1
I have a java code in which you receive engine speed data. In java with I get a String I need to convert to integer to make a comparison to know if the engine started or not. When I get the string I print on the screen and it correctly appears the value, but in the dialog for the integer it only receives the value null, because the String is correct but when it converts me rtorna null, it has another way of conversation?
Follow the code:
package tanio;
import javax.swing.SwingWorker;
public class obterrpm extends SwingWorker {
public SerialVirtualCom3 arduino6;
String valorrpm;
int valorrpmint;
protected Object doInBackground() throws Exception {
SerialVirtualCom3 arduino6 = new SerialVirtualCom3("COM3", 9600,0);
arduino6.receberDados();
while(true){
delay.delay(300);
valorrpm = arduino6.getPeso();
//System.out.println(valorrpm); //printa o valor corretamente
valorrpmint = Integer.parseInt(valorrpm); //conversao para o int
System.out.println(valorrpmint); //retorno e null
//chamarTelaPrincipal.rpm.setText(String.format("%s",arduino6.getPeso()));
//chamarTelaPrincipal.rpm.setText(String.format("%s", valorrpmint));
}
}
}
Serialvirtualcom3
package tanio;
import gnu.io.CommPortIdentifier;
import gnu.io.NoSuchPortException;
import gnu.io.SerialPort;
import gnu.io.SerialPortEvent;
import gnu.io.SerialPortEventListener;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.Iterator;
import javax.swing.JOptionPane;
import javax.swing.SwingWorker;
public class SerialVirtualCom3 implements Runnable, SerialPortEventListener {
public String Dadoslidos;
public int nodeBytes;
private int baudrate;
private int timeout;
private CommPortIdentifier cp;
private SerialPort porta;
private OutputStream saida;
private InputStream entrada;
private Thread threadLeitura;
private boolean IDPortaOK;
private boolean PortaOK;
private boolean Leitura;
private boolean Escrita;
private String Porta;
protected String peso;
public char valorlido;
public void setPeso(String peso){
this.peso = peso;
}
public String getPeso(){
return peso;
}
public SerialVirtualCom3( String p , int b , int t ){
this.Porta = p;
this.baudrate = b;
this.timeout = t;
}
public void HabilitarEscrita(){
Escrita = true;
Leitura = false;
}
public void HabilitarLeitura(){
Escrita = false;
Leitura = true;
}
///////////////////////////////////////////////////////
///*
public void ObterIdDaPorta(){
try {
cp = CommPortIdentifier.getPortIdentifier(Porta);
if ( cp != null ) {
// System.out.println("Sucesso");
IDPortaOK = true;
// ligado = 0;
// desligado = 1;
}
}
/*
IDPortaOK = false;
ligado = 1;
desligado = 0;
//ligado = 1;
//desligado = 0
}
*/
catch (NoSuchPortException e) {
e.printStackTrace();
//System.out.println("Nao ha Conexao!");
// JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
//teste de tratamento desta excessao
//ligado = 1;
//desligado = 0;
//ObterIdDaPorta();
//IDPortaOK = false;
}
}
//*/
//////////////////////////////////////////////////////
/*
public void ObterIdDaPorta(){
boolean flag = false;
// while (flag == false ){
try {
cp = CommPortIdentifier.getPortIdentifier(Porta);
if ( cp == null ) {
System.out.println("Erro na porta");
IDPortaOK = false;
JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
// FecharCom();
//ObterIdDaPorta();
//System.exit(1);
}
IDPortaOK = true;
// flag = true;
} catch (Exception e) {
e.printStackTrace();
//System.out.println("Erro obtendo ID da porta: " + e);
JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
//JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!");
IDPortaOK = false;
//FecharCom();
//flag = false;
//ObterIdDaPorta();
//System.exit(1);
}
}
// }
//}
//}
*/
/*
public void AbrirPorta(){
try {
porta = (SerialPort)cp.open("SerialComLeitura", timeout);
PortaOK = true;
//configurar parâmetros
porta.setSerialPortParams(baudrate,
porta.DATABITS_8,
porta.STOPBITS_1,
porta.PARITY_NONE);
porta.setFlowControlMode(SerialPort.FLOWCONTROL_NONE);
}catch(Exception e){
e.printStackTrace();
//PortaOK = false;
//System.out.println("Erro abrindo comunicação: " + e);
JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
FecharCom();
//System.exit(1);
}
}
*/
public void AbrirPorta(){
try {
porta = (SerialPort)cp.open("SerialComLeitura", timeout);
if (porta != null) {
//configurar parâmetros
porta.setSerialPortParams(baudrate,
porta.DATABITS_8,
porta.STOPBITS_1,
porta.PARITY_NONE);
porta.setFlowControlMode(SerialPort.FLOWCONTROL_NONE);
// System.out.println("Sucesso no tratamento do erro de abrir porta!");
PortaOK = true;
}
}
catch(Exception e){
e.printStackTrace();
//System.out.println("houve um erro ao tratar a excessao do abrir porta!");
//JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
//teste de tratamento desta excessao
//ligado = 1;
//desligado = 0;
//FecharCom();
//ObterIdDaPorta();
//AbrirPorta();
//ObterIdDaPorta();
//AbrirPorta();
//IDPortaOK = false;
/*
e.printStackTrace();
//PortaOK = false;
//System.out.println("Erro abrindo comunicação: " + e);
JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
FecharCom();
*/
//System.exit(1);
}
}
public void LerDados(){
if (Escrita == false){
try {
entrada = porta.getInputStream();
} catch (Exception e) {
e.printStackTrace();
//System.out.println("Erro de stream: " + e);
//JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
//FecharCom();
//AbrirPorta();
//LerDados();
// System.exit(1);
}
try {
porta.addEventListener(this);
} catch (Exception e) {
e.printStackTrace();
//System.out.println("Erro de listener: " + e);
//JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
//FecharCom();
// AbrirPorta();
// LerDados();
//System.exit(1);
}
porta.notifyOnDataAvailable(true);
try {
threadLeitura = new Thread(this);
threadLeitura.start();
run();
} catch (Exception e) {
e.printStackTrace();
//System.out.println("Erro de Thred: " + e);
// JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
// FecharCom();
//AbrirPorta();
//LerDados();
}
}
}
public void escrever(int msg){
if (Escrita==true) {
try {
saida = porta.getOutputStream();
//System.out.println("FLUXO OK!");
} catch (Exception e) {
e.printStackTrace();
System.out.println("Erro.STATUS: " + e );
//JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!\nReconecte o Cabo e Aguarde alguns segundos!");
//FecharCom();
//enviarDados(msg);
}
try {
//System.out.println("Enviando um byte para " + Porta );
//System.out.println("Enviando : " + msg );
saida.write(msg);
Thread.sleep(100);
saida.flush();
} catch (Exception e) {
e.printStackTrace();
//System.out.println("Houve um erro durante o envio. ");
System.out.println("STATUS: " + e );
//JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
//FecharCom();
//System.exit(1);
}
} else {
// System.exit(1);
//JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
//FecharCom();
}
}
public void run(){
try {
Thread.sleep(5);
} catch (Exception e) {
e.printStackTrace();
//System.out.println("Erro de Thred: " + e);
//JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
//FecharCom();
//run();
}
}
public void serialEvent(SerialPortEvent ev){
StringBuffer bufferLeitura = new StringBuffer();
int novoDado = 0;
switch (ev.getEventType()) {
case SerialPortEvent.BI:
case SerialPortEvent.OE:
case SerialPortEvent.FE:
case SerialPortEvent.PE:
case SerialPortEvent.CD:
case SerialPortEvent.CTS:
case SerialPortEvent.DSR:
case SerialPortEvent.RI:
case SerialPortEvent.OUTPUT_BUFFER_EMPTY:
break;
case SerialPortEvent.DATA_AVAILABLE:
//Novo algoritmo de leitura.
while(novoDado != -1){
try{
novoDado = entrada.read();
if(novoDado == -1){
break;
}
if('\r' == (char)novoDado){
bufferLeitura.append('\n');
}else{
bufferLeitura.append((char)novoDado);
}
}catch(IOException ioe){
// System.out.println("Erro de leitura serial: " + ioe);
// JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
}
}
setPeso(new String(bufferLeitura));
//System.out.println(getPeso());
break;
}
}
public void FecharCom(){
try {
porta.close();
} catch (Exception e) {
e.printStackTrace();
// System.out.println("Erro fechando porta: " + e);
// JOptionPane.showMessageDialog(null, "Houve um erro na Conexão!\nVerifique o cabo usb!");
// FecharCom();
// System.exit(0);
}
}
public String obterPorta(){
return Porta;
}
public int obterBaudrate(){
return baudrate;
}
public void enviarDados(int msg)
{
HabilitarEscrita();
ObterIdDaPorta();
AbrirPorta();
escrever(msg);
FecharCom();
}
String receberDados(){
HabilitarLeitura();
ObterIdDaPorta();
AbrirPorta();
LerDados();
return getPeso();
}
}
It is not possible that the
System.out.println(valorrpmint);shownull. You can post your exit to take a look at it?– Victor Stafusa
Victor, sorry, with null I meant that it does not return anything, the program runs but not the return if I use valorrpmint. with the variable without conversation, arduino6.getPeso(which is a string) the value is printed on the screen normally. Why will the empty result?
– Aislan Silva Costa
It shows zero?
– Victor Stafusa
No, nothing, in the normal output, with the variable value rpm, the value of the rpm is printed on the screen correctly, However with the value rpmint does not appear anything, it is only in this: WARNING: RXTX Version Mismatch Jar version = RXTX-2.2pre1 Native lib Version = RXTX-2.2pre2
– Aislan Silva Costa
Send us what your copy is showing. Give us a print (value) and send it to us.
– cpll
Try moving the declaration from
valorrpmandvalorrpmintwithin the scope of the methoddoInBackground. Once done, to make sure that the integers and the string in question are matching print the following:System.out.printf("%s - String: %s, int: %d\n", Thread.currentThread().getName(), valorrpm, valorrpmint);.– Anthony Accioly
If I put the two variable statements together in while one disturbs the other, for example, if I put value = arduino6.getPeso(); valorromint = Integer.parseint(valorrpm) nor the variable printa more
– Aislan Silva Costa
The same thing happened Anthony, I played for a thread and gave the following error: WARNING: RXTX Version Mismatch Jar version = RXTX-2.2pre1 Native lib Version = RXTX-2.2pre2 Exception in thread "Thread-0" java.lang.Numberformatexception: For input string: "750 " at java.lang.Numberformatexception.forInputString(Numberformatexception.java:65) at java.lang.Integer.parseint(Integer.java:580) at java.lang.Integer.parseint(Integer.java:615) at Tanio.RunObterRpm.run(Runobtenrpm.java:20) at java.lang.Thread.run(Thread.java:748) //It correctly receives the input value String
– Aislan Silva Costa
But can’t make conversation? Will it be why? need to convert to compare the rpm value to know if the engine started, if (value rpmint > 0 ){car started}Else{car not started}, have cmo make this comparison without converting?
– Aislan Silva Costa
"750 ". Looks like there’s a blank spot at the end of yourString. Try to useInteger.parseInt(valorrpm.trim());If it works, I’ll turn it into an answer.– Anthony Accioly
Anthony, I tried but gave Exception in thread "Thread-0" java.lang.Nullpointerexception at Tanio.RunObterRpm.run(Runobtenrpm.java:20) at java.lang.Thread.run(Thread.java:748)?
– Aislan Silva Costa
You could include the class code
SerialVirtualCom3?– Weslley Tavares
Weslley ta ai, disregard some parts that are among the /*, I was trying to treat the excesses but ended up giving up
– Aislan Silva Costa
Try setting your variable
pesoin a new String. Something likeString str = arduino6.getPeso();. After that, throw thestrin output.– Weslley Tavares
But that’s not what I’m already doing with String valorrpm = arduino6.getPeso(); I don’t mean because this conversation doesn’t work, or when it looks like it will work from the excesses. I’m thinking I should then have to in the buffer read method to return me the integer instead of the string
– Aislan Silva Costa