com.dalsemi.onewire
Class OneWireAccessProvider

java.lang.Object
  |
  +--com.dalsemi.onewire.OneWireAccessProvider

public class OneWireAccessProvider

extends Object

The OneWireAccessProvider class manages the Dallas Semiconductor adapter class derivatives of DSPortAdapter. An enumeration of all available adapters can be accessed through the member function EnumerateAllAdapters. This enables an application to be adapter independent. There are also facilities to get a system appropriate default adapter/port combination.

Usage

Example 1

Get an instance of the default 1-Wire adapter. The adapter will be ready to use if no exceptions are thrown.

 
  try
  {   
     DSPortAdapter adapter = OneWireAccessProvider.getDefaultAdapter();
        
     System.out.println("Adapter: " + adapter.getAdapterName() + " Port: " + adapter.getPortName());
     
     // use the adapter ...

  }   
  catch(Exception e)
  {
     System.out.println("Default adapter not present: " + e);
  }
  

Example 2

Enumerate through the available adapters and ports.

 
  DSPortAdapter adapter;
  String        port;

  // get the adapters
  for (Enumeration adapter_enum = OneWireAccessProvider.enumerateAllAdapters();
                                  adapter_enum.hasMoreElements(); )
  {
     // cast the enum as a DSPortAdapter
     adapter = ( DSPortAdapter ) adapter_enum.nextElement();

     System.out.print("Adapter: " + adapter.getAdapterName() + " with ports: ");

     // get the ports
     for (Enumeration port_enum = adapter.getPortNames();
             port_enum.hasMoreElements(); )
     {
        // cast the enum as a String
        port = ( String ) port_enum.nextElement();

        System.out.print(port + " ");
     }

     System.out.println();
  }
  

Example 3

Display the default adapter name and port without getting an instance of the adapter.

 
  System.out.println("Default Adapter: " +
                      OneWireAccessProvider.getProperty("onewire.adapter.default"));
  System.out.println("Default Port: " +
                      OneWireAccessProvider.getProperty("onewire.port.default"));
  

Version:

0.00, 30 August 2000

See Also:

DSPortAdapter

Method Summary

static void	clearUseOverridingAdapter() Clears the overriding adapter.
static Enumeration	enumerateAllAdapters() Gets an Enumeration of all 1-Wire adapter types supported.
static DSPortAdapter	getAdapter(String adapterName, String portName) Finds, opens, and verifies the specified adapter on the indicated port.
static DSPortAdapter	getDefaultAdapter() Finds, opens, and verifies the default adapter and port.
static String	getProperty(String propName) Gets the specfied onewire property.
static void	setUseOverridingAdapter(DSPortAdapter adapter) Sets an overriding adapter.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

enumerateAllAdapters

public static Enumeration enumerateAllAdapters()

Gets an Enumeration of all 1-Wire adapter types supported. Using this enumeration with the port enumeration for each adapter, a search can be done to find all available hardware adapters.

Returns:

Enumeration of DSPortAdapters in the system

getAdapter

public static DSPortAdapter getAdapter(String adapterName,
                                       String portName)
                                throws OneWireIOException,
                                       OneWireException

Finds, opens, and verifies the specified adapter on the indicated port.

Parameters:

adapterName - string name of the adapter (match to result of call to getAdapterName() method in DSPortAdapter)

portName - string name of the port used in the method selectPort() in DSPortAdapter

Returns:

DSPortAdapter if adapter present

Throws:

OneWireIOException - when communcation with the adapter fails

OneWireException - when the port or adapter not present

getDefaultAdapter

public static DSPortAdapter getDefaultAdapter()
                                       throws OneWireIOException,
                                              OneWireException

Finds, opens, and verifies the default adapter and port. Looks for the default adapter/port in the following locations:

• Use adapter/port in System.properties for onewire.adapter.default, and onewire.port.default properties tags.
• Use adapter/port from onewire.properties file in current directory or < java.home >/lib/ (Desktop) or /etc/ (TINI)
• Use smart default
  • Desktop
    • First, TMEX default (Win32 only)
    • Second, if TMEX not present, then DS9097U/(first serial port)
  • TINI, TINIExternalAdapter on port serial1

Returns:

DSPortAdapter if default adapter present

Throws:

OneWireIOException - when communcation with the adapter fails

OneWireException - when the port or adapter not present

getProperty

public static String getProperty(String propName)

Gets the specfied onewire property. Looks for the property in the following locations:

• In System.properties
• In onewire.properties file in current directory or < java.home >/lib/ (Desktop) or /etc/ (TINI)
• 'smart' default if property is 'onewire.adapter.default' or 'onewire.port.default'

Parameters:

propName - string name of the property to read

Returns:

String representing the property value or null if it could not be found (onewire.adapter.default and onewire.port.default may return a 'smart' default even if property not present)

setUseOverridingAdapter

public static void setUseOverridingAdapter(DSPortAdapter adapter)

Sets an overriding adapter. This adapter will be returned from getAdapter and getDefaultAdapter despite what was requested.

Parameters:

adapter - adapter to be the override

See Also:

getAdapter(java.lang.String, java.lang.String), getDefaultAdapter(), clearUseOverridingAdapter()

clearUseOverridingAdapter

public static void clearUseOverridingAdapter()

Clears the overriding adapter. The operation of getAdapter and getDefaultAdapter will be returned to normal.

See Also:

getAdapter(java.lang.String, java.lang.String), getDefaultAdapter(), setUseOverridingAdapter(com.dalsemi.onewire.adapter.DSPortAdapter)