example.com</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <maven.compiler.source>1.7</maven.compiler.source> <maven.compiler.target>1.7</maven.compiler.target> </properties> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> <scope>test</scope> </dependency> <!– Spring –> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> […]
CGLIB proxy, jsp, EL expression, JSTL standard tag library
1. CGLIB agent There is a class that does not implement the interface. If you want to enhance this class, you need to use the CGLIB proxy Import CGLIB package <dependency> <groupId>cglib</groupId> <artifactId>cglib</artifactId> <version>3.3.0</version> </dependency> Write the proxied class package com.wz.practice.proxy.cglib; public class UserService { public void add(){ System.out.println(“——–add execution——–“); } public void update(){ System.out.println(“——–update […]
JavaWeb Speedthrough EL and JSTL
Directory 1. EL expression 1. Quick Start : 1.1 Basic introduction 1.2 Getting Started Case 2. Commonly used output formats: 2.1 Create JavaBean class 2.2 Create JSP file 3.empty operator: 3.1 Introduction 3.2 Examples 4. EL object: 4.1 EL11 built-in objects 4.2 Domain Object Demonstration 4.3 Get HTTP information Two, JSTL tag library 1. Basic […]
el expression and jstl tag library
el expressions are only used in jsp pages. The role of the el expression when it was first proposed: 1. Data can be obtained from domain objects. easier. ${expression to get domain object content} pageContext request session application 2. The second usage is to write various operations in el expressions. Arithmetic comparison operation logic operation […]
EL expression & JSTL tag library
1. What is EL expression and what does EL expression do? The full name of EL expression is: Expression Language. is an expression language. What is the function of EL expression: EL expression mainly replaces the expression script in the jsp page to output data in the jsp page. Because EL expressions are much more […]