Filter (search and replace) array of bytes in an InputStream

Question

I have an InputStream which takes the html file as input parameter. I have to get the bytes from the input stream .

I have a string: \"XYZ\". I\'d like

Answer 1

I came up with this simple piece of code when I needed to serve a template file in a Servlet replacing a certain keyword by a value. It should be pretty fast and low on memory. Then using Piped Streams I guess you can use it for all sorts of things.

/JC

public static void replaceStream(InputStream in, OutputStream out, String search, String replace) throws IOException
{
    replaceStream(new InputStreamReader(in), new OutputStreamWriter(out), search, replace);
}

public static void replaceStream(Reader in, Writer out, String search, String replace) throws IOException
{
    char[] searchChars = search.toCharArray();
    int[] buffer = new int[searchChars.length];

    int x, r, si = 0, sm = searchChars.length;
    while ((r = in.read()) > 0) {

        if (searchChars[si] == r) {
            // The char matches our pattern
            buffer[si++] = r;

            if (si == sm) {
                // We have reached a matching string
                out.write(replace);
                si = 0;
            }
        } else if (si > 0) {
            // No match and buffered char(s), empty buffer and pass the char forward
            for (x = 0; x < si; x++) {
                out.write(buffer[x]);
            }
            si = 0;
            out.write(r);
        } else {
            // No match and nothing buffered, just pass the char forward
            out.write(r);
        }
    }

    // Empty buffer
    for (x = 0; x < si; x++) {
        out.write(buffer[x]);
    }
}