You can write java code through script elements in JSP pages. The following article will introduce you to the script elements of JSP and how to write java code in JSP pages. I hope it will be helpful to everyone.
#Java Server Page (JSP) is a technology that uses servlets to control the content or appearance of Web pages. A small program specified in a Web page and run on the Web server to modify the Web page before sending it to the user who requested it. [Video tutorial recommendation: Java tutorial]
Types of JSP script elements
Script elements are provided in jsp The ability to insert java code. There are three types of script elements:
Script (scriptlet):
is a container for Java code snippets in a JSP page. When converting a page to a servlet class, the scriptlet content is inserted into the jspService() method of the servlet class, and the servlet is generated from the JSP. The syntax is as follows:
<% java源代码 %>
Expression (expression):
is used to insert the value of a Java expression converted to String into the response returned to the client middle. The syntax is as follows:
<%= 表达式语句 %>
Declarations:
is used to declare global methods and variables for the JSP page. In a JSP file, these variables and methods must be declared before they can be used.
In page conversion, the declared methods and variables become class member declarations in the servlet class of the JSP page. The syntax is as follows:
<%! 字段或方法声明 %>
Code example
The following is a simple example to introduce the use of these three script elements
Example One: scriptlet
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%> //中文编码
<!DOCTYPE html>
<html>
<head><title>Hello World</title></head>
<body>
Hello World!<br/>
<%
out.println("Your IP address is " + request.getRemoteAddr());
%>
</body>
</html>Example two: expression
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%> //中文编码
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>菜鸟教程(runoob.com)</title>
</head>
<body>
<p>
今天的日期是: <%= (new java.util.Date()).toLocaleString()%>
</p>
</body>
</html>Example three: declarations
<%! int i = 0; %> <%! int a, b, c; %> <%! Circle a = new Circle(2.0); %>
The above is the entire content of this article , I hope it can be helpful to everyone’s study. For more exciting content, you can pay attention to the relevant tutorial columns of the PHP Chinese website! ! !
The above is the detailed content of How to write java code inside JSP page? (code example). For more information, please follow other related articles on the PHP Chinese website!
Java Platform Independence: What does it mean for developers?May 08, 2025 am 12:27 AMJava'splatformindependencemeansdeveloperscanwritecodeonceandrunitonanydevicewithoutrecompiling.ThisisachievedthroughtheJavaVirtualMachine(JVM),whichtranslatesbytecodeintomachine-specificinstructions,allowinguniversalcompatibilityacrossplatforms.Howev
How to set up JVM for first usage?May 08, 2025 am 12:21 AMTo set up the JVM, you need to follow the following steps: 1) Download and install the JDK, 2) Set environment variables, 3) Verify the installation, 4) Set the IDE, 5) Test the runner program. Setting up a JVM is not just about making it work, it also involves optimizing memory allocation, garbage collection, performance tuning, and error handling to ensure optimal operation.
How can I check Java platform independence for my product?May 08, 2025 am 12:12 AMToensureJavaplatformindependence,followthesesteps:1)CompileandrunyourapplicationonmultipleplatformsusingdifferentOSandJVMversions.2)UtilizeCI/CDpipelineslikeJenkinsorGitHubActionsforautomatedcross-platformtesting.3)Usecross-platformtestingframeworkss
Java Features for Modern Development: A Practical OverviewMay 08, 2025 am 12:12 AMJavastandsoutinmoderndevelopmentduetoitsrobustfeatureslikelambdaexpressions,streams,andenhancedconcurrencysupport.1)Lambdaexpressionssimplifyfunctionalprogramming,makingcodemoreconciseandreadable.2)Streamsenableefficientdataprocessingwithoperationsli
Mastering Java: Understanding Its Core Features and CapabilitiesMay 07, 2025 pm 06:49 PMThe core features of Java include platform independence, object-oriented design and a rich standard library. 1) Object-oriented design makes the code more flexible and maintainable through polymorphic features. 2) The garbage collection mechanism liberates the memory management burden of developers, but it needs to be optimized to avoid performance problems. 3) The standard library provides powerful tools from collections to networks, but data structures should be selected carefully to keep the code concise.
Can Java be run everywhere?May 07, 2025 pm 06:41 PMYes,Javacanruneverywhereduetoits"WriteOnce,RunAnywhere"philosophy.1)Javacodeiscompiledintoplatform-independentbytecode.2)TheJavaVirtualMachine(JVM)interpretsorcompilesthisbytecodeintomachine-specificinstructionsatruntime,allowingthesameJava
What is the difference between JDK and JVM?May 07, 2025 pm 05:21 PMJDKincludestoolsfordevelopingandcompilingJavacode,whileJVMrunsthecompiledbytecode.1)JDKcontainsJRE,compiler,andutilities.2)JVMmanagesbytecodeexecutionandsupports"writeonce,runanywhere."3)UseJDKfordevelopmentandJREforrunningapplications.
Java features: a quick guideMay 07, 2025 pm 05:17 PMKey features of Java include: 1) object-oriented design, 2) platform independence, 3) garbage collection mechanism, 4) rich libraries and frameworks, 5) concurrency support, 6) exception handling, 7) continuous evolution. These features of Java make it a powerful tool for developing efficient and maintainable software.
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
SublimeText3 English version
Recommended: Win version, supports code prompts!
SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.
ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment
Dreamweaver Mac version
Visual web development tools
WebStorm Mac version
Useful JavaScript development tools
