SimpleCache.java
package org.aspectj.weaver.tools.cache;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.security.ProtectionDomain;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;
import java.util.zip.CRC32;
import org.aspectj.weaver.Dump;
import org.aspectj.weaver.tools.Trace;
import org.aspectj.weaver.tools.TraceFactory;
/*******************************************************************************
* Copyright (c) 2012 Contributors.
* All rights reserved.
* This program and the accompanying materials are made available
* under the terms of the Eclipse Public License v 2.0
* which accompanies this distribution and is available at
* https://www.eclipse.org/org/documents/epl-2.0/EPL-2.0.txt
*
* Contributors:
* Abraham Nevado (lucierna) initial implementation
********************************************************************************/
public class SimpleCache {
private static final String SAME_BYTES_STRING = "IDEM";
static final byte[] SAME_BYTES = SAME_BYTES_STRING.getBytes(StandardCharsets.UTF_8);
private final Map<String, byte[]> cacheMap;
private boolean enabled = false;
// cache for generated classes
private Map<String, byte[]> generatedCache;
private static final String GENERATED_CACHE_SUBFOLDER = "panenka.cache";
private static final String GENERATED_CACHE_SEPARATOR = ";";
public static final String IMPL_NAME = "shared";
protected SimpleCache(String folder, boolean enabled) {
this.enabled = enabled;
cacheMap = Collections.synchronizedMap(StoreableCachingMap.init(folder));
if (enabled) {
String generatedCachePath = folder + File.separator + GENERATED_CACHE_SUBFOLDER;
File f = new File(generatedCachePath);
if (!f.exists()) {
f.mkdir();
}
generatedCache = Collections.synchronizedMap(StoreableCachingMap.init(generatedCachePath, 0));
}
}
/**
* Get bytes for given class from cache. If necessary, define and initialise the class first.
*
* @param classname name of class to be retrieved from the cache
* @param bytes class bytes (used to calculate cache key)
* @param loader class loader
* @param protectionDomain protection domain
*
* @return {@code null}, if the cache is disabled or if it contains no entry for the given class. An
* {@code Optional<byte[]>} value, if the cache knows about the class. The optional will be empty, if the cache entry
* represents and unwoven class, i.e. its bytes are identical to the original bytes.
*/
@SuppressWarnings("OptionalAssignedToNull")
public Optional<byte[]> getAndInitialize(
String classname,
byte[] bytes,
ClassLoader loader,
ProtectionDomain protectionDomain
)
{
if (!enabled) {
// Cache disabled
return null;
}
byte[] res = get(classname, bytes);
if (Arrays.equals(SAME_BYTES, res)) {
// Cache hit: unwoven class
return Optional.empty();
}
if (res != null) {
// Cache hit: woven class
initializeClass(classname, res, loader, protectionDomain);
return Optional.of(res);
}
// Cache miss
return null;
}
private byte[] get(String classname, byte[] bytes) {
String key = generateKey(classname, bytes);
return cacheMap.get(key);
}
public void put(String classname, byte[] origbytes, byte[] wovenbytes) {
if (!enabled) {
return;
}
String key = generateKey(classname, origbytes);
if (wovenbytes == null || Arrays.equals(origbytes, wovenbytes)) {
cacheMap.put(key, SAME_BYTES);
return;
}
cacheMap.put(key, wovenbytes);
}
private String generateKey(String classname, byte[] bytes) {
CRC32 checksum = new CRC32();
checksum.update(bytes);
long crc = checksum.getValue();
classname = classname.replace("/", ".");
return classname + "-" + crc;
}
private static class StoreableCachingMap extends HashMap {
// TODO: This class extends a raw HashMap, but instances of this class are assigned to fields
// Map<String, byte[]> cacheMap and Map<String, byte[]> generatedCache without casts. However, we cannot
// simply declare 'extends HashMap<String, byte[]>', because 'put' writes String values (paths) when given
// byte[] ones, while 'get' geturns byte[] ones, which is inconsistent. I.e., superficially the class behaves
// like a Map<String, byte[]>, while not really being one. This is ugly and hard to understand.
private final String folder;
private static final String CACHENAMEIDX = "cache.idx";
private long lastStored = System.currentTimeMillis();
private static final int DEF_STORING_TIMER = 60000; //ms
private final int storingTimer;
private transient Trace trace;
private void initTrace() {
trace = TraceFactory.getTraceFactory().getTrace(StoreableCachingMap.class);
}
private StoreableCachingMap(String folder, int storingTimer) {
this.folder = folder;
initTrace();
this.storingTimer = storingTimer;
}
public static StoreableCachingMap init(String folder) {
return init(folder, DEF_STORING_TIMER);
}
public static StoreableCachingMap init(String folder, int storingTimer) {
File file = new File(folder + File.separator + CACHENAMEIDX);
if (file.exists()) {
try (ObjectInputStream in = new ObjectInputStream(Files.newInputStream(file.toPath()))) {
// Deserialize the object
StoreableCachingMap sm = (StoreableCachingMap) in.readObject();
sm.initTrace();
return sm;
}
catch (Exception e) {
Trace trace = TraceFactory.getTraceFactory().getTrace(StoreableCachingMap.class);
trace.error("Error reading Storable Cache", e);
}
}
return new StoreableCachingMap(folder, storingTimer);
}
@Override
public Object get(Object obj) {
try {
if (super.containsKey(obj)) {
String path = (String) super.get(obj);
if (path.equals(SAME_BYTES_STRING)) {
return SAME_BYTES;
}
return readFromPath(path);
}
else {
return null;
}
}
catch (IOException e) {
trace.error("Error reading key:" + obj.toString(), e);
Dump.dumpWithException(e);
}
return null;
}
@Override
public Object put(Object key, Object value) {
try {
String path;
byte[] valueBytes = (byte[]) value;
if (Arrays.equals(valueBytes, SAME_BYTES)) {
path = SAME_BYTES_STRING;
}
else {
path = writeToPath((String) key, valueBytes);
}
Object result = super.put(key, path);
storeMap();
return result;
}
catch (IOException e) {
trace.error("Error inserting in cache: key:" + key + "; value:" + value.toString(), e);
Dump.dumpWithException(e);
}
return null;
}
public void storeMap() {
long now = System.currentTimeMillis();
if ((now - lastStored) < storingTimer) {
return;
}
File file = new File(folder + File.separator + CACHENAMEIDX);
try (ObjectOutputStream out = new ObjectOutputStream(Files.newOutputStream(file.toPath()))) {
// Deserialize the object
out.writeObject(this);
lastStored = now;
}
catch (Exception e) {
trace.error("Error storing cache; cache file:" + file.getAbsolutePath(), e);
Dump.dumpWithException(e);
}
}
private byte[] readFromPath(String fullPath) throws IOException {
try (
FileInputStream is = new FileInputStream(fullPath);
ByteArrayOutputStream buffer = new ByteArrayOutputStream()
) {
int nRead;
byte[] data = new byte[16384];
while ((nRead = is.read(data, 0, data.length)) != -1) {
buffer.write(data, 0, nRead);
}
buffer.flush();
return buffer.toByteArray();
}
catch (FileNotFoundException e) {
// May be caused by a generated class that has been stored in generated cache but not saved in cache folder
System.out.println("FileNotFoundExceptions: The aspectj cache is corrupt. Please clean it and reboot the server. Cache path:" + this.folder);
e.printStackTrace();
return null;
}
}
private String writeToPath(String key, byte[] bytes) throws IOException {
String fullPath = folder + File.separator + key;
try (FileOutputStream fos = new FileOutputStream(fullPath)) {
fos.write(bytes);
fos.flush();
}
return fullPath;
}
}
private void initializeClass(
String className, byte[] bytes,
ClassLoader loader, ProtectionDomain protectionDomain
)
{
String[] generatedClassesNames = getGeneratedClassesNames(className, bytes);
if (generatedClassesNames == null) {
return;
}
for (String generatedClassName : generatedClassesNames) {
byte[] generatedBytes = get(generatedClassName, bytes);
if (protectionDomain == null) {
defineClass(loader, generatedClassName, generatedBytes);
}
else {
defineClass(loader, generatedClassName, generatedBytes, protectionDomain);
}
}
}
private String[] getGeneratedClassesNames(String className, byte[] bytes) {
String key = generateKey(className, bytes);
byte[] readBytes = generatedCache.get(key);
if (readBytes == null) {
return null;
}
String readString = new String(readBytes);
return readString.split(GENERATED_CACHE_SEPARATOR);
}
public void addGeneratedClassesNames(String parentClassName, byte[] parentBytes, String generatedClassName) {
if (!enabled) {
return;
}
String key = generateKey(parentClassName, parentBytes);
byte[] storedBytes = generatedCache.get(key);
if (storedBytes == null) {
generatedCache.put(key, generatedClassName.getBytes());
}
else {
String storedClasses = new String(storedBytes);
storedClasses += GENERATED_CACHE_SEPARATOR + generatedClassName;
generatedCache.put(key, storedClasses.getBytes());
}
}
private Method defineClassMethod = null;
private Method defineClassWithProtectionDomainMethod = null;
private void defineClass(ClassLoader loader, String name, byte[] bytes) {
try {
if (defineClassMethod == null) {
// TODO: Replace by class definition strategy used in ClassLoaderWeavingAdaptor
defineClassMethod = ClassLoader.class.getDeclaredMethod(
"defineClass",
String.class, bytes.getClass(), int.class, int.class
);
defineClassMethod.setAccessible(true);
}
defineClassMethod.invoke(loader, name, bytes, 0, bytes.length);
}
catch (InvocationTargetException e) {
if (e.getTargetException() instanceof LinkageError) {
e.printStackTrace();
}
else {
System.out.println("define generated class failed" + e.getTargetException());
}
}
catch (Exception e) {
e.printStackTrace();
Dump.dumpWithException(e);
}
}
private void defineClass(ClassLoader loader, String name, byte[] bytes, ProtectionDomain protectionDomain) {
try {
if (defineClassWithProtectionDomainMethod == null) {
// TODO: Replace by class definition strategy used in ClassLoaderWeavingAdaptor
defineClassWithProtectionDomainMethod = ClassLoader.class.getDeclaredMethod(
"defineClass",
String.class, bytes.getClass(), int.class, int.class, ProtectionDomain.class
);
defineClassWithProtectionDomainMethod.setAccessible(true);
}
defineClassWithProtectionDomainMethod.invoke(loader, name, bytes, 0, bytes.length, protectionDomain);
}
catch (InvocationTargetException e) {
if (e.getTargetException() instanceof LinkageError) {
e.printStackTrace();
// is already defined (happens for X$ajcMightHaveAspect
// interfaces since aspects are reweaved)
// TODO maw I don't think this is OK and
}
else {
e.printStackTrace();
}
}
catch (NullPointerException e) {
System.out.println("NullPointerException loading class:" + name + ". Probabily caused by a corruput cache. Please clean it and reboot the server");
}
catch (Exception e) {
e.printStackTrace();
Dump.dumpWithException(e);
}
}
}