org.eclipse.swt.printing
Class Printer

java.lang.Object
  extended by org.eclipse.swt.graphics.Device
      extended by org.eclipse.swt.printing.Printer
All Implemented Interfaces:
Drawable

public final class Printer
extends Device

Instances of this class are used to print to a printer. Applications create a GC on a printer using new GC(printer) and then draw on the printer GC using the usual graphics calls.

A Printer object may be constructed by providing a PrinterData object which identifies the printer. A PrintDialog presents a print dialog to the user and returns an initialized instance of PrinterData. Alternatively, calling new Printer() will construct a printer object for the user's default printer.

Application code must explicitly invoke the Printer.dispose() method to release the operating system resources managed by each instance when those instances are no longer required.

See Also:
PrinterData, PrintDialog, Printing snippets, Sample code and further information

Field Summary
 
Fields inherited from class org.eclipse.swt.graphics.Device
CurrentDevice, DEBUG, DeviceFinder, xDisplay
 
Constructor Summary
Printer()
          Constructs a new printer representing the default printer.
Printer(PrinterData data)
          Constructs a new printer given a PrinterData object representing the desired printer.
 
Method Summary
 void cancelJob()
          Cancels a print job in progress.
 Rectangle computeTrim(int x, int y, int width, int height)
          Given a client area (as described by the arguments), returns a rectangle, relative to the client area's coordinates, that is the client area expanded by the printer's trim (or minimum margins).
protected  void create(DeviceData deviceData)
          Creates the printer handle.
protected  void destroy()
          Destroys the printer handle.
 void endJob()
          Ends the current print job.
 void endPage()
          Ends the current page.
 Rectangle getBounds()
          Returns a rectangle describing the receiver's size and location.
 Rectangle getClientArea()
          Returns a rectangle which describes the area of the receiver which is capable of displaying data.
static PrinterData getDefaultPrinterData()
          Returns a PrinterData object representing the default printer or null if there is no printer available on the System.
 Point getDPI()
          Returns a point whose x coordinate is the horizontal dots per inch of the printer, and whose y coordinate is the vertical dots per inch of the printer.
 PrinterData getPrinterData()
          Returns a PrinterData object representing the target printer for this print job.
static PrinterData[] getPrinterList()
          Returns an array of PrinterData objects representing all available printers.
 Font getSystemFont()
          Returns a reasonable font for applications to use.
protected  void init()
          Initializes any internal resources needed by the device.
 void internal_dispose_GC(long gdkGC, GCData data)
          Invokes platform specific functionality to dispose a GC handle.
 long internal_new_GC(GCData data)
          Invokes platform specific functionality to allocate a new GC handle.
protected  void release()
          Releases any internal state prior to destroying this printer.
 boolean startJob(java.lang.String jobName)
          Starts a print job and returns true if the job started successfully and false otherwise.
 boolean startPage()
          Starts a page and returns true if the page started successfully and false otherwise.
 
Methods inherited from class org.eclipse.swt.graphics.Device
checkDevice, dispose, getDepth, getDeviceData, getFontList, getSystemColor, getWarnings, isDisposed, loadFont, setWarnings
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Printer

public Printer()
Constructs a new printer representing the default printer.

You must dispose the printer when it is no longer required.

Throws:
SWTError -
  • ERROR_NO_HANDLES - if there are no valid printers
See Also:
Device.dispose()

Printer

public Printer(PrinterData data)
Constructs a new printer given a PrinterData object representing the desired printer.

You must dispose the printer when it is no longer required.

Parameters:
data - the printer data for the specified printer
Throws:
java.lang.IllegalArgumentException -
  • ERROR_INVALID_ARGUMENT - if the specified printer data does not represent a valid printer
SWTError -
  • ERROR_NO_HANDLES - if there are no valid printers
See Also:
Device.dispose()
Method Detail

getPrinterList

public static PrinterData[] getPrinterList()
Returns an array of PrinterData objects representing all available printers.

Returns:
the list of available printers

getDefaultPrinterData

public static PrinterData getDefaultPrinterData()
Returns a PrinterData object representing the default printer or null if there is no printer available on the System.

Returns:
the default printer data or null
Since:
2.1

getSystemFont

public Font getSystemFont()
Returns a reasonable font for applications to use. On some platforms, this will match the "default font" or "system font" if such can be found. This font should not be free'd because it was allocated by the system, not the application.

Typically, applications which want the default look should simply not set the font on the widgets they create. Widgets are always created with the correct default font for the class of user-interface component they represent.

Overrides:
getSystemFont in class Device
Returns:
a font
Throws:
SWTException -
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
  • ERROR_DEVICE_DISPOSED - if the receiver has been disposed

internal_new_GC

public long internal_new_GC(GCData data)
Invokes platform specific functionality to allocate a new GC handle.

IMPORTANT: This method is not part of the public API for Printer. It is marked public only so that it can be shared within the packages provided by SWT. It is not available on all platforms, and should never be called from application code.

Specified by:
internal_new_GC in interface Drawable
Specified by:
internal_new_GC in class Device
Parameters:
data - the platform specific GC data
Returns:
the platform specific GC handle

internal_dispose_GC

public void internal_dispose_GC(long gdkGC,
                                GCData data)
Invokes platform specific functionality to dispose a GC handle.

IMPORTANT: This method is not part of the public API for Printer. It is marked public only so that it can be shared within the packages provided by SWT. It is not available on all platforms, and should never be called from application code.

Specified by:
internal_dispose_GC in interface Drawable
Specified by:
internal_dispose_GC in class Device
Parameters:
hDC - the platform specific GC handle
data - the platform specific GC data

release

protected void release()
Releases any internal state prior to destroying this printer. This method is called internally by the dispose mechanism of the Device class.

Overrides:
release in class Device
See Also:
Device.dispose(), Device.destroy()

startJob

public boolean startJob(java.lang.String jobName)
Starts a print job and returns true if the job started successfully and false otherwise.

This must be the first method called to initiate a print job, followed by any number of startPage/endPage calls, followed by endJob. Calling startPage, endPage, or endJob before startJob will result in undefined behavior.

Parameters:
jobName - the name of the print job to start
Returns:
true if the job started successfully and false otherwise.
Throws:
SWTException -
  • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
See Also:
startPage(), endPage(), endJob()

destroy

protected void destroy()
Destroys the printer handle. This method is called internally by the dispose mechanism of the Device class.

Overrides:
destroy in class Device
See Also:
Device.dispose(), Device.release()

endJob

public void endJob()
Ends the current print job.

Throws:
SWTException -
  • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
See Also:
startJob(java.lang.String), startPage(), endPage()

cancelJob

public void cancelJob()
Cancels a print job in progress.

Throws:
SWTException -
  • ERROR_DEVICE_DISPOSED - if the receiver has been disposed

startPage

public boolean startPage()
Starts a page and returns true if the page started successfully and false otherwise.

After calling startJob, this method may be called any number of times along with a matching endPage.

Returns:
true if the page started successfully and false otherwise.
Throws:
SWTException -
  • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
See Also:
endPage(), startJob(java.lang.String), endJob()

endPage

public void endPage()
Ends the current page.

Throws:
SWTException -
  • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
See Also:
startPage(), startJob(java.lang.String), endJob()

getDPI

public Point getDPI()
Returns a point whose x coordinate is the horizontal dots per inch of the printer, and whose y coordinate is the vertical dots per inch of the printer.

Overrides:
getDPI in class Device
Returns:
the horizontal and vertical DPI
Throws:
SWTException -
  • ERROR_DEVICE_DISPOSED - if the receiver has been disposed

getBounds

public Rectangle getBounds()
Returns a rectangle describing the receiver's size and location.

For a printer, this is the size of the physical page, in pixels.

Overrides:
getBounds in class Device
Returns:
the bounding rectangle
Throws:
SWTException -
  • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
See Also:
getClientArea(), computeTrim(int, int, int, int)

getClientArea

public Rectangle getClientArea()
Returns a rectangle which describes the area of the receiver which is capable of displaying data.

For a printer, this is the size of the printable area of the page, in pixels.

Overrides:
getClientArea in class Device
Returns:
the client area
Throws:
SWTException -
  • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
See Also:
getBounds(), computeTrim(int, int, int, int)

computeTrim

public Rectangle computeTrim(int x,
                             int y,
                             int width,
                             int height)
Given a client area (as described by the arguments), returns a rectangle, relative to the client area's coordinates, that is the client area expanded by the printer's trim (or minimum margins).

Most printers have a minimum margin on each edge of the paper where the printer device is unable to print. This margin is known as the "trim." This method can be used to calculate the printer's minimum margins by passing in a client area of 0, 0, 0, 0 and then using the resulting x and y coordinates (which will be <= 0) to determine the minimum margins for the top and left edges of the paper, and the resulting width and height (offset by the resulting x and y) to determine the minimum margins for the bottom and right edges of the paper, as follows:

Parameters:
x - the x coordinate of the client area
y - the y coordinate of the client area
width - the width of the client area
height - the height of the client area
Returns:
a rectangle, relative to the client area's coordinates, that is the client area expanded by the printer's trim (or minimum margins)
Throws:
SWTException -
  • ERROR_DEVICE_DISPOSED - if the receiver has been disposed
See Also:
getBounds(), getClientArea()

create

protected void create(DeviceData deviceData)
Creates the printer handle. This method is called internally by the instance creation mechanism of the Device class.

Overrides:
create in class Device
Parameters:
deviceData - the device data
See Also:
Device.init()

init

protected void init()
Initializes any internal resources needed by the device.

This method is called after create.

If subclasses reimplement this method, they must call the super implementation.

Overrides:
init in class Device
See Also:
create(org.eclipse.swt.graphics.DeviceData)

getPrinterData

public PrinterData getPrinterData()
Returns a PrinterData object representing the target printer for this print job.

Returns:
a PrinterData object describing the receiver