Java: How to Set Proxy on HttpURLConnection

If you need to set proxy address on Java HttpURLConnection. Do something like below.

public static String getString(String urlStr) throws Exception
{
    HttpURLConnection connection = null;
    InputStream is = null;
    try
    {
        URI uri = new URI(urlStr);

        // settin proxy
        String proxyHost = ""; // your proxy serever address
        int proxyPort = 8080;  // your proxy port
        Proxy proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress(proxyHost, proxyPort));

        // open connection with passing Proxy Object
        connection = (HttpURLConnection)uri.toURL().openConnection(proxy);

        connection.connect();
        is = connection.getInputStream();
        String content = toString(is);
        return content;
    }
    finally{
        closeQuietly(is);
         
        if(connection != null)
        {
           connection.disconnect();
        }
    }
}

private static String toString(InputStream is) throws IOException
{
    byte[] buf = new byte[1024];
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    for(int len = is.read(buf); len > 0; len = is.read(buf))
    {
        baos.write(buf, 0, len);
    }
    return baos.toString();
}

private static void assertNotNull(Object object, String message)
{
    if(object == null)
    {
        throw new IllegalArgumentException(message);
    }
}

private static void closeQuietly(Closeable closeable)
{
   if(closeable != null)
   {
       try {
           closeable.close();
       } catch (IOException e) {
       }
    }
       
}

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