/*
* 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.
*/
package org.apache.lucene.util;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.nio.file.Path;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.store.FSLockFactory;
import org.apache.lucene.store.LockFactory;
/**
* Class containing some useful methods used by command line tools
*
*/
public final class CommandLineUtil {
private CommandLineUtil() {
}
/**
* Creates a specific FSDirectory instance starting from its class name, using the default lock factory
* @param clazzName The name of the FSDirectory class to load
* @param path The path to be used as parameter constructor
* @return the new FSDirectory instance
*/
public static FSDirectory newFSDirectory(String clazzName, Path path) {
return newFSDirectory(clazzName, path, FSLockFactory.getDefault());
}
/**
* Creates a specific FSDirectory instance starting from its class name
* @param clazzName The name of the FSDirectory class to load
* @param path The path to be used as parameter constructor
* @param lf The lock factory to be used
* @return the new FSDirectory instance
*/
public static FSDirectory newFSDirectory(String clazzName, Path path, LockFactory lf) {
try {
final Class<? extends FSDirectory> clazz = loadFSDirectoryClass(clazzName);
return newFSDirectory(clazz, path, lf);
} catch (ClassNotFoundException e) {
throw new IllegalArgumentException(FSDirectory.class.getSimpleName()
+ " implementation not found: " + clazzName, e);
} catch (ClassCastException e) {
throw new IllegalArgumentException(clazzName + " is not a " + FSDirectory.class.getSimpleName()
+ " implementation", e);
} catch (NoSuchMethodException e) {
throw new IllegalArgumentException(clazzName + " constructor with "
+ Path.class.getSimpleName() + " as parameter not found", e);
} catch (Exception e) {
throw new IllegalArgumentException("Error creating " + clazzName + " instance", e);
}
}
/**
* Loads a specific Directory implementation
* @param clazzName The name of the Directory class to load
* @return The Directory class loaded
* @throws ClassNotFoundException If the specified class cannot be found.
*/
public static Class<? extends Directory> loadDirectoryClass(String clazzName)
throws ClassNotFoundException {
return Class.forName(adjustDirectoryClassName(clazzName)).asSubclass(Directory.class);
}
/**
* Loads a specific FSDirectory implementation
* @param clazzName The name of the FSDirectory class to load
* @return The FSDirectory class loaded
* @throws ClassNotFoundException If the specified class cannot be found.
*/
public static Class<? extends FSDirectory> loadFSDirectoryClass(String clazzName)
throws ClassNotFoundException {
return Class.forName(adjustDirectoryClassName(clazzName)).asSubclass(FSDirectory.class);
}
private static String adjustDirectoryClassName(String clazzName) {
if (clazzName == null || clazzName.trim().length() == 0) {
throw new IllegalArgumentException("The " + FSDirectory.class.getSimpleName()
+ " implementation must not be null or empty");
}
if (clazzName.indexOf(".") == -1) {// if not fully qualified, assume .store
clazzName = Directory.class.getPackage().getName() + "." + clazzName;
}
return clazzName;
}
/**
* Creates a new specific FSDirectory instance
* @param clazz The class of the object to be created
* @param path The file to be used as parameter constructor
* @return The new FSDirectory instance
* @throws NoSuchMethodException If the Directory does not have a constructor that takes <code>Path</code>.
* @throws InstantiationException If the class is abstract or an interface.
* @throws IllegalAccessException If the constructor does not have public visibility.
* @throws InvocationTargetException If the constructor throws an exception
*/
public static FSDirectory newFSDirectory(Class<? extends FSDirectory> clazz, Path path)
throws ReflectiveOperationException {
return newFSDirectory(clazz, path, FSLockFactory.getDefault());
}
/**
* Creates a new specific FSDirectory instance
* @param clazz The class of the object to be created
* @param path The file to be used as parameter constructor
* @param lf The lock factory to be used
* @return The new FSDirectory instance
* @throws NoSuchMethodException If the Directory does not have a constructor that takes <code>Path</code>.
* @throws InstantiationException If the class is abstract or an interface.
* @throws IllegalAccessException If the constructor does not have public visibility.
* @throws InvocationTargetException If the constructor throws an exception
*/
public static FSDirectory newFSDirectory(Class<? extends FSDirectory> clazz, Path path, LockFactory lf)
throws ReflectiveOperationException {
// Assuming every FSDirectory has a ctor(Path):
Constructor<? extends FSDirectory> ctor = clazz.getConstructor(Path.class, LockFactory.class);
return ctor.newInstance(path, lf);
}
}