org.ghost4j

Interface GhostscriptLibrary

All Superinterfaces:

com.sun.jna.Library

public interface GhostscriptLibrary
extends com.sun.jna.Library

Interface (JNA) bridging Ghostscript API (C language) with Java. All API methods are bridged except for: gsapi_set_poll and gsapi_set_visual_tracer. Note: in this interface variable names are kept unchanged compared with the C API. Ghostscript API documentation can be found here: http://ghostscript.com/doc/8.54/API.htm

Author:

Gilles Grousset (gi.grousset@gmail.com)

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	GhostscriptLibrary.display_callback_s Structure defining display callback functions.
static class	GhostscriptLibrary.gs_main_instance Pointer holding a native Ghostscript instance.
static class	GhostscriptLibrary.gsapi_revision_s Structure in charge of holding Ghostscript revision data.
static interface	GhostscriptLibrary.stderr_fn Callback called to provide a custom error output to Ghostscript. str holds output characters. len is the length for str.
static interface	GhostscriptLibrary.stdin_fn Callback called to provide a custom input to Ghostscript. buf is a pointer to a char array. len is the length of the char array.
static interface	GhostscriptLibrary.stdout_fn Callback called to provide a custom output to Ghostscript.

Nested classes/interfaces inherited from interface com.sun.jna.Library

com.sun.jna.Library.Handler

Field Summary

Fields

Modifier and Type	Field and Description
static GhostscriptLibrary	instance Static instance of the library itself.

Fields inherited from interface com.sun.jna.Library

OPTION_ALLOW_OBJECTS, OPTION_CALLING_CONVENTION, OPTION_CLASSLOADER, OPTION_FUNCTION_MAPPER, OPTION_INVOCATION_MAPPER, OPTION_OPEN_FLAGS, OPTION_STRING_ENCODING, OPTION_STRUCTURE_ALIGNMENT, OPTION_TYPE_MAPPER

Method Summary

Methods

Modifier and Type	Method and Description
void	gsapi_delete_instance(com.sun.jna.Pointer instance) Destroy an instance of Ghostscript.
int	gsapi_exit(com.sun.jna.Pointer instance) Exit the interpreter.
int	gsapi_init_with_args(com.sun.jna.Pointer instance, int argc, String[] argv) Initialise the interpreter.
int	gsapi_new_instance(com.sun.jna.Pointer pinstance, com.sun.jna.Pointer caller_handle) Create a new instance of Ghostscript.
int	gsapi_revision(com.sun.jna.Structure pr, int len) This function returns the revision numbers and strings of the Ghostscript interpreter library.
int	gsapi_run_file(com.sun.jna.Pointer instance, String file_name, int user_errors, com.sun.jna.ptr.IntByReference pexit_code) Send instructions from a file to the Ghostscript interpreter.
int	gsapi_run_string_begin(com.sun.jna.Pointer instance, int user_errors, com.sun.jna.ptr.IntByReference pexit_code) Open an instruction block to the Ghostscript interpreter.
int	gsapi_run_string_continue(com.sun.jna.Pointer instance, String str, int length, int user_errors, com.sun.jna.ptr.IntByReference pexit_code) Send instruction to the Ghostscript interpreter.
int	gsapi_run_string_end(com.sun.jna.Pointer instance, int user_errors, com.sun.jna.ptr.IntByReference pexit_code) Close an instruction block to the Ghostscript interpreter.
int	gsapi_run_string_with_length(com.sun.jna.Pointer instance, String str, int length, int user_errors, com.sun.jna.ptr.IntByReference pexit_code) Send instruction to the Ghostscript interpreter.
int	gsapi_run_string(com.sun.jna.Pointer instance, String str, int user_errors, com.sun.jna.ptr.IntByReference pexit_code) Send instruction to the Ghostscript interpreter.
int	gsapi_set_display_callback(com.sun.jna.Pointer instance, com.sun.jna.Structure callback) Set the callback structure for the display device.
int	gsapi_set_stdio(com.sun.jna.Pointer instance, GhostscriptLibrary.stdin_fn stdin_fn, GhostscriptLibrary.stdout_fn stdout_fn, GhostscriptLibrary.stderr_fn stderr_fn) Set the callback functions for stdio.

Field Detail

instance

static final GhostscriptLibrary instance

Static instance of the library itself.

Method Detail

gsapi_revision

int gsapi_revision(com.sun.jna.Structure pr,
                 int len)

This function returns the revision numbers and strings of the Ghostscript interpreter library. You should call it before any other interpreter library functions to make sure that the correct version of the Ghostscript interpreter has been loaded.

Parameters:

pr - Pointer to the gsapi_revision_s that will hold return values.

len - pr Length

Returns:

0 if everything is OK, < 0 otherwise

See Also:

GhostscriptLibrary.gsapi_revision_s

gsapi_new_instance

int gsapi_new_instance(com.sun.jna.Pointer pinstance,
                     com.sun.jna.Pointer caller_handle)

Create a new instance of Ghostscript. This instance is passed to most other gsapi functions. The caller_handle will be provided to callback functions. At this stage, Ghostscript supports only one instance.

Parameters:

pinstance - Pointer to gs_main_instance that will hold the Ghostscript instance.

caller_handle - Caller handler pointer (may be null).

Returns:

0 if everything is OK, < 0 otherwise

gsapi_delete_instance

void gsapi_delete_instance(com.sun.jna.Pointer instance)

Destroy an instance of Ghostscript. Before you call this, Ghostscript must have finished. If Ghostscript has been initialised, you must call gsapi_exit before gsapi_delete_instance.

Parameters:

instance - Pointer to the Ghostscript instance.

gsapi_exit

int gsapi_exit(com.sun.jna.Pointer instance)

Exit the interpreter. This must be called on shutdown if gsapi_init_with_args() has been called, and just before gsapi_delete_instance().

Parameters:

instance - Pointer to the Ghostscript instance.

Returns:

0 if everything is OK, < 0 otherwise

gsapi_init_with_args

int gsapi_init_with_args(com.sun.jna.Pointer instance,
                       int argc,
                       String[] argv)

Initialise the interpreter. This calls gs_main_init_with_args() in imainarg.c. The arguments are the same as the "C" main function: argv[0] is ignored and the user supplied arguments are argv[1] to argv[argc-1].

Parameters:

instance - Pointer to the Ghostscript instance.

argc - Argument count

argv - Argument array

Returns:

0 if everything is OK, < 0 otherwise

gsapi_run_string

int gsapi_run_string(com.sun.jna.Pointer instance,
                   String str,
                   int user_errors,
                   com.sun.jna.ptr.IntByReference pexit_code)

Send instruction to the Ghostscript interpreter. The address passed in pexit_code will be used to return the exit code for the interpreter in case of a quit or fatal error.

Parameters:

instance - Pointer to the Ghostscript instance.

str - Instructions. Max length for the string is 65535.

user_errors - If set to 0 errors are returned the normal way (to the interpreter output), if a negative value is used errors are returns directly by the function.

pexit_code - Pointer to the exit return code

Returns:

0 if everything is OK, < 0 otherwise

gsapi_run_string_with_length

int gsapi_run_string_with_length(com.sun.jna.Pointer instance,
                               String str,
                               int length,
                               int user_errors,
                               com.sun.jna.ptr.IntByReference pexit_code)

Send instruction to the Ghostscript interpreter. The address passed in pexit_code will be used to return the exit code for the interpreter in case of a quit or fatal error.

Parameters:

instance - Pointer to the Ghostscript instance.

str - Instructions. Max length for the string is 65535.

length - str length.

user_errors - If set to 0 errors are returned the normal way (to the interpreter output), if a negative value is used errors are returns directly by the function.

pexit_code - Pointer to the exit return code

Returns:

0 if everything is OK, < 0 otherwise

gsapi_run_string_begin

int gsapi_run_string_begin(com.sun.jna.Pointer instance,
                         int user_errors,
                         com.sun.jna.ptr.IntByReference pexit_code)

Open an instruction block to the Ghostscript interpreter. The address passed in pexit_code will be used to return the exit code for the interpreter in case of a quit or fatal error.

Parameters:

instance - Pointer to the Ghostscript instance.

user_errors - If set to 0 errors are returned the normal way (to the interpreter output), if a negative value is used errors are returns directly by the function.

pexit_code - Pointer to the exit return code

Returns:

0 if everything is OK, < 0 otherwise

gsapi_run_string_continue

int gsapi_run_string_continue(com.sun.jna.Pointer instance,
                            String str,
                            int length,
                            int user_errors,
                            com.sun.jna.ptr.IntByReference pexit_code)

Send instruction to the Ghostscript interpreter. Must be used after gsapi_run_string_begin is called. The address passed in pexit_code will be used to return the exit code for the interpreter in case of a quit or fatal error.

Parameters:

instance - Pointer to the Ghostscript instance.

str - Instructions. Max length for the string is 65535.

length - str length.

user_errors - If set to 0 errors are returned the normal way (to the interpreter output), if a negative value is used errors are returns directly by the function.

pexit_code - Pointer to the exit return code

Returns:

0 if everything is OK, < 0 otherwise

gsapi_run_string_end

int gsapi_run_string_end(com.sun.jna.Pointer instance,
                       int user_errors,
                       com.sun.jna.ptr.IntByReference pexit_code)

Close an instruction block to the Ghostscript interpreter. The address passed in pexit_code will be used to return the exit code for the interpreter in case of a quit or fatal error.

Parameters:

instance - Pointer to the Ghostscript instance.

user_errors - If set to 0 errors are returned the normal way (to the interpreter output), if a negative value is used errors are returns directly by the function.

pexit_code - Pointer to the exit return code

Returns:

0 if everything is OK, < 0 otherwise

gsapi_run_file

int gsapi_run_file(com.sun.jna.Pointer instance,
                 String file_name,
                 int user_errors,
                 com.sun.jna.ptr.IntByReference pexit_code)

Send instructions from a file to the Ghostscript interpreter.

Parameters:

instance - Pointer to the Ghostscript instance.

file_name - File name.

user_errors - If set to 0 errors are returned the normal way (to the interpreter output), if a negative value is used errors are returns directly by the function.

pexit_code -

Returns:

0 if everything is OK, < 0 otherwise

gsapi_set_stdio

int gsapi_set_stdio(com.sun.jna.Pointer instance,
                  GhostscriptLibrary.stdin_fn stdin_fn,
                  GhostscriptLibrary.stdout_fn stdout_fn,
                  GhostscriptLibrary.stderr_fn stderr_fn)

Set the callback functions for stdio. The stdin callback function should return the number of characters read, 0 for EOF, or -1 for error. The stdout and stderr callback functions should return the number of characters written.

Parameters:

instance - Pointer to the Ghostscript instance.

stdin_fn - Stdin callback function.

stdout_fn - Stdout callback function.

stderr_fn - Stderr callback function.

Returns:

0 if everything is OK, < 0 otherwise

gsapi_set_display_callback

int gsapi_set_display_callback(com.sun.jna.Pointer instance,
                             com.sun.jna.Structure callback)

Set the callback structure for the display device. If the display device is used, this must be called after gsapi_new_instance() and before gsapi_init_with_args(). See gdevdsp.h for more details.

Parameters:

instance - Pointer to the Ghostscript instance.

callback - display_callback_s Structure holding display callback functions.

Returns:

0 if everything is OK, < 0 otherwise