14 08 playback of files

In the previous lesson we used FileWriter to put text into a file. This lesson focuses on reading a Java text file back from disk. To keep the example tidy we wrap the read logic in a small helper method and pass the file (or the filename) as a parameter, instead of hard-coding it inside main.

Just like the writing example, reading throws checked exceptions, so the call site has to deal with them. We wrap the read operations inside a try/catch block and report any IOException in the catch. Java offers several reader classes for this. The most common starting point is FileReader, which deals with character streams.

Reading character by character

  • Create a FileReader with the file path: FileReader reader = new FileReader("file.txt");.
  • Use a loop to call read() repeatedly. The method returns the next character as an int, or -1 when the file ends.
  • Print or accumulate the characters as you go.
  • Close the reader once the loop exits to release the file handle.

That is the minimal pattern for reading a small text file. In the next lessons we will build a slightly larger project that ties writing and reading together with structured data such as student records, and we will look at higher level classes like BufferedReader that make line-oriented reading more convenient.

Overall, the playback of files module in Java is a powerful tool for developers who want to add media playback functionality to their applications. It provides a robust and flexible solution for handling media files and can be used in a wide range of applications, from music players to video editing software.

Summary

This lesson teaches how to read and playback files in Java by creating variables and passing them as parameters. The instructor explains that multiple methods are available for file reading operations, helping to simplify the process through proper variable management and parameterization.

Key points

  • How to read files in Java using variables and parameters
  • Multiple methods exist for file reading operations
  • Simplifying file operations by passing variables as parameters
  • Proper code organization for file handling tasks

FAQ

What are the main methods for reading files in Java?

The lesson demonstrates that several methods are available for reading files in Java, which are implemented by creating variables and passing them as parameters to simplify operations.

Why should variables be passed as parameters when reading files?

Passing variables as parameters helps simplify file operations and makes the code more organized and reusable across different file-reading scenarios.