如何在终端编译运行含Jar包与TXT文件的Java项目及排障

Hey Anna, let's break down why your code works smoothly in the IDE but throws a file-not-found error when running from the terminal, and walk through simple fixes to get it working.

What's Causing the Error? #

The Exception in thread "main" java.io.FileNotFoundException: src/out.txt (No such file or directory) issue comes down to mismatched relative file paths:

• When you run java -cp .:jsoup-1.11.3.jar Main from the src directory, your program's working directory is set to src.
• But your Writer class is trying to access src/out.txt—this means the program is actually looking for src/src/out.txt (since paths are relative to the current working directory), which doesn't exist. That's where the error originates.

Solutions to Try #

1. Run the Program from the Correct Working Directory #

The easiest fix is to navigate back to your Task_3 directory (the parent folder of src) and run the command from there. This way, the relative path src/out.txt will point to the actual file location:

# First go back to the Task_3 directory, then run:
java -cp src:lib/jsoup-1.11.3.jar Main

• -cp src:lib/jsoup-1.11.3.jar tells Java to look for compiled classes in the src directory and include the jsoup jar from the lib folder.

2. Adjust the File Path in Your Code #

If you prefer to run the program directly from the src directory, modify the file path in your Writer class to target the file without the src/ prefix:

// Update your path-related code to this:
String fs = System.getProperty("file.separator");
String filePath = "out.txt"; // This targets out.txt in your current working directory

Now when you run from src, the program will create or read out.txt directly in that folder, eliminating path confusion.

Bonus: Clean Up Compiled File Organization #

Your current compile command places .class files right alongside your .java source files in src. For a more standard, organized setup, specify an output directory (like bin) when compiling:

# Run this from the Task_3 directory:
javac -cp lib/*.jar -d bin src/*.java

Then run the program using:

java -cp bin:lib/jsoup-1.11.3.jar Main

This keeps your source code and compiled classes separate, which is a common best practice for Java projects.

内容的提问来源于stack exchange，提问作者Anna F