如何讀取特定的字符串？

Question

嗨，我正在嘗試制作Java桌面應用程序，其中我正在從java字符串變量中的seril端口接收值，並且正在通過硬件設備接收數據，這將連續拋出數據，我現在將該數據存儲在字符串變量中，我想僅從中獲取一些特定數據。

所以我怎么能做到這一點我正在接收以下格式的數據

$GPRMC,235949.799,V,,,,,0.00,0.00,050180,,,N*46
$GPVTG,0.00,T,,M,0.00,N,0.00,K,N*32
$GPGGA,235949.799,,,,,0,0,,,M,,M,,*4F
$GPGSA,A,1,,,,,,,,,,,,,,,*1E
$GPGSV,1,1,00*79
$GPGLL,,,,,235949.799,V,N*7D
$GPTXT,01,01,02,ANTSTATUS=OPEN*2B

這個字符串不斷收到

我想從這個字符串中獲得每個字符串的僅第一行

這是我的代碼

public class ListPortClass
{
 private int times = 0;



public static void main(String[] s)

{
    BufferedReader br = null;
try
{
     String sCurrentLine;
CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier("COM6");
if (portIdentifier.isCurrentlyOwned())
{
System.out.println("Port in use!");
}
else {
System.out.println(portIdentifier.getName());

SerialPort serialPort = (SerialPort) portIdentifier.open("ListPortClass", 300);
int b = serialPort.getBaudRate();
System.out.println(Integer.toString(b));
serialPort.setSerialPortParams(300, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);
OutputStream mOutputToPort = serialPort.getOutputStream();
InputStream mInputFromPort = serialPort.getInputStream();
String mValue = "DEBUG_GPS";
System.out.println("beginning to Write . \r\n");
mOutputToPort.write(mValue.getBytes());
System.out.println("DEBUG_GPS Command Written to Port. \r\n");
mOutputToPort.flush();
System.out.println("Waiting for Reply \r\n");
Thread.sleep(500);
byte mBytesIn [];// = new byte[48];
//for(int i=0;i<=mBytesIn.length;i++){
mInputFromPort.read(); 
try{
while(true){
int a = mInputFromPort.read();
char c=(char)a;
//String  c =String.valueOf(a);
//System.out.print(c);
String temp = Character.toString(c);
System.out.print(temp);

}}
catch(IOException e)
{System.out.println(e);}

mOutputToPort.close(); 
mInputFromPort.close();
}
}
catch (Exception ex)
{

System.out.println("Exception : " + ex.getMessage());
}
}
}

這是我更新的代碼

public static void main(String[] s)

{
    BufferedReader br = null;
try
{
     String sCurrentLine;
CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier("COM6");
if (portIdentifier.isCurrentlyOwned())
{
System.out.println("Port in use!");
}
else {
System.out.println(portIdentifier.getName());

SerialPort serialPort = (SerialPort) portIdentifier.open("ListPortClass", 300);
int b = serialPort.getBaudRate();
System.out.println(Integer.toString(b));
serialPort.setSerialPortParams(300, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);
OutputStream mOutputToPort = serialPort.getOutputStream();
InputStream mInputFromPort = serialPort.getInputStream();
String mValue = "DEBUG_GPS";
System.out.println("beginning to Write . \r\n");
mOutputToPort.write(mValue.getBytes());
System.out.println("DEBUG_GPS Command Written to Port. \r\n");
mOutputToPort.flush();
System.out.println("Waiting for Reply \r\n");
Thread.sleep(500);

try {

            br = new BufferedReader (new InputStreamReader(mInputFromPort));
            while ((sCurrentLine = br.readLine()) != null) {
                System.out.println(sCurrentLine);
            }
}
catch(IOException e){
    e.printStackTrace();
}

//mOutputToPort.close(); 
//mInputFromPort.close();
}
}
catch (Exception ex)
{

System.out.println("Exception : " + ex.getMessage());
}
}
}

我沒有按照以下代碼更新代碼

Answer 1

您已經在代碼中定義了一個BufferedReader對象，但尚未使用。 如果使用，則可以使用readLine方法。 每次成功讀取一行后，您都可以將其發送到另一種方法進行處理。

將您的BufferedReader構造為

br = new BufferedReader(new InputStreamReader(mInputFromPort));

你想要的是

//for(int i=0;i<=mBytesIn.length;i++){

// CUT ALL OF THIS CODE

// until here 
try {

        br = new BufferedReader (new InputStreamReader(mInputFromPort));
        while ((sCurrentLine = br.readLine()) != null) {
            System.out.println(sCurrentLine);
        }
} catch(IOException e){
e.printStackTrace();
}

你不想做mInputFromPort.read(); 東西，您現在將要使用readLine代碼，而不是兩者都使用