Android แอพพลิเคชันแอนดรอย ที่ใช้ database ผ่าน web service จะปฏิเสธการรับ input ว่างจาก edittext ยังไงหรอครับ

public String addEmployee(int id, String firstname, String lastname,
			int age, String jobs) {
		if (checkID(id) == false) {
			return "No this id";
		} else if (firstname.trim().equals("")) {//มันไม่ยอม return ค่า แต่รันผ่านไปปกติเลย
			return "Please Insert First Name";
		} else if (lastname.trim().equals("")) {
			return "Please Insert Last Name";
		} else if (age == 0) {
			return "Age Error";
		} else if (jobs.trim().equals("")) {
			return "Please Insert Your Job";
		} else {
			connect();
			try {
				stmt.executeUpdate("INSERT INTO TEST:Employee VALUES(" + id
						+ ",'" + firstname.trim() + "','" + lastname.trim()
						+ "'," + age + ",'" + jobs.trim() + "')");
				conn.commit();
			} catch (SQLException e) {
				e.printStackTrace();
			} finally {
				close();
			}
			System.out.println("Employee Added");
			return "Employee Added";
		}
	}

Button submit = (Button) this.findViewById(R.id.btsubmit);
		submit.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {

				EditText id = (EditText) findViewById(R.id.edtid);
				EditText fname = (EditText) findViewById(R.id.edtfname);
				EditText lname = (EditText) findViewById(R.id.edtlname);
				EditText age = (EditText) findViewById(R.id.edtage);
				EditText job = (EditText) findViewById(R.id.edtjob);

				SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME);
				try{
					request.addProperty("id", Integer.parseInt(id.getText().toString()));
					request.addProperty("firstname", fname.getText().toString());
					request.addProperty("lastname", lname.getText().toString());
					request.addProperty("age", Integer.parseInt(age.getText().toString()));
					request.addProperty("jobs", job.getText().toString());
					SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(
							SoapEnvelope.VER11);
					envelope.dotNet = true;
					envelope.setOutputSoapObject(request);

					HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);

					try {

						androidHttpTransport.call(SOAP_ACTION, envelope);
						SoapObject result = (SoapObject) envelope.bodyIn;
						SoapPrimitive test = (SoapPrimitive) envelope.getResponse();
						String txt = test.toString();
						if (result != null) {
							Toast.makeText(Add.this, txt, Toast.LENGTH_SHORT)
									.show();
						} else {
							Toast.makeText(Add.this, "Web Service not Response!",
									Toast.LENGTH_SHORT).show();
						}
					} catch (IOException e) {
						e.printStackTrace();
					} catch (XmlPullParserException e) {
						e.printStackTrace();
					} catch (Exception e) {
						e.printStackTrace();
					}
				} catch (NumberFormatException e) {
					Toast.makeText(Add.this, "ID or Age Error",
							Toast.LENGTH_SHORT).show();
					e.printStackTrace();
				}	
			}
		});