I apologize, but there is no such class as "TokenFilterContext" in the Apache Commons IO library. It seems that you might be confusing it with other class or package.

Apache Commons IO provides several classes for working with files and IO operations, but it doesn't have any class with the name "TokenFilterContext" and doesn't have any feature related to it.

If you are looking for a way to filter or process text by tokens and need to keep track of additional information during the processing, you could create your own class that implements the TokenFilter interface and stores the additional information as member variables.

Here is an example of creating a simple TokenFilter implementation:

import java.util.StringTokenizer;

public class MyTokenFilter implements TokenFilter {
    private StringTokenizer tokenizer;
    private String currentToken;
    private String prefix;

    public MyTokenFilter(String input, String prefix) {
        this.tokenizer = new StringTokenizer(input);
        this.prefix = prefix;
    }

    public boolean hasNext() {
        return tokenizer.hasMoreTokens();
    }

    public String next() {
        currentToken = tokenizer.nextToken();
        return prefix + currentToken;
    }

    public String getCurrentToken() {
        return currentToken;
    }
}

In this example, we first create a StringTokenizer object using the input string and the default delimiter (whitespace). We then use a while loop to iterate over the tokens, and the hasNext() method to check if there are more tokens to process, and the next() method to get the next token.

You can use this class as follows:

MyTokenFilter filter = new MyTokenFilter("This is a test string.", "prefix:");
while (filter.hasNext()) {
    String token = filter.next();
    System.out.println(token);
}

This example will output:

prefix:This
prefix:is
prefix:a
prefix:test
prefix:string.