Telegram Bot开发报错：无法访问CompletableFuture类文件

It looks like you're hitting two key issues here: an incorrect project directory structure and a Java version mismatch. Let's break down how to fix both:

1. Correct Your Project Directory Structure #

Looking at the error path:

C:\Users\safwa\Documents\IntelliJ\assignment-2-safwan0908\src\main\java\my\assignment2\src\main\java\org\example\s261251Bot.java

Your source files are nested inside a duplicate src/main/java directory, which confuses the compiler. Here's how to fix it:

• Navigate to your project folder: assignment-2-safwan0908/src/main/java/my/assignment2/src/main/java/
• Move the org folder (containing your example package and bot files) directly into the outer src/main/java folder (so it becomes assignment-2-safwan0908/src/main/java/org/example/)
• Delete the now-empty nested directories (my/assignment2/src/main/java/)
• Refresh your project in IntelliJ (right-click the project root > Refresh)

2. Ensure You're Using Java 8 or Higher #

java.util.concurrent.CompletableFuture was introduced in Java 8. If your project is set to use an older Java version, the compiler won't find this class. Here's how to update it in IntelliJ:

• Go to File > Project Structure (or press Ctrl+Alt+Shift+S)
• Under Project Settings > Project:
  • Set Project SDK to Java 8 (or a newer version like Java 11/17) – if you don't have it installed, download it from Oracle or OpenJDK first
  • Set Project language level to 8 - Lambdas, type annotations etc. or higher
• Under Project Settings > Modules:
  • Select your module, go to the Sources tab, and set Language level to match the project level (8+)
• If you're using Maven, add these lines to your pom.xml to enforce Java 8:

  <properties>
      <maven.compiler.source>1.8</maven.compiler.source>
      <maven.compiler.target>1.8</maven.compiler.target>
  </properties>
  

• If you're using Gradle, add this to your build.gradle:

  sourceCompatibility = 1.8
  targetCompatibility = 1.8
  

3. Clean and Rebuild the Project #

After fixing the structure and Java version:

• Go to Build > Clean Project
• Then Build > Rebuild Project
• Run your App.java again

These steps should resolve the missing CompletableFuture error and get your Telegram Bot running.

内容的提问来源于stack exchange，提问作者X unknown