如何解决Java Web应用中com.sun.jersey.servlet.ServletContainer类找不到异常

The error you're seeing means your Apache server can't locate the Jersey ServletContainer class required to run your RESTful endpoints. This almost always happens because the jersey-servlet JAR file isn't being included in the WEB-INF/lib directory of your deployed helloWorld WAR application.

Here's how to resolve this step-by-step:

1. Verify the Jersey Servlet JAR is present in your WAR #

First, check if jersey-servlet-1.17.1.jar exists inside the WEB-INF/lib folder of your deployed WAR. If it's missing, Maven isn't packaging the dependency correctly into your build.

To fix this:

• Run the Maven command to clean and rebuild your project:

  mvn clean package
  

  This ensures all dependencies are pulled and packaged into the WAR file located in the target directory.

2. Check your IDE's deployment configuration (if using Eclipse/IntelliJ) #

If you're using an IDE to deploy your app, it might not include Maven dependencies by default:

• Eclipse:
  1. Right-click your project > Properties > Deployment Assembly.
  2. Look for an entry named "Maven Dependencies". If missing, click "Add" > "Java Build Path Entries" > select "Maven Dependencies" > Finish.
  3. Ensure it's mapped to the /WEB-INF/lib path.
• IntelliJ:
  1. Go to File > Project Structure > Artifacts.
  2. Select your WAR artifact, then expand the "WEB-INF/lib" section.
  3. If jersey-servlet-1.17.1.jar isn't listed, click the "+" button > "Library Files" > select the jersey-servlet dependency > OK.

3. Confirm your pom.xml dependency configuration #

Double-check that your jersey-servlet dependency doesn't have an incorrect scope that would exclude it from the WAR. Your current configuration is correct, but ensure there's no <scope>provided</scope> tag (which tells Maven not to package the JAR, assuming the server provides it):

<dependency>
    <groupId>com.sun.jersey</groupId>
    <artifactId>jersey-servlet</artifactId>
    <version>1.17.1</version>
    <!-- No <scope> tag here is correct for packaging into the WAR -->
</dependency>

4. Clear server cache and redeploy #

Sometimes old cached files can cause issues:

• Stop your Apache server.
• Delete the work directory (for Tomcat, this is usually in tomcat_home/work).
• Delete the deployed helloWorld folder from the webapps directory.
• Deploy the freshly built WAR from the target folder again.

Following these steps should resolve the ClassNotFoundException and let your Jersey servlet load correctly.

内容的提问来源于stack exchange，提问作者A.Aou