DSP tutorial: Hello world

This simple example prints a line to the console, writes a line to a text file, reads it back and displays it.

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public class HelloWorld {
    public static void main(String[] args) {
        String hello = "Hello world!";
        hello = hello + " oh!";
        System.out.println(hello);

        // writing a line to a text file
        try {
            BufferedWriter outputStream = new BufferedWriter(new OutputStreamWriter(new FileOutputStream("hello.txt"),"UTF-8"));
            outputStream.write("űáéúőéú");
            outputStream.write(10);
            outputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }

        // reading and displaying a line from a text file
        BufferedReader inputStream;
        try {
            inputStream = new BufferedReader(new InputStreamReader(new FileInputStream("hello.txt"), "UTF-8"));
            System.out.println(inputStream.readLine());
            inputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

download (3.7 kb)

Compiling

Download Eclipse for Java, then extract it to your Program Files folder, and launch it. I think Eclipse is the best SDK for Java development.

Open the Hello World app in Eclipse and run it. Note: there’s a precompiled .jar file included in all tutorials. You can run .jar files by using this command line: java.exe -jar pack.jar

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Nonoo
I'm Nonoo. This is my blog about music, sounds, filmmaking, amateur radio, computers, programming, electronics and other things I'm obsessed with. ... »

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