ConnectionImpl.java

package com.coderising.download.impl;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;

import com.coderising.download.api.Connection;
import com.coderising.download.api.ConnectionManager;


public class ConnectionImpl implements Connection {

	private static int buffer_size = 1024;
	private ConnectionManager cm;
	private HttpURLConnection httpConn;
	private URL url;
	private boolean finished = false;

	public ConnectionImpl(ConnectionManager cm, String _url) {
		this.cm = cm;
		try {
			url = new URL(_url);
			httpConn = (HttpURLConnection) url.openConnection();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	@Override
	public void close() {
		httpConn.disconnect();
	}

	@Override
	public int getContentLength() {
		int len = httpConn.getContentLength();

		return len;

	}

	@Override
	public String getFileName() {
		String fileName = httpConn.getURL().getFile();
		fileName = fileName.substring(fileName.lastIndexOf('/') + 1);
		return fileName;
	}

	@Override
	public boolean isFinished() {
		return finished;
	}

	@Override
	public byte[] read(int startPos, int endPos) throws IOException {
		InputStream in = null;
		ByteArrayOutputStream out = null;
		try {
			httpConn = (HttpURLConnection) url.openConnection();
			httpConn.setRequestProperty("Range", "bytes=" + startPos + "-" + endPos);
			in = httpConn.getInputStream();
			out = new ByteArrayOutputStream();
			in = httpConn.getInputStream();
			// in.skip(startPos);

			int len = 0;
			byte[] b = new byte[1024];
			while ((len = in.read(b)) != -1) {
				out.write(b, 0, len);
			}
			int totalLen = endPos - startPos + 1;

			if (out.size() > totalLen) {
				byte[] data = out.toByteArray();
				return data;
			}

			return out.toByteArray();

		} catch (IOException e) {
			e.printStackTrace();
		}
		return null;
	}

	@Override
	public void setFinished() {
		finished = true;
	}

}