com.jogamp.common.os

Class NativeLibrary

java.lang.Object

com.jogamp.common.os.NativeLibrary

All Implemented Interfaces:

DynamicLookupHelper

public final class NativeLibrary
extends Object
implements DynamicLookupHelper

Provides low-level, relatively platform-independent access to shared ("native") libraries. The core library routines System.load() and System.loadLibrary() in general provide suitable functionality for applications using native code, but are not flexible enough to support certain kinds of glue code generation and deployment strategies. This class supports direct linking of native libraries to other shared objects not necessarily installed on the system (in particular, via the use of dlopen(RTLD_GLOBAL) on Unix platforms) as well as manual lookup of function names to support e.g. GlueGen's ProcAddressTable glue code generation style without additional supporting code needed in the generated library.

Field Summary

Fields inherited from interface com.jogamp.common.os.DynamicLookupHelper

DEBUG, DEBUG_LOOKUP

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Closes this native library.
long	dynamicLookupFunction(String funcName) Returns the function handle for function 'funcName'.
static long	dynamicLookupFunctionGlobal(String funcName) Looks up the given function name in all loaded libraries.
static List<String>	enumerateLibraryPaths(String windowsLibName, String unixLibName, String macOSXLibName, boolean searchSystemPathFirst, ClassLoader loader) Given the base library names (no prefixes/suffixes) for the various platforms, enumerate the possible locations and names of the indicated native library on the system.
static String	findLibrary(String libName, ClassLoader loader)
long	getLibraryHandle() Retrieves the low-level library handle from this NativeLibrary object.
String	getLibraryPath() Retrieves the path under which this library was opened.
boolean	isFunctionAvailable(String funcName) Queries whether function 'funcName' is available.
static boolean	isFunctionAvailableGlobal(String funcName) Looks up the given function name in all loaded libraries.
static String	isValidNativeLibraryName(String libName, boolean isLowerCaseAlready) Comparison of prefix and suffix of the given libName's basename is performed case insensitive
static NativeLibrary	open(String libName, ClassLoader loader) Opens the given native library, assuming it has the same base name on all platforms, looking first in the system's search path, and in the context of the specified ClassLoader, which is used to help find the library in the case of e.g.
static NativeLibrary	open(String libName, ClassLoader loader, boolean global) Opens the given native library, assuming it has the same base name on all platforms, looking first in the system's search path, and in the context of the specified ClassLoader, which is used to help find the library in the case of e.g.
static NativeLibrary	open(String windowsLibName, String unixLibName, String macOSXLibName, boolean searchSystemPathFirst, ClassLoader loader) Opens the given native library, assuming it has the given base names (no "lib" prefix or ".dll/.so/.dylib" suffix) on the Windows, Unix and Mac OS X platforms, respectively, and in the context of the specified ClassLoader, which is used to help find the library in the case of e.g.
static NativeLibrary	open(String windowsLibName, String unixLibName, String macOSXLibName, boolean searchSystemPathFirst, ClassLoader loader, boolean global)
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

toString

public final String toString()

Overrides:

toString in class Object

open

public static final NativeLibrary open(String libName,
                 ClassLoader loader)

Opens the given native library, assuming it has the same base name on all platforms, looking first in the system's search path, and in the context of the specified ClassLoader, which is used to help find the library in the case of e.g. Java Web Start.

open

public static final NativeLibrary open(String libName,
                 ClassLoader loader,
                 boolean global)

Opens the given native library, assuming it has the same base name on all platforms, looking first in the system's search path, and in the context of the specified ClassLoader, which is used to help find the library in the case of e.g. Java Web Start.

open

public static final NativeLibrary open(String windowsLibName,
                 String unixLibName,
                 String macOSXLibName,
                 boolean searchSystemPathFirst,
                 ClassLoader loader)

Opens the given native library, assuming it has the given base names (no "lib" prefix or ".dll/.so/.dylib" suffix) on the Windows, Unix and Mac OS X platforms, respectively, and in the context of the specified ClassLoader, which is used to help find the library in the case of e.g. Java Web Start. The searchSystemPathFirst argument changes the behavior to first search the default system path rather than searching it last. Note that we do not currently handle DSO versioning on Unix. Experience with JOAL and OpenAL has shown that it is extremely problematic to rely on a specific .so version (for one thing, ClassLoader.findLibrary on Unix doesn't work with files not ending in .so, for example .so.0), and in general if this dynamic loading facility is used correctly the version number will be irrelevant.

open

public static final NativeLibrary open(String windowsLibName,
                 String unixLibName,
                 String macOSXLibName,
                 boolean searchSystemPathFirst,
                 ClassLoader loader,
                 boolean global)

dynamicLookupFunction

public final long dynamicLookupFunction(String funcName)

Description copied from interface: DynamicLookupHelper

Returns the function handle for function 'funcName'.

Specified by:

dynamicLookupFunction in interface DynamicLookupHelper

isFunctionAvailable

public final boolean isFunctionAvailable(String funcName)

Description copied from interface: DynamicLookupHelper

Queries whether function 'funcName' is available.

Specified by:

isFunctionAvailable in interface DynamicLookupHelper

dynamicLookupFunctionGlobal

public static final long dynamicLookupFunctionGlobal(String funcName)

Looks up the given function name in all loaded libraries.

isFunctionAvailableGlobal

public static final boolean isFunctionAvailableGlobal(String funcName)

Looks up the given function name in all loaded libraries.

getLibraryHandle

public final long getLibraryHandle()

Retrieves the low-level library handle from this NativeLibrary object. On the Windows platform this is an HMODULE, and on Unix and Mac OS X platforms the void* result of calling dlopen().

getLibraryPath

public final String getLibraryPath()

Retrieves the path under which this library was opened.

close

public final void close()

Closes this native library. Further lookup operations are not allowed after calling this method.

isValidNativeLibraryName

public static final String isValidNativeLibraryName(String libName,
                              boolean isLowerCaseAlready)

Comparison of prefix and suffix of the given libName's basename is performed case insensitive

Parameters:

libName - the full path library name with prefix and suffix

isLowerCaseAlready - indicates if libName is already lower-case

Returns:

basename of libName w/o path, ie. /usr/lib/libDrinkBeer.so -> DrinkBeer on Unix systems, but null on Windows.

enumerateLibraryPaths

public static final List<String> enumerateLibraryPaths(String windowsLibName,
                                 String unixLibName,
                                 String macOSXLibName,
                                 boolean searchSystemPathFirst,
                                 ClassLoader loader)

Given the base library names (no prefixes/suffixes) for the various platforms, enumerate the possible locations and names of the indicated native library on the system.

findLibrary

public static final String findLibrary(String libName,
                 ClassLoader loader)