HttpServletRequest getPart(") not found - servlets

Question

I don't know why it is not working.
I am trying to accept multipart-formdata in my servlet but request.getPart("") is not showing. I am using glassfish 3.1.2 server. Tha framework used is vaadin for developing application. Can any one help me to fix this problem?

Answer 1

Assuming that your concrete problem is indeed that your IDE didn't show the getPart() method on autocomplete, then that can only mean that the project is not configured as a Servlet 3.0 compatible project. That method was namely introduced in Servlet 3.0.
You didn't tell anything about which IDE exactly you're using and your question history doesn't give any clues as well, so let's assume that it's Eclipse which is rather widely used. In that case, you need to configure it at 2 places, provided that you've correctly associated the Dynamic Web Project with a Servlet 3.0 compatible container as Targeted Runtimes in project's properties (otherwise HttpServletRequest and consorts wouldn't have compiled at all):
In the Project Facets section of project's properties, the Dynamic Web Module version must be set to 3.0.
If your IDE has generated a /WEB-INF/web.xml file, then you need to make sure that its <web-app> root declaration also matches Servlet 3.0, otherwise it would still fail during runtime.
<?xml version="1.0" encoding="UTF-8"?>
<web-app
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
version="3.0">
</web-app>

Answer 2

I had the same problem. Here's what eventually turned out to be the problem for me. I had a dependency on:
<dependency>
<groupId>com.googlecode.jsontoken</groupId>
<artifactId>jsontoken</artifactId>
<version>1.1</version>
</dependency>
And it turned out jsontoken has a dependency on servlet-api 2.5. So what fixed the problem was simply this:
<dependency>
<groupId>com.googlecode.jsontoken</groupId>
<artifactId>jsontoken</artifactId>
<version>1.1</version>
<exclusions>
<exclusion>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
</exclusion>
</exclusions>
</dependency>

Answer 3

This worked for me
<!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>4.0.1</version>
<scope>provided</scope>
</dependency>

Answer 4

To those that stumble on this later, if the resolution suggested by BalusC does not resolve the problem for you please check your build path for provided libraries whose runtime does not match the runtime of your server.
For example if your maven pom.xml contains entries that provide java EE libraries like so...
<dependency>
<groupId>org.apache.openejb</groupId>
<artifactId>javaee-api</artifactId>
<version>5.0-1</version>
<scope>provided</scope>
</dependency>
... they can interfere with what your IDE perceives as the runtime environment, which will be used to provide code completion suggestions.
The easiest way to track the problem is to figure out where the HttpServletRequest class is sourced from.

Answer 5

maven.. pom.xml.. modify this dependency
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.0.1</version>
</dependency>
servlet api 2.5 is not work

Answer 6

I had the same problem, I want to share it with you in case anyone else bumps in the same problem:
In my case I had a j2ee.jar which was automatically downloaded and its version was probably old. It was located under Libraries --> j2ee Runtime Library (stackoverflow doesn't let me add an image so in eclipse - in Project Explorer - expand the project --> Java Resources --> libraries --> J2ee Runtime Library --> j2ee.jar)
I went to the file system where this file was located (you have the location next to the file in eclipse) and replaced it with a newer jar. You can take the jar from here.
Then clean and rebuild the project.

Answer 7

One possible reason, as pointed out in Bjørn's answer, is a conflicting artifact servlet-api (Servlet 2.5 spec).
In my case it was this dependency
<groupId>com.google.api-client</groupId>
<artifactId>google-api-client-appengine</artifactId>
<version>1.30.10</version>
To find out which dependency compiles the conflicting library just build and print the dependency tree with:
mvn org.apache.maven.plugins:maven-dependency-plugin:2.10:tree -Dverbose=true
Part of the output:
Finally exclude the artifact from the dependency
<dependency>
<groupId>com.google.api-client</groupId>
<artifactId>google-api-client-appengine</artifactId>
<version>1.30.10</version>
<exclusions>
<exclusion>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
</exclusion>
</exclusions>
</dependency>

Answer 8

Hi friends I too faced simillar problem and I will tell you what I did.
I'm using eclipse juno and Tomcat 7 server. Make sure you use latest servlet API jar. Tomcat 7 will only support dynamic module version 2.5 not more than that. So use higher Tomcat version or lower dynamic module version then it will work.
One more thing: open your servlet api jar and see whether it contains "Part" you can easily check it.