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!
How do I use Maven or Gradle for advanced Java project management, build automation, and dependency resolution?Mar 17, 2025 pm 05:46 PMThe article discusses using Maven and Gradle for Java project management, build automation, and dependency resolution, comparing their approaches and optimization strategies.
How do I create and use custom Java libraries (JAR files) with proper versioning and dependency management?Mar 17, 2025 pm 05:45 PMThe article discusses creating and using custom Java libraries (JAR files) with proper versioning and dependency management, using tools like Maven and Gradle.
How do I implement multi-level caching in Java applications using libraries like Caffeine or Guava Cache?Mar 17, 2025 pm 05:44 PMThe article discusses implementing multi-level caching in Java using Caffeine and Guava Cache to enhance application performance. It covers setup, integration, and performance benefits, along with configuration and eviction policy management best pra
How can I use JPA (Java Persistence API) for object-relational mapping with advanced features like caching and lazy loading?Mar 17, 2025 pm 05:43 PMThe article discusses using JPA for object-relational mapping with advanced features like caching and lazy loading. It covers setup, entity mapping, and best practices for optimizing performance while highlighting potential pitfalls.[159 characters]
How does Java's classloading mechanism work, including different classloaders and their delegation models?Mar 17, 2025 pm 05:35 PMJava's classloading involves loading, linking, and initializing classes using a hierarchical system with Bootstrap, Extension, and Application classloaders. The parent delegation model ensures core classes are loaded first, affecting custom class loa
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
AI Hentai Generator
Generate AI Hentai for free.
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.
SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.
VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft
EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function
