Rxtx - User contributions [en]

Discovering available comm ports

Ericmarshall — Wed, 19 Sep 2007 21:01:45 GMT

Ericmarshall: simplified code

This code snippet shows how to iretrive the available comms ports on your computer. A CommPort is available if it is not being used by another application. Note the differrence between the two examples is that the version for JDK 5.0 up uses [http://java.sun.com/j2se/1.5.0/docs/guide/language/generics.html generics]:

<b>JDK <= 1.4</b>
<pre>
/**
* @return A HashSet containing the CommPortIdentifier for all serial ports that are not currently being used.
*/
public static HashSet getAvailableSerialPorts() {
HashSet h = new HashSet();
Enumeration thePorts = CommPortIdentifier.getPortIdentifiers();
while (thePorts.hasMoreElements()) {
CommPortIdentifier com = (CommPortIdentifier) thePorts.nextElement();
switch (com.getPortType()) {
case CommPortIdentifier.PORT_SERIAL:
try {
CommPort thePort = com.open("CommUtil", 50);
thePort.close();
h.add(com);
} catch (PortInUseException e) {
System.out.println("Port, " + com.getName() + ", is in use.");
} catch (Exception e) {
System.err.println("Failed to open port " + com.getName());
e.printStackTrace();
}
}
}
return h;
}
</pre>

<b>JDK >= 5.0</b>
<pre>
/**
* @return A HashSet containing the CommPortIdentifier for all serial ports that are not currently being used.
*/
public static HashSet<CommPortIdentifier> getAvailableSerialPorts() {
HashSet<CommPortIdentifier> h = new HashSet<CommPortIdentifier>();
Enumeration thePorts = CommPortIdentifier.getPortIdentifiers();
while (thePorts.hasMoreElements()) {
CommPortIdentifier com = (CommPortIdentifier) thePorts.nextElement();
switch (com.getPortType()) {
case CommPortIdentifier.PORT_SERIAL:
try {
CommPort thePort = com.open("CommUtil", 50);
thePort.close();
h.add(com);
} catch (PortInUseException e) {
System.out.println("Port, " + com.getName() + ", is in use.");
} catch (Exception e) {
System.err.println("Failed to open port " + com.getName());
e.printStackTrace();
}
}
}
return h;
}
</pre>

Discovering comm ports

Ericmarshall — Wed, 19 Sep 2007 20:52:13 GMT

Ericmarshall: added missing + signs

This code snippet shows how to find out the available comms ports on your computer.:

<pre>
static void listPorts()
{
Enumeration portEnum = CommPortIdentifier.getPortIdentifiers();
while ( portEnum.hasMoreElements() )
{
CommPortIdentifier portIdentifier = (CommPortIdentifier) portEnum.nextElement();
System.out.println(portIdentifier.getName() + " - " + getPortTypeName(portIdentifier.getPortType()) );
}
}

static String getPortTypeName ( int portType )
{
switch ( portType )
{
case CommPortIdentifier.PORT_I2C:
return "I2C";
case CommPortIdentifier.PORT_PARALLEL:
return "Parallel";
case CommPortIdentifier.PORT_RAW:
return "Raw";
case CommPortIdentifier.PORT_RS485:
return "RS485";
case CommPortIdentifier.PORT_SERIAL:
return "Serial";
default:
return "unknown type";
}
}
</pre>

Discovering comm ports

Ericmarshall — Wed, 19 Sep 2007 20:36:19 GMT

Ericmarshall: revert vandalism

This code snippet shows how to find out the available comms ports on your computer.:

<pre>
static void listPorts()
{
Enumeration portEnum = CommPortIdentifier.getPortIdentifiers();
while ( portEnum.hasMoreElements() )
{
CommPortIdentifier portIdentifier = (CommPortIdentifier) portEnum.nextElement();
System.out.println(portIdentifier.getName() " - " getPortTypeName(portIdentifier.getPortType()) );
}
}

static String getPortTypeName ( int portType )
{
switch ( portType )
{
case CommPortIdentifier.PORT_I2C:
return "I2C";
case CommPortIdentifier.PORT_PARALLEL:
return "Parallel";
case CommPortIdentifier.PORT_RAW:
return "Raw";
case CommPortIdentifier.PORT_RS485:
return "RS485";
case CommPortIdentifier.PORT_SERIAL:
return "Serial";
default:
return "unknown type";
}
}
</pre>