/**
* @copyright
* ====================================================================
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
* ====================================================================
* @endcopyright
*/
package org.apache.subversion.javahl;
import org.apache.subversion.javahl.types.Version;
/**
* Handles activities related to management of native resouces
* (e.g. loading of native libraries).
*
* Public for backward compat. This class may disappear in future versions
* of the API. You've been warned.
*/
public class NativeResources
{
/**
* @return Version information about the underlying native libraries.
*/
private static Version version;
/**
* Returns version information about the underlying native libraries.
*
* @return version
*
*/
public static Version getVersion() {
return version;
}
/**
* Load the required native library whose path is specified by the
* system property <code>subversion.native.library</code> (which
* can be passed to the JVM on start-up using an argument like
* <code>-Dsubversion.native.library=/usr/local/lib/libsvnjavahl-1.so</code>).
* 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.
*/
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 (String libraryName : libraryNames)
{
try
{
System.loadLibrary(libraryName);
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 <em>after</em>
* 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.
*/
private static native void initNativeLibrary();
}