Duplicate and rename Java files

Oct 13, 2025 by pynkocean.com 124 views

Introduction

When working with multiple files having the same name but different extensions, it can be tedious to duplicate and rename them individually. This is particularly true when dealing with large projects that involve multiple files with the same name but different extensions. In this article, we will explore a simple way to duplicate and rename files with matching names but different extensions in bash.

Understanding the Problem

Let's consider a scenario where we have two files, foo.cpp and foo.h, and we want to duplicate them and rename the copies to bar.cpp and bar.h, respectively. We can achieve this using the cp command, but it would require two separate commands:

cp foo.cpp bar.cpp
cp foo.h bar.h

This approach is not only time-consuming but also prone to errors, especially when dealing with multiple files.

Using Bash's Wildcard Expansion

Bash provides a feature called wildcard expansion, which allows us to use patterns to match files. We can use this feature to duplicate and rename files with matching names but different extensions in a single command.

cp foo.{cpp,h} bar.{cpp,h}

In this command, foo.{cpp,h} is a pattern that matches both foo.cpp and foo.h files. Similarly, bar.{cpp,h} is a pattern that matches both bar.cpp and bar.h files. When we use the cp command with these patterns, it will duplicate and rename the files accordingly.

How it Works

When we use the cp command with wildcard expansion, bash expands the pattern to match the actual file names. In this case, foo.{cpp,h} is expanded to foo.cpp and foo.h, and bar.{cpp,h} is expanded to bar.cpp and bar.h. The cp command then duplicates and renames the files accordingly.

Using Regular Expressions

Bash also provides support for regular expressions, which can be used to match complex patterns. We can use regular expressions to duplicate and rename files with matching names but different extensions in a single command.

cp foo\.[ch] bar\.[ch]

In this command, foo\.[ch] is a regular expression that matches both foo.cpp and foo.h files. Similarly, bar\.[ch] is a regular expression that matches both bar.cpp and bar.h files. When we use the cp command with these regular expressions, it will duplicate and rename the files accordingly.

Tips and Variations

Here are some tips and variations to keep in mind when using wildcard expansion and regular expressions to duplicate and rename files:

Use quotes: When using wildcard expansion or regular expressions, it's a good idea to use quotes to prevent bash from expanding the pattern prematurely.
Use the -i option: If you want to be prompted before overwriting existing files, use the -i option with the cp command.
Use the -r option: If you want to recursively copy files and directories, use the -r option with the cp command.
Use the --verbose option: If you want to see the files being copied, use the --verbose option with the cp command.

Conclusion

In this article, we explored a simple way to duplicate and rename files with matching names but different extensions in bash. We used wildcard expansion and regular expressions to achieve this in a single command. By using these techniques, you can save time and reduce errors when working with multiple files with the same name but different extensions.

Example Use Cases

Here are some example use cases for duplicating and renaming files with matching names but different extensions:

Duplicate and rename C++ files: cp foo.{cpp,h} bar.{cpp,h}
Duplicate and rename Java files: cp foo.{java,properties} bar.{java,properties}
Duplicate and rename Python files: cp foo.{py,txt} bar.{py,txt}

Introduction

In our previous article, we explored a simple way to duplicate and rename files with matching names but different extensions in bash. We used wildcard expansion and regular expressions to achieve this in a single command. In this article, we will answer some frequently asked questions about duplicating and renaming files with matching names but different extensions in bash.

Q: What is wildcard expansion in bash?

A: Wildcard expansion is a feature in bash that allows us to use patterns to match files. We can use this feature to duplicate and rename files with matching names but different extensions in a single command.

Q: How do I use wildcard expansion to duplicate and rename files?

A: To use wildcard expansion to duplicate and rename files, you can use the following command:

cp foo.{cpp,h} bar.{cpp,h}

Q: What is the difference between wildcard expansion and regular expressions?

A: Wildcard expansion and regular expressions are both used to match patterns in bash. However, wildcard expansion is a simpler and more straightforward way to match patterns, while regular expressions are more powerful and flexible.

Q: How do I use regular expressions to duplicate and rename files?

A: To use regular expressions to duplicate and rename files, you can use the following command:

cp foo\.[ch] bar\.[ch]

Q: What are some common use cases for duplicating and renaming files with matching names but different extensions?

A: Some common use cases for duplicating and renaming files with matching names but different extensions include:

Duplicate and rename C++ files: cp foo.{cpp,h} bar.{cpp,h}
Duplicate and rename Java files: cp foo.{java,properties} bar.{java,properties}
Duplicate and rename Python files: cp foo.{py,txt} bar.{py,txt}

Q: How do I prevent bash from expanding the pattern prematurely?

A: To prevent bash from expanding the pattern prematurely, you can use quotes around the pattern. For example:

cp "foo.{cpp,h}" "bar.{cpp,h}"

Q: How do I recursively copy files and directories?

A: To recursively copy files and directories, you can use the -r option with the cp command. For example:

cp -r foo bar

This will recursively copy the foo directory and all its contents to the bar directory.

Q: How do I see the files being copied?

A: To see the files being copied, you can use the --verbose option with the cp command. For example:

cp --verbose foo bar

This will display the files being copied and their sizes.

Conclusion

In this article, we answered some frequently asked questions about duplicating and renaming files with matching names but different extensions in bash. We covered topics such as wildcard expansion, regular expressions, and common use cases. By using the techniques described in this article, you can easily duplicate and rename files with matching names but different extensions in bash.