org.tigris.subversion.javahl.NativeResources Maven / Gradle / Ivy
/**
* @copyright
* ====================================================================
* Copyright (c) 2005 CollabNet. All rights reserved.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at http://subversion.tigris.org/license-1.html.
* If newer versions of this license are posted there, you may use a
* newer version instead, at your option.
*
* This software consists of voluntary contributions made by many
* individuals. For exact contribution history, see the revision
* history and logs, available at http://subversion.tigris.org/.
* ====================================================================
* @endcopyright
*/
package org.tigris.subversion.javahl;
/**
* Handles activities related to management of native resouces
* (e.g. loading of native libraries).
*/
class NativeResources
{
/**
* Version information about the underlying native libraries.
*/
static Version version;
/**
* Load the required native library whose path is specified by the
* system property subversion.native.library (which
* can be passed to the JVM on start-up using an argument like
* -Dsubversion.native.library=/usr/local/lib/libsvnjavahl-1.so).
* If the system property is not specified or cannot be loaded,
* attempt to load the library using its expected name, and the
* platform-dependent loading mechanism.
*
* @throws UnsatisfiedLinkError If the native library cannot be
* loaded.
* @throws LinkageError If the version of the loaded native
* library is not compatible with this version of JavaHL's Java
* APIs.
* @since 1.3.0
*/
public static synchronized void loadNativeLibrary()
{
UnsatisfiedLinkError loadException = null;
// If the user specified the fully qualified path to the
// native library, try loading that first.
try
{
String specifiedLibraryName =
System.getProperty("subversion.native.library");
if (specifiedLibraryName != null)
{
System.load(specifiedLibraryName);
init();
return;
}
}
catch (UnsatisfiedLinkError ex)
{
// Since the user explicitly specified this path, this is
// the best error to return if no other method succeeds.
loadException = ex;
}
// Try to load the library by its name. Failing that, try to
// load it by its old name.
String[] libraryNames = {"svnjavahl-1", "libsvnjavahl-1", "svnjavahl"};
for (int i = 0; i < libraryNames.length; i++)
{
try
{
System.loadLibrary(libraryNames[i]);
init();
return;
}
catch (UnsatisfiedLinkError ex)
{
if (loadException == null)
{
loadException = ex;
}
}
}
// Re-throw the most relevant exception.
if (loadException == null)
{
// This could only happen as the result of a programming error.
loadException = new UnsatisfiedLinkError("Unable to load JavaHL " +
"native library");
}
throw loadException;
}
/**
* Initializer for native resources to be invoked after
* the native library has been loaded. Sets library version
* information, and initializes the re-entrance hack for native
* code.
* @throws LinkageError If the version of the loaded native
* library is not compatible with this version of JavaHL's Java
* APIs.
*/
private static final void init()
{
initNativeLibrary();
version = new Version();
if (!version.isAtLeast(1, 5, 0))
{
throw new LinkageError("Native library version must be at least " +
"1.5.0, but is only " + version);
}
}
/**
* Initialize the native library layer.
* @since 1.5.0
*/
private static native void initNativeLibrary();
}