org.apache.mina.transport.socket.apr.AprLibrary Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* 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
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* under the License.
*
*/
package org.apache.mina.transport.socket.apr;
import org.apache.tomcat.jni.Library;
import org.apache.tomcat.jni.Pool;
/**
* Internal singleton used for initializing correctly the APR native library
* and the associated root memory pool.
*
* It'll finalize nicely the native resources (libraries and memory pools).
*
* Each memory pool used in the APR transport module needs to be children of the
* root pool AprLibrary#getRootPool().
*
* @author Apache MINA Project
*/
class AprLibrary {
// is APR library was initialized (load of native libraries)
private static AprLibrary library = null;
/**
* get the shared instance of APR library, if none, initialize one
* @return the current APR library singleton
*/
static synchronized AprLibrary getInstance() {
if (!isInitialized())
initialize();
return library;
}
/**
* initialize the APR Library by loading the associated native libraries
* and creating the associated singleton
*/
private static synchronized void initialize() {
if (library == null)
library = new AprLibrary();
}
/**
* is the APR library was initialized.
* @return true if the Library is initialized, false otherwise
*/
static synchronized boolean isInitialized() {
return library != null;
}
// APR memory pool (package wide mother pool)
private final long pool;
/**
* APR library singleton constructor. Called only when accessing the
* singleton the first time.
* It's initializing an APR memory pool for the whole package (a.k.a mother or root pool).
*/
private AprLibrary() {
try {
Library.initialize(null);
} catch (Throwable t) {
throw new RuntimeException("Error loading Apache Portable Runtime (APR).", t);
}
pool = Pool.create(0);
}
@Override
protected void finalize() throws Throwable {
super.finalize();
Pool.destroy(pool);
}
/**
* get the package wide root pool, the mother of all the pool created
* in APR transport module.
* @return number identifying the root pool
*/
long getRootPool() {
return pool;
}
}