Here is an example of how to use the IOContext class from the Apache Commons IO library:

import org.apache.commons.io.input.IOContext;
import org.apache.commons.io.input.TeeInputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

public class Example {
    public static void main(String[] args) throws IOException {
        // Create a FileInputStream
        FileInputStream in = new FileInputStream("/path/to/file");

        // Create a FileOutputStream
        FileOutputStream out = new FileOutputStream("/path/to/copy");

        // Create a IOContext
        IOContext context = new IOContext();

        // Create a TeeInputStream
        TeeInputStream tee = new TeeInputStream(in, out, true, context);

        // Read from the TeeInputStream
        int data = tee.read();
        while (data != -1) {
            // Process the data
            data = tee.read();
        }

        // Close the streams
        tee.close();
        out.close();
        in.close();
    }
}

In this example, the IOContext class is being used in conjunction with the TeeInputStream class to read data from a file and create a copy of it. The IOContext is used to configure the TeeInputStream to automatically close the output stream when the input stream is closed. The TeeInputStream reads data from the FileInputStream and writes it to the FileOutputStream.

The IOContext class is used to provide a context for the TeeInputStream class, which is used to pass additional configuration options to the stream. In this example, it is used to configure the stream to automatically close the output stream when the input stream is closed, but it can also be used to configure other options like buffer size, etc.

It's worth noting that the IOContext class is also used in other classes from the Apache Commons IO library like IOUtils and CountingInputStream to provide a context for those classes.