/*
* Copyright (C) 2011 Google Inc.
*
* Licensed 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 com.google.caliper.util;
import com.google.common.collect.ImmutableBiMap;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Maps;
import com.google.common.io.ByteSource;
import com.google.common.io.Closer;
import com.google.common.io.Resources;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Member;
import java.lang.reflect.Modifier;
import java.util.Map;
import java.util.Properties;
import java.util.Set;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
public final class Util {
private Util() {}
// Users have no idea that nested classes are identified with '$', not '.', so if class lookup
// fails try replacing the last . with $.
public static Class<?> lenientClassForName(String className) throws ClassNotFoundException {
try {
// TODO: consider whether any control over class loader is really needed here
// (forName(className, true, Thread.currentThread().getContextClassLoader())?)
return Class.forName(className);
} catch (ClassNotFoundException ignored) {
// try replacing the last dot with a $, in case that helps
// example: tutorial.Tutorial.Benchmark1 becomes tutorial.Tutorial$Benchmark1
// amusingly, the $ character means three different things in this one line alone
String newName = className.replaceFirst("\\.([^.]+)$", "\\$$1");
return Class.forName(newName);
}
}
public static ImmutableMap<String, String> loadProperties(ByteSource is) throws IOException {
Properties props = new Properties();
Closer closer = Closer.create();
InputStream in = closer.register(is.openStream());
try {
props.load(in);
} finally {
closer.close();
}
return Maps.fromProperties(props);
}
public static ByteSource resourceSupplier(final Class<?> c, final String name) {
return Resources.asByteSource(c.getResource(name));
}
public static <T> ImmutableMap<String, T> prefixedSubmap(
Map<String, T> props, String prefix) {
ImmutableMap.Builder<String, T> submapBuilder = ImmutableMap.builder();
for (Map.Entry<String, T> entry : props.entrySet()) {
String name = entry.getKey();
if (name.startsWith(prefix)) {
submapBuilder.put(name.substring(prefix.length()), entry.getValue());
}
}
return submapBuilder.build();
}
public static boolean isPublic(Member member) {
return Modifier.isPublic(member.getModifiers());
}
public static boolean isStatic(Member member) {
return Modifier.isStatic(member.getModifiers());
}
private static final long FORCE_GC_TIMEOUT_SECS = 2;
public static void forceGc() {
System.gc();
System.runFinalization();
final CountDownLatch latch = new CountDownLatch(1);
new Object() {
@Override protected void finalize() {
latch.countDown();
}
};
System.gc();
System.runFinalization();
try {
latch.await(FORCE_GC_TIMEOUT_SECS, TimeUnit.SECONDS);
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
}
}
public static <T> ImmutableBiMap<T, String> assignNames(Set<T> items) {
ImmutableList<T> itemList = ImmutableList.copyOf(items);
ImmutableBiMap.Builder<T, String> itemNamesBuilder = ImmutableBiMap.builder();
for (int i = 0; i < itemList.size(); i++) {
itemNamesBuilder.put(itemList.get(i), generateUniqueName(i));
}
return itemNamesBuilder.build();
}
private static String generateUniqueName(int index) {
if (index < 26) {
return String.valueOf((char) ('A' + index));
} else {
return generateUniqueName(index / 26 - 1) + generateUniqueName(index % 26);
}
}
}