Sometimes we encounter this problem during the development process. el expressions and jstl tags cannot be used. This is really a disaster for lazy people. Not only do you have to write a lot more code, but the page will also look very bloated. I hope some methods in this article can help you.
As shown in the figure below:
First we need to ensure that all required maven dependencies are added
<dependencies> <dependency> <groupid>junit</groupid> <artifactid>junit</artifactid> <version>3.8.1</version> <scope>test</scope> </dependency> <dependency> <groupid>javax.servlet</groupid> <artifactid>javax.servlet-api</artifactid> <version>3.1.0</version> </dependency> <dependency> <groupid>javax.servlet</groupid> <artifactid>jsp-api</artifactid> <scope>provided</scope> <version>2.0</version> </dependency> <dependency> <groupid>mysql</groupid> <artifactid>mysql-connector-java</artifactid> <version>5.1.25</version> </dependency> <dependency> <groupid>jstl</groupid> <artifactid>jstl</artifactid> <version>1.2</version> </dependency> <dependency> <groupid>taglibs</groupid> <artifactid>standard</artifactid> <version>1.1.2</version> </dependency> </dependencies>
After adding relevant dependencies, if the above situation still cannot be displayed normally, you can try the following solutions:
I think this is not a JSTL problem, ${emp.role} is EL (expression language), it doesn't work.
We can set it in the JSP file
or set it in web.xml
<el-ignored>true</el-ignored>
It should be false by default, but if the servlet version you are using is lower than 2.4, then Default is true, so in this case you need to set it to false in web.xml:
*.jsp <el-ignored>true</el-ignored>
You have 3.1 dependency version but are using web.xml file with 2.3 version . To use Servlet 3.1 try to change your web.xml to:
<web-app> rest of the TAGs </web-app>
The effect after modification:
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