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The Waikato Environment for Knowledge Analysis (WEKA), a machine
learning workbench. This version represents the developer version, the
"bleeding edge" of development, you could say. New functionality gets added
to this version.
/*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see > m_stores =
new LinkedHashMap>();
/**
* Establish the home directory for the store
*
* @throws IOException if a problem occurs
*/
protected synchronized void establishStoreHome() throws IOException {
if (m_storeDirOK) {
return;
}
if (!m_storeHome.exists()) {
if (!m_storeHome.mkdir()) {
throw new IOException("Unable to create the metastore directory: "
+ m_storeHome.toString());
}
}
if (!m_storeHome.isDirectory()) {
throw new IOException("The metastore (" + m_storeHome
+ ") seems to exist, but it isn't a directory!");
}
m_storeDirOK = true;
lockStore();
// now scan the contents
File[] contents = m_storeHome.listFiles();
for (File f : contents) {
if (f.isDirectory()) {
Map store = new LinkedHashMap();
m_stores.put(f.getName(), store);
File[] storeEntries = f.listFiles();
for (File se : storeEntries) {
store.put(se.getName(), se);
}
}
}
unlockStore();
}
@Override
public Set listMetaStores() throws IOException {
return m_stores.keySet();
}
@Override
public Set listMetaStoreEntries(String storeName) throws IOException {
establishStoreHome();
Set results = new HashSet();
Map store = m_stores.get(storeName);
if (store != null) {
results.addAll(store.keySet());
}
return results;
}
@Override
public synchronized Set listMetaStoreEntries(String storeName,
String prefix) throws IOException {
establishStoreHome();
Set matches = new HashSet();
Map store = m_stores.get(storeName);
if (store != null) {
for (Map.Entry e : store.entrySet()) {
if (e.getKey().startsWith(prefix)) {
matches.add(e.getKey());
}
}
}
return matches;
}
@Override
public Object getEntry(String storeName, String name, Class clazz)
throws IOException {
establishStoreHome();
Map store = m_stores.get(storeName);
if (store != null) {
if (store.containsKey(name)) {
File toLoad = store.get(name);
try {
lockStore();
XMLBasicSerialization deserializer = getSerializer();
Object loaded = deserializer.read(toLoad);
if (loaded.getClass().equals(clazz)) {
throw new IOException(
"Deserialized entry (" + loaded.getClass().getName()
+ ") was not " + "the expected class: " + clazz.getName());
}
return loaded;
} catch (Exception ex) {
throw new IOException(ex);
} finally {
unlockStore();
}
}
}
return null;
}
@Override
public void createStore(String storeName) throws IOException {
File store = new File(m_storeHome, storeName);
if (store.exists()) {
throw new IOException("Meta store '" + storeName + "' already exists!");
}
lockStore();
try {
if (!store.mkdir()) {
throw new IOException(
"Unable to create meta store '" + storeName + "'");
}
} finally {
unlockStore();
}
}
@Override
public synchronized void storeEntry(String storeName, String name,
Object toStore) throws IOException {
establishStoreHome();
Map store = m_stores.get(storeName);
if (store == null) {
createStore(storeName);
store = new LinkedHashMap();
m_stores.put(storeName, store);
}
File loc =
new File(m_storeHome.toString() + File.separator + storeName, name);
store.put(name, loc);
try {
lockStore();
XMLBasicSerialization serializer = getSerializer();
serializer.write(loc, toStore);
} catch (Exception ex) {
throw new IOException(ex);
} finally {
unlockStore();
}
}
/**
* Lock the store
*
* @throws IOException if a problem occurs
*/
protected void lockStore() throws IOException {
int totalWaitTime = 0;
while (true) {
File lock = new File(m_storeHome, ".lock");
if (lock.createNewFile()) {
return;
}
try {
Thread.sleep(200);
} catch (InterruptedException ex) {
throw new RuntimeException(ex);
}
totalWaitTime += 200;
if (totalWaitTime > 5000) {
throw new IOException("Unable to lock store within 5 seconds");
}
}
}
/**
* Unlocks the metastore
*/
protected void unlockStore() {
File lock = new File(m_storeHome, ".lock");
lock.delete();
}
/**
* Gets a serializer to use. Creates a subclass of
* {@code XMLBasicSerialization} that has allowed properties set for common
* option handlers.
*
* @return a serializer instance
*/
protected XMLBasicSerialization getSerializer() {
try {
XMLBasicSerialization ser = new XMLBasicSerialization() {
public void clear() throws Exception {
super.clear();
m_Properties.addAllowed(weka.classifiers.Classifier.class, "debug");
m_Properties.addAllowed(weka.classifiers.Classifier.class, "options");
m_Properties.addAllowed(weka.associations.Associator.class,
"options");
m_Properties.addAllowed(weka.clusterers.Clusterer.class, "options");
m_Properties.addAllowed(weka.filters.Filter.class, "options");
m_Properties.addAllowed(weka.core.converters.Saver.class, "options");
m_Properties.addAllowed(weka.core.converters.Loader.class, "options");
m_Properties.addAllowed(weka.attributeSelection.ASSearch.class,
"options");
m_Properties.addAllowed(weka.attributeSelection.ASEvaluation.class,
"options");
m_Properties.addAllowed(weka.core.converters.DatabaseSaver.class,
"options");
m_Properties.addAllowed(weka.core.converters.DatabaseLoader.class,
"options");
m_Properties.addAllowed(
weka.core.converters.TextDirectoryLoader.class, "options");
// we assume that classes implementing SplitEvaluator also implement
// OptionHandler
m_Properties.addAllowed(weka.experiment.SplitEvaluator.class,
"options");
// we assume that classes implementing ResultProducer also implement
// OptionHandler
m_Properties.addAllowed(weka.experiment.ResultProducer.class,
"options");
}
};
ser.setSuppressWarnings(true);
return ser;
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}
}