java.lang.Object
- ch.ntb.usb.LibusbJava

```
public class LibusbJava
extends java.lang.Object
```
This class represents the Java Native Interface to the shared library which is (with some exceptions) a one-to-one representation of the libusb API.

Project Description
Java libusb is a Java wrapper for the libusb and libusb-win32 USB library. libusb aim is to create a library for use by user level applications to access USB devices regardless of OS.
Libusb-win32 is a port of the USB library libusb to the Windows operating systems. The library allows user space applications to access any USB device on Windows in a generic way without writing any line of kernel driver code.

The API description of this class has been copied from the libusb documentation and adapted where neccessary.

Field Summary

Fields
Modifier and Type	Field	Description
`static int`	`ERROR_BAD_FILE_DESCRIPTOR`	System error codes. This list is not complete! For more error codes see the file 'errorno.h' on your system.
`static int`	`ERROR_BUSY`	System error codes. This list is not complete! For more error codes see the file 'errorno.h' on your system.
`static int`	`ERROR_INVALID_PARAMETER`	System error codes. This list is not complete! For more error codes see the file 'errorno.h' on your system.
`static int`	`ERROR_IO_ERROR`	System error codes. This list is not complete! For more error codes see the file 'errorno.h' on your system.
`static int`	`ERROR_NO_SUCH_DEVICE_OR_ADDRESS`	System error codes. This list is not complete! For more error codes see the file 'errorno.h' on your system.
`static int`	`ERROR_NOT_ENOUGH_MEMORY`	System error codes. This list is not complete! For more error codes see the file 'errorno.h' on your system.
`static int`	`ERROR_SUCCESS`	System error codes. This list is not complete! For more error codes see the file 'errorno.h' on your system.
`static int`	`ERROR_TIMEDOUT`	System error codes. This list is not complete! For more error codes see the file 'errorno.h' on your system.

Constructor Summary

Constructors
Constructor Description

LibusbJava()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static int`	`usb_bulk_read(long dev_handle, int ep, byte[] bytes, int size, int timeout)`	Performs a bulk read request to the endpoint specified by ep.
`static int`	`usb_bulk_write(long dev_handle, int ep, byte[] bytes, int size, int timeout)`	Performs a bulk write request to the endpoint specified by ep.
`static int`	`usb_claim_interface(long dev_handle, int interface_)`	Claim an interface of a device. Must be called!: `usb_claim_interface` must be called before you perform any operations related to this interface (like `usb_set_altinterface, usb_bulk_write`, etc).
`static int`	`usb_clear_halt(long dev_handle, int ep)`	Clears any halt status on an endpoint.
`static int`	`usb_close(long dev_handle)`	`usb_close` closes a device opened with `usb_open`.
`static int`	`usb_control_msg(long dev_handle, int requesttype, int request, int value, int index, byte[] bytes, int size, int timeout)`	Performs a control request to the default control pipe on a device.
`static int`	`usb_find_busses()`	`usb_find_busses` will find all of the busses on the system.
`static int`	`usb_find_devices()`	`usb_find_devices` will find all of the devices on each bus.
`static Usb_Bus`	`usb_get_busses()`	`usb_get_busses` returns a tree of descriptor objects. The tree represents the bus structure with devices, configurations, interfaces and endpoints.
`static java.lang.String`	`usb_get_descriptor(long dev_handle, byte type, byte index, int size)`	Retrieves a descriptor from the device identified by the type and index of the descriptor from the default control pipe. See `usb_get_descriptor_by_endpoint(long, int, byte, byte, int)` for a function that allows the control endpoint to be specified.
`static java.lang.String`	`usb_get_descriptor_by_endpoint(long dev_handle, int ep, byte type, byte index, int size)`	Retrieves a descriptor from the device identified by the type and index of the descriptor from the control pipe identified by ep.
`static java.lang.String`	`usb_get_string(long dev_handle, int index, int langid)`	Retrieves the string descriptor specified by index and langid from a device.
`static java.lang.String`	`usb_get_string_simple(long dev_handle, int index)`	`usb_get_string_simple` is a wrapper around `usb_get_string` that retrieves the string description specified by index in the first language for the descriptor.
`static void`	`usb_init()`	Just like the name implies, `usb_init` sets up some internal structures.
`static int`	`usb_interrupt_read(long dev_handle, int ep, byte[] bytes, int size, int timeout)`	Performs a interrupt read request to the endpoint specified by ep.
`static int`	`usb_interrupt_write(long dev_handle, int ep, byte[] bytes, int size, int timeout)`	Performs an interrupt write request to the endpoint specified by ep.
`static long`	`usb_open(Usb_Device dev)`	`usb_open` is to be used to open up a device for use.
`static int`	`usb_release_interface(long dev_handle, int interface_)`	Releases a previously claimed interface
`static int`	`usb_reset(long dev_handle)`	Resets a device by sending a RESET down the port it is connected to. Causes re-enumeration: After calling `usb_reset`, the device will need to re-enumerate and thusly, requires you to find the new device and open a new handle.
`static int`	`usb_set_altinterface(long dev_handle, int alternate)`	Sets the active alternate setting of the current interface
`static int`	`usb_set_configuration(long dev_handle, int configuration)`	Sets the active configuration of a device
`static void`	`usb_set_debug(int level)`	Sets the debugging level of libusb. The range is from 0 to 255, where 0 disables debug output and 255 enables all output.
`static java.lang.String`	`usb_strerror()`	Returns the error string after an error occured.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - ERROR_SUCCESS
```
public static int ERROR_SUCCESS
```
    System error codes.
    This list is not complete! For more error codes see the file 'errorno.h' on your system.
  - ERROR_BAD_FILE_DESCRIPTOR
```
public static int ERROR_BAD_FILE_DESCRIPTOR
```
    System error codes.
    This list is not complete! For more error codes see the file 'errorno.h' on your system.
  - ERROR_NO_SUCH_DEVICE_OR_ADDRESS
```
public static int ERROR_NO_SUCH_DEVICE_OR_ADDRESS
```
    System error codes.
    This list is not complete! For more error codes see the file 'errorno.h' on your system.
  - ERROR_BUSY
```
public static int ERROR_BUSY
```
    System error codes.
    This list is not complete! For more error codes see the file 'errorno.h' on your system.
  - ERROR_INVALID_PARAMETER
```
public static int ERROR_INVALID_PARAMETER
```
    System error codes.
    This list is not complete! For more error codes see the file 'errorno.h' on your system.
  - ERROR_TIMEDOUT
```
public static int ERROR_TIMEDOUT
```
    System error codes.
    This list is not complete! For more error codes see the file 'errorno.h' on your system.
  - ERROR_IO_ERROR
```
public static int ERROR_IO_ERROR
```
    System error codes.
    This list is not complete! For more error codes see the file 'errorno.h' on your system.
  - ERROR_NOT_ENOUGH_MEMORY
```
public static int ERROR_NOT_ENOUGH_MEMORY
```
    System error codes.
    This list is not complete! For more error codes see the file 'errorno.h' on your system.
- Constructor Detail
  - LibusbJava
```
public LibusbJava()
```
- Method Detail
  - usb_set_debug
```
public static void usb_set_debug(int level)
```
    Sets the debugging level of libusb.
    The range is from 0 to 255, where 0 disables debug output and 255 enables all output. On application start, debugging is disabled (0).
    
    Parameters:
    
    level - 0 to 255
  - usb_init
```
public static void usb_init()
```
    Just like the name implies, usb_init sets up some internal structures. usb_init must be called before any other libusb functions.
  - usb_find_busses
```
public static int usb_find_busses()
```
    usb_find_busses will find all of the busses on the system.
    
    Returns:
    
    the number of changes since previous call to this function (total of new busses and busses removed).
  - usb_find_devices
```
public static int usb_find_devices()
```
    usb_find_devices will find all of the devices on each bus. This should be called after usb_find_busses.
    
    Returns:
    
    the number of changes since the previous call to this function (total of new device and devices removed).
  - usb_get_busses
```
public static Usb_Bus usb_get_busses()
```
    usb_get_busses returns a tree of descriptor objects.
    The tree represents the bus structure with devices, configurations, interfaces and endpoints. Note that this is only a copy. To refresh the information, usb_get_busses() must be called again.
    The name of the objects contained in the tree is starting with Usb_.
    
    Returns:
    
    the structure of all busses and devices. Note: The java objects are copies of the C structs.
  - usb_open
```
public static long usb_open(Usb_Device dev)
```
    usb_open is to be used to open up a device for use. usb_open must be called before attempting to perform any operations to the device.
    
    Parameters:
    
    dev - The device to open.
    
    Returns:
    
    a handle used in future communication with the device. 0 if an error has occurred.
  - usb_close
```
public static int usb_close(long dev_handle)
```
    usb_close closes a device opened with usb_open.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    Returns:
    
    0 on success or < 0 on error.
  - usb_set_configuration
```
public static int usb_set_configuration(long dev_handle,
                                        int configuration)
```
    Sets the active configuration of a device
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    configuration - The value as specified in the descriptor field bConfigurationValue.
    
    Returns:
    
    0 on success or < 0 on error.
  - usb_set_altinterface
```
public static int usb_set_altinterface(long dev_handle,
                                       int alternate)
```
    Sets the active alternate setting of the current interface
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    alternate - The value as specified in the descriptor field bAlternateSetting.
    
    Returns:
    
    0 on success or < 0 on error.
  - usb_clear_halt
```
public static int usb_clear_halt(long dev_handle,
                                 int ep)
```
    Clears any halt status on an endpoint.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    ep - The value specified in the descriptor field bEndpointAddress.
    
    Returns:
    
    0 on success or < 0 on error.
  - usb_reset
```
public static int usb_reset(long dev_handle)
```
    Resets a device by sending a RESET down the port it is connected to.
    
    Causes re-enumeration: After calling usb_reset, the device will need to re-enumerate and thusly, requires you to find the new device and open a new handle. The handle used to call usb_reset will no longer work.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    Returns:
    
    0 on success or < 0 on error.
  - usb_claim_interface
```
public static int usb_claim_interface(long dev_handle,
                                      int interface_)
```
    Claim an interface of a device.
    
    Must be called!: usb_claim_interface must be called before you perform any operations related to this interface (like usb_set_altinterface, usb_bulk_write, etc).
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    interface_ - The value as specified in the descriptor field bInterfaceNumber.
    
    Returns:
    
    0 on success or < 0 on error.
  - usb_release_interface
```
public static int usb_release_interface(long dev_handle,
                                        int interface_)
```
    Releases a previously claimed interface
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    interface_ - The value as specified in the descriptor field bInterfaceNumber.
    
    Returns:
    
    0 on success or < 0 on error.
  - usb_control_msg
```
public static int usb_control_msg(long dev_handle,
                                  int requesttype,
                                  int request,
                                  int value,
                                  int index,
                                  byte[] bytes,
                                  int size,
                                  int timeout)
```
    Performs a control request to the default control pipe on a device. The parameters mirror the types of the same name in the USB specification.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    requesttype -
    
    request -
    
    value -
    
    index -
    
    bytes -
    
    size -
    
    timeout -
    
    Returns:
    
    the number of bytes written/read or < 0 on error.
  - usb_get_string
```
public static java.lang.String usb_get_string(long dev_handle,
                                              int index,
                                              int langid)
```
    Retrieves the string descriptor specified by index and langid from a device.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    index -
    
    langid -
    
    Returns:
    
    the descriptor String or null
  - usb_get_string_simple
```
public static java.lang.String usb_get_string_simple(long dev_handle,
                                                     int index)
```
    usb_get_string_simple is a wrapper around usb_get_string that retrieves the string description specified by index in the first language for the descriptor.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    index -
    
    Returns:
    
    the descriptor String or null
  - usb_get_descriptor
```
public static java.lang.String usb_get_descriptor(long dev_handle,
                                                  byte type,
                                                  byte index,
                                                  int size)
```
    Retrieves a descriptor from the device identified by the type and index of the descriptor from the default control pipe.
    
    See usb_get_descriptor_by_endpoint(long, int, byte, byte, int) for a function that allows the control endpoint to be specified.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    type -
    
    index -
    
    size - number of charactes which will be retrieved (the length of the resulting String)
    
    Returns:
    
    the descriptor String or null
  - usb_get_descriptor_by_endpoint
```
public static java.lang.String usb_get_descriptor_by_endpoint(long dev_handle,
                                                              int ep,
                                                              byte type,
                                                              byte index,
                                                              int size)
```
    Retrieves a descriptor from the device identified by the type and index of the descriptor from the control pipe identified by ep.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    ep -
    
    type -
    
    index -
    
    size - number of charactes which will be retrieved (the length of the resulting String)
    
    Returns:
    
    the descriptor String or null
  - usb_bulk_write
```
public static int usb_bulk_write(long dev_handle,
                                 int ep,
                                 byte[] bytes,
                                 int size,
                                 int timeout)
```
    Performs a bulk write request to the endpoint specified by ep.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    ep -
    
    bytes -
    
    size -
    
    timeout -
    
    Returns:
    
    the number of bytes written on success or < 0 on error.
  - usb_bulk_read
```
public static int usb_bulk_read(long dev_handle,
                                int ep,
                                byte[] bytes,
                                int size,
                                int timeout)
```
    Performs a bulk read request to the endpoint specified by ep.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    ep -
    
    bytes -
    
    size -
    
    timeout -
    
    Returns:
    
    the number of bytes read on success or < 0 on error.
  - usb_interrupt_write
```
public static int usb_interrupt_write(long dev_handle,
                                      int ep,
                                      byte[] bytes,
                                      int size,
                                      int timeout)
```
    Performs an interrupt write request to the endpoint specified by ep.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    ep -
    
    bytes -
    
    size -
    
    timeout -
    
    Returns:
    
    the number of bytes written on success or < 0 on error.
  - usb_interrupt_read
```
public static int usb_interrupt_read(long dev_handle,
                                     int ep,
                                     byte[] bytes,
                                     int size,
                                     int timeout)
```
    Performs a interrupt read request to the endpoint specified by ep.
    
    Parameters:
    
    dev_handle - The handle to the device.
    
    ep -
    
    bytes -
    
    size -
    
    timeout -
    
    Returns:
    
    the number of bytes read on success or < 0 on error.
  - usb_strerror
```
public static java.lang.String usb_strerror()
```
    Returns the error string after an error occured.
    
    Returns:
    
    the last error sring.

Class LibusbJava

Project Description

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

ERROR_SUCCESS

ERROR_BAD_FILE_DESCRIPTOR

ERROR_NO_SUCH_DEVICE_OR_ADDRESS

ERROR_BUSY

ERROR_INVALID_PARAMETER

ERROR_TIMEDOUT

ERROR_IO_ERROR

ERROR_NOT_ENOUGH_MEMORY

Constructor Detail

LibusbJava

Method Detail

usb_set_debug

usb_init

usb_find_busses

usb_find_devices

usb_get_busses

usb_open

usb_close

usb_set_configuration

usb_set_altinterface

usb_clear_halt

usb_reset

usb_claim_interface

usb_release_interface

usb_control_msg

usb_get_string

usb_get_string_simple

usb_get_descriptor

usb_get_descriptor_by_endpoint

usb_bulk_write

usb_bulk_read

usb_interrupt_write

usb_interrupt_read

usb_strerror