Java: accessing a List of Strings as an InputStream

Question

Is there any way InputStream wrapping a list of UTF-8 String? I\'d like to do something like:

InputStream in = new XyzInputStream( List         


        

Answer 1

In short, no, there is no way of doing this using existing JDK classes. You could, however, implement your own InputStream that read from a List of Strings.

EDIT: Dave Web has an answer above, which I think is the way to go. If you need a reusable class, then something like this might do:

public class StringsInputStream> extends InputStream {

   private ByteArrayInputStream bais = null;

   public StringsInputStream(final T strings) throws IOException {
      ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
      for (String line : strings) {
         outputStream.write(line.getBytes());
      }
      bais = new ByteArrayInputStream(outputStream.toByteArray());
   }

   @Override
   public int read() throws IOException {
      return bais.read();
   }

   @Override
   public int read(byte[] b) throws IOException {
      return bais.read(b);
   }

   @Override
   public int read(byte[] b, int off, int len) throws IOException {
      return bais.read(b, off, len);
   }

   @Override
   public long skip(long n) throws IOException {
      return bais.skip(n);
   }

   @Override
   public int available() throws IOException {
      return bais.available();
   }

   @Override
   public void close() throws IOException {
      bais.close();
   }

   @Override
   public synchronized void mark(int readlimit) {
      bais.mark(readlimit);
   }

   @Override
   public synchronized void reset() throws IOException {
      bais.reset();
   }

   @Override
   public boolean markSupported() {
      return bais.markSupported();
   }

   public static void main(String[] args) throws Exception {
      List source = new ArrayList();
      source.add("foo ");
      source.add("bar ");
      source.add("baz");

      StringsInputStream> in = new StringsInputStream>(source);

      int read = in.read();
      while (read != -1) {
         System.out.print((char) read);
         read = in.read();
      }
   }
}

This basically an adapter for ByteArrayInputStream.