public class UploadFile
{
      public static void main(String a[])
      {
            try
            {
                  String auth_token = "USER AUTH TOKEN"; 
                  String auth_scope = "crmapi";
                  String targetURL = "https://crm.zoho.com/crm/private/xml/Leads/uploadFile";
                  String recordId = "RECORD ID";
                  String file = "FILE NAME";
                  File f = new File(file);
                  FileInputStream fis = new FileInputStream(f);
                  ByteArrayOutputStream bos = new ByteArrayOutputStream();
                  int c;
                  while ((c = fis.read()) != -1)
                  {
                        bos.write(c);
                  }
                  byte[] fbArray = bos.toByteArray();
                  targetURL = targetURL + "?authtoken="+ auth_token +"&scope="+ auth_scope;
                  PartSource ps = new ByteArrayPartSource(file,fbArray);
                  PostMethod post =new PostMethod(targetURL);
                  Part[] fields = { new FilePart("content",ps), new StringPart("id", recordId), };
                  post.setRequestEntity(new MultipartRequestEntity(fields,post.getParams()));
                  HttpClient httpclient = new HttpClient();
                  httpclient.executeMethod(post);
                  String postResp = post.getResponseBodyAsString();
                  System.out.println("postResp===========> : "+postResp);
            }
            catch(Exception e)
            {
                  e.printStackTrace();
            }
      }
}