init
This commit is contained in:
@@ -0,0 +1,208 @@
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/*
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||||
* 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.
|
||||
*/
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||||
package org.apache.tomcat.util.collections;
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import java.util.AbstractMap;
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import java.util.AbstractSet;
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import java.util.HashMap;
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import java.util.Iterator;
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import java.util.Locale;
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import java.util.Map;
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import java.util.Set;
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import org.apache.tomcat.util.res.StringManager;
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/**
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* A Map implementation that uses case-insensitive (using {@link
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* Locale#ENGLISH}) strings as keys.
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* <p>
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* Keys must be instances of {@link String}. Note that this means that
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* <code>null</code> keys are not permitted.
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* <p>
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* This implementation is not thread-safe.
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*
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* @param <V> Type of values placed in this Map.
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*/
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public class CaseInsensitiveKeyMap<V> extends AbstractMap<String,V> {
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private static final StringManager sm =
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StringManager.getManager(CaseInsensitiveKeyMap.class);
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private final Map<Key,V> map = new HashMap<>();
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@Override
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public V get(Object key) {
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return map.get(Key.getInstance(key));
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}
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@Override
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public V put(String key, V value) {
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Key caseInsensitiveKey = Key.getInstance(key);
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if (caseInsensitiveKey == null) {
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throw new NullPointerException(sm.getString("caseInsensitiveKeyMap.nullKey"));
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}
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return map.put(caseInsensitiveKey, value);
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}
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/**
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* {@inheritDoc}
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* <p>
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* <b>Use this method with caution</b>. If the input Map contains duplicate
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* keys when the keys are compared in a case insensitive manner then some
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* values will be lost when inserting via this method.
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*/
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@Override
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public void putAll(Map<? extends String, ? extends V> m) {
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super.putAll(m);
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}
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@Override
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public boolean containsKey(Object key) {
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return map.containsKey(Key.getInstance(key));
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}
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@Override
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public V remove(Object key) {
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return map.remove(Key.getInstance(key));
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}
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@Override
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public Set<Entry<String, V>> entrySet() {
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return new EntrySet<>(map.entrySet());
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}
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private static class EntrySet<V> extends AbstractSet<Entry<String,V>> {
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private final Set<Entry<Key,V>> entrySet;
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public EntrySet(Set<Map.Entry<Key,V>> entrySet) {
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this.entrySet = entrySet;
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}
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@Override
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public Iterator<Entry<String,V>> iterator() {
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return new EntryIterator<>(entrySet.iterator());
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}
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@Override
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public int size() {
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return entrySet.size();
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}
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}
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private static class EntryIterator<V> implements Iterator<Entry<String,V>> {
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private final Iterator<Entry<Key,V>> iterator;
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public EntryIterator(Iterator<Entry<Key,V>> iterator) {
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this.iterator = iterator;
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}
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@Override
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public boolean hasNext() {
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return iterator.hasNext();
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}
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@Override
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public Entry<String,V> next() {
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Entry<Key,V> entry = iterator.next();
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return new EntryImpl<>(entry.getKey().getKey(), entry.getValue());
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}
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@Override
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public void remove() {
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iterator.remove();
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}
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}
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private static class EntryImpl<V> implements Entry<String,V> {
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private final String key;
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private final V value;
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public EntryImpl(String key, V value) {
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this.key = key;
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this.value = value;
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}
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@Override
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public String getKey() {
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return key;
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}
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@Override
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public V getValue() {
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return value;
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}
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@Override
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public V setValue(V value) {
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throw new UnsupportedOperationException();
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}
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}
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private static class Key {
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private final String key;
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private final String lcKey;
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private Key(String key) {
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this.key = key;
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this.lcKey = key.toLowerCase(Locale.ENGLISH);
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}
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public String getKey() {
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return key;
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}
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@Override
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public int hashCode() {
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return lcKey.hashCode();
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}
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@Override
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public boolean equals(Object obj) {
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if (this == obj) {
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return true;
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}
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if (obj == null) {
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return false;
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}
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if (getClass() != obj.getClass()) {
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return false;
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}
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Key other = (Key) obj;
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return lcKey.equals(other.lcKey);
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}
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public static Key getInstance(Object o) {
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if (o instanceof String) {
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return new Key((String) o);
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}
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return null;
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||||
}
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}
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}
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59
java/org/apache/tomcat/util/collections/ConcurrentCache.java
Normal file
59
java/org/apache/tomcat/util/collections/ConcurrentCache.java
Normal file
@@ -0,0 +1,59 @@
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/*
|
||||
* 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.
|
||||
*/
|
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package org.apache.tomcat.util.collections;
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import java.util.Map;
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import java.util.WeakHashMap;
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import java.util.concurrent.ConcurrentHashMap;
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public final class ConcurrentCache<K,V> {
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private final int size;
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private final Map<K,V> eden;
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private final Map<K,V> longterm;
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public ConcurrentCache(int size) {
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this.size = size;
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this.eden = new ConcurrentHashMap<>(size);
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this.longterm = new WeakHashMap<>(size);
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}
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public V get(K k) {
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V v = this.eden.get(k);
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if (v == null) {
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synchronized (longterm) {
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v = this.longterm.get(k);
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}
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if (v != null) {
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this.eden.put(k, v);
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}
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}
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return v;
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}
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public void put(K k, V v) {
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if (this.eden.size() >= size) {
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synchronized (longterm) {
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this.longterm.putAll(this.eden);
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}
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this.eden.clear();
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}
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this.eden.put(k, v);
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}
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}
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@@ -0,0 +1,271 @@
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/*
|
||||
* 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.
|
||||
*/
|
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package org.apache.tomcat.util.collections;
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import java.lang.ref.Reference;
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import java.lang.ref.ReferenceQueue;
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import java.lang.ref.WeakReference;
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import java.util.AbstractMap;
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import java.util.AbstractSet;
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import java.util.Collection;
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import java.util.Iterator;
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import java.util.Map;
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import java.util.Objects;
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import java.util.Set;
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import java.util.concurrent.ConcurrentHashMap;
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import java.util.concurrent.ConcurrentMap;
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/**
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* Concurrent hash map that holds its keys via weak references. Unlike
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* <code>WeakHashMap</code> this class does not handle dead keys during common
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* access operations, but expects you to call its {@link #maintain()} method
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* periodically. Both keys and values are expected to be not-<code>null</code>.
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*
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* @param <K> The type of keys used with the Map instance
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* @param <V> The type of values used with the Map instance
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*/
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public class ManagedConcurrentWeakHashMap<K, V> extends AbstractMap<K, V> implements
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ConcurrentMap<K, V> {
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private final ConcurrentMap<Key, V> map = new ConcurrentHashMap<>();
|
||||
private final ReferenceQueue<Object> queue = new ReferenceQueue<>();
|
||||
|
||||
/**
|
||||
* Method, that has to be invoked periodically to clean dead keys from the
|
||||
* map.
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||||
*/
|
||||
public void maintain() {
|
||||
Key key;
|
||||
while ((key = (Key) queue.poll()) != null) {
|
||||
if (key.isDead()) {
|
||||
// No need to lookup if the key is not in the map
|
||||
continue;
|
||||
}
|
||||
key.ackDeath();
|
||||
map.remove(key);
|
||||
}
|
||||
}
|
||||
|
||||
private static class Key extends WeakReference<Object> {
|
||||
private final int hash;
|
||||
private boolean dead;
|
||||
|
||||
public Key(Object key, ReferenceQueue<Object> queue) {
|
||||
super(key, queue);
|
||||
hash = key.hashCode();
|
||||
}
|
||||
|
||||
@Override
|
||||
public int hashCode() {
|
||||
return hash;
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean equals(Object obj) {
|
||||
if (this == obj) {
|
||||
return true;
|
||||
}
|
||||
if (dead) {
|
||||
// Post-mortem cleanup looks for this specific Reference
|
||||
// instance
|
||||
return false;
|
||||
}
|
||||
if (!(obj instanceof Reference<?>)) {
|
||||
return false;
|
||||
}
|
||||
Object oA = get();
|
||||
Object oB = ((Reference<?>) obj).get();
|
||||
if (oA == oB) {
|
||||
return true;
|
||||
}
|
||||
if (oA == null || oB == null) {
|
||||
return false;
|
||||
}
|
||||
return oA.equals(oB);
|
||||
}
|
||||
|
||||
public void ackDeath() {
|
||||
this.dead = true;
|
||||
}
|
||||
|
||||
public boolean isDead() {
|
||||
return dead;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates Key instance to be used to store values in the map. It is
|
||||
* registered with the ReferenceQueue.
|
||||
*/
|
||||
private Key createStoreKey(Object key) {
|
||||
return new Key(key, queue);
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates Key instance to be used only to lookup values in the map. It is
|
||||
* not registered with the ReferenceQueue.
|
||||
*/
|
||||
private Key createLookupKey(Object key) {
|
||||
return new Key(key, null);
|
||||
}
|
||||
|
||||
@Override
|
||||
public int size() {
|
||||
return map.size();
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean isEmpty() {
|
||||
return map.isEmpty();
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean containsValue(Object value) {
|
||||
if (value == null) {
|
||||
return false;
|
||||
}
|
||||
return map.containsValue(value);
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean containsKey(Object key) {
|
||||
if (key == null) {
|
||||
return false;
|
||||
}
|
||||
return map.containsKey(createLookupKey(key));
|
||||
}
|
||||
|
||||
@Override
|
||||
public V get(Object key) {
|
||||
if (key == null) {
|
||||
return null;
|
||||
}
|
||||
return map.get(createLookupKey(key));
|
||||
}
|
||||
|
||||
@Override
|
||||
public V put(K key, V value) {
|
||||
Objects.requireNonNull(value);
|
||||
return map.put(createStoreKey(key), value);
|
||||
}
|
||||
|
||||
@Override
|
||||
public V remove(Object key) {
|
||||
return map.remove(createLookupKey(key));
|
||||
}
|
||||
|
||||
@Override
|
||||
public void clear() {
|
||||
map.clear();
|
||||
// maintain() clears the queue, though it is not 100% reliable,
|
||||
// as queue is populated by GC asynchronously
|
||||
maintain();
|
||||
}
|
||||
|
||||
@Override
|
||||
public V putIfAbsent(K key, V value) {
|
||||
Objects.requireNonNull(value);
|
||||
Key storeKey = createStoreKey(key);
|
||||
V oldValue = map.putIfAbsent(storeKey, value);
|
||||
if (oldValue != null) { // ack that key has not been stored
|
||||
storeKey.ackDeath();
|
||||
}
|
||||
return oldValue;
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean remove(Object key, Object value) {
|
||||
if (value == null) {
|
||||
return false;
|
||||
}
|
||||
return map.remove(createLookupKey(key), value);
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean replace(K key, V oldValue, V newValue) {
|
||||
Objects.requireNonNull(newValue);
|
||||
return map.replace(createLookupKey(key), oldValue, newValue);
|
||||
}
|
||||
|
||||
@Override
|
||||
public V replace(K key, V value) {
|
||||
Objects.requireNonNull(value);
|
||||
return map.replace(createLookupKey(key), value);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Collection<V> values() {
|
||||
return map.values();
|
||||
}
|
||||
|
||||
@Override
|
||||
public Set<Map.Entry<K, V>> entrySet() {
|
||||
return new AbstractSet<Map.Entry<K, V>>() {
|
||||
@Override
|
||||
public boolean isEmpty() {
|
||||
return map.isEmpty();
|
||||
}
|
||||
|
||||
@Override
|
||||
public int size() {
|
||||
return map.size();
|
||||
}
|
||||
|
||||
@Override
|
||||
public Iterator<Map.Entry<K, V>> iterator() {
|
||||
return new Iterator<Map.Entry<K, V>>() {
|
||||
private final Iterator<Map.Entry<Key, V>> it = map
|
||||
.entrySet().iterator();
|
||||
|
||||
@Override
|
||||
public boolean hasNext() {
|
||||
return it.hasNext();
|
||||
}
|
||||
|
||||
@Override
|
||||
public Map.Entry<K, V> next() {
|
||||
return new Map.Entry<K, V>() {
|
||||
private final Map.Entry<Key, V> en = it.next();
|
||||
|
||||
@SuppressWarnings("unchecked")
|
||||
@Override
|
||||
public K getKey() {
|
||||
return (K) en.getKey().get();
|
||||
}
|
||||
|
||||
@Override
|
||||
public V getValue() {
|
||||
return en.getValue();
|
||||
}
|
||||
|
||||
@Override
|
||||
public V setValue(V value) {
|
||||
Objects.requireNonNull(value);
|
||||
return en.setValue(value);
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
@Override
|
||||
public void remove() {
|
||||
it.remove();
|
||||
}
|
||||
};
|
||||
}
|
||||
};
|
||||
}
|
||||
}
|
||||
105
java/org/apache/tomcat/util/collections/SynchronizedQueue.java
Normal file
105
java/org/apache/tomcat/util/collections/SynchronizedQueue.java
Normal file
@@ -0,0 +1,105 @@
|
||||
/*
|
||||
* 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.tomcat.util.collections;
|
||||
|
||||
/**
|
||||
* This is intended as a (mostly) GC-free alternative to
|
||||
* {@link java.util.concurrent.ConcurrentLinkedQueue} when the requirement is to
|
||||
* create an unbounded queue with no requirement to shrink the queue. The aim is
|
||||
* to provide the bare minimum of required functionality as quickly as possible
|
||||
* with minimum garbage.
|
||||
*
|
||||
* @param <T> The type of object managed by this queue
|
||||
*/
|
||||
public class SynchronizedQueue<T> {
|
||||
|
||||
public static final int DEFAULT_SIZE = 128;
|
||||
|
||||
private Object[] queue;
|
||||
private int size;
|
||||
private int insert = 0;
|
||||
private int remove = 0;
|
||||
|
||||
public SynchronizedQueue() {
|
||||
this(DEFAULT_SIZE);
|
||||
}
|
||||
|
||||
public SynchronizedQueue(int initialSize) {
|
||||
queue = new Object[initialSize];
|
||||
size = initialSize;
|
||||
}
|
||||
|
||||
public synchronized boolean offer(T t) {
|
||||
queue[insert++] = t;
|
||||
|
||||
// Wrap
|
||||
if (insert == size) {
|
||||
insert = 0;
|
||||
}
|
||||
|
||||
if (insert == remove) {
|
||||
expand();
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
public synchronized T poll() {
|
||||
if (insert == remove) {
|
||||
// empty
|
||||
return null;
|
||||
}
|
||||
|
||||
@SuppressWarnings("unchecked")
|
||||
T result = (T) queue[remove];
|
||||
queue[remove] = null;
|
||||
remove++;
|
||||
|
||||
// Wrap
|
||||
if (remove == size) {
|
||||
remove = 0;
|
||||
}
|
||||
|
||||
return result;
|
||||
}
|
||||
|
||||
private void expand() {
|
||||
int newSize = size * 2;
|
||||
Object[] newQueue = new Object[newSize];
|
||||
|
||||
System.arraycopy(queue, insert, newQueue, 0, size - insert);
|
||||
System.arraycopy(queue, 0, newQueue, size - insert, insert);
|
||||
|
||||
insert = size;
|
||||
remove = 0;
|
||||
queue = newQueue;
|
||||
size = newSize;
|
||||
}
|
||||
|
||||
public synchronized int size() {
|
||||
int result = insert - remove;
|
||||
if (result < 0) {
|
||||
result += size;
|
||||
}
|
||||
return result;
|
||||
}
|
||||
|
||||
public synchronized void clear() {
|
||||
queue = new Object[size];
|
||||
insert = 0;
|
||||
remove = 0;
|
||||
}
|
||||
}
|
||||
105
java/org/apache/tomcat/util/collections/SynchronizedStack.java
Normal file
105
java/org/apache/tomcat/util/collections/SynchronizedStack.java
Normal file
@@ -0,0 +1,105 @@
|
||||
/*
|
||||
* 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.tomcat.util.collections;
|
||||
|
||||
/**
|
||||
* This is intended as a (mostly) GC-free alternative to
|
||||
* {@link java.util.concurrent.ConcurrentLinkedQueue} when the requirement is to
|
||||
* create a pool of re-usable objects with no requirement to shrink the pool.
|
||||
* The aim is to provide the bare minimum of required functionality as quickly
|
||||
* as possible with minimum garbage.
|
||||
*
|
||||
* @param <T> The type of object managed by this stack
|
||||
*/
|
||||
public class SynchronizedStack<T> {
|
||||
|
||||
public static final int DEFAULT_SIZE = 128;
|
||||
private static final int DEFAULT_LIMIT = -1;
|
||||
|
||||
private int size;
|
||||
private final int limit;
|
||||
|
||||
/*
|
||||
* Points to the next available object in the stack
|
||||
*/
|
||||
private int index = -1;
|
||||
|
||||
private Object[] stack;
|
||||
|
||||
|
||||
public SynchronizedStack() {
|
||||
this(DEFAULT_SIZE, DEFAULT_LIMIT);
|
||||
}
|
||||
|
||||
public SynchronizedStack(int size, int limit) {
|
||||
if (limit > -1 && size > limit) {
|
||||
this.size = limit;
|
||||
} else {
|
||||
this.size = size;
|
||||
}
|
||||
this.limit = limit;
|
||||
stack = new Object[size];
|
||||
}
|
||||
|
||||
|
||||
public synchronized boolean push(T obj) {
|
||||
index++;
|
||||
if (index == size) {
|
||||
if (limit == -1 || size < limit) {
|
||||
expand();
|
||||
} else {
|
||||
index--;
|
||||
return false;
|
||||
}
|
||||
}
|
||||
stack[index] = obj;
|
||||
return true;
|
||||
}
|
||||
|
||||
@SuppressWarnings("unchecked")
|
||||
public synchronized T pop() {
|
||||
if (index == -1) {
|
||||
return null;
|
||||
}
|
||||
T result = (T) stack[index];
|
||||
stack[index--] = null;
|
||||
return result;
|
||||
}
|
||||
|
||||
public synchronized void clear() {
|
||||
if (index > -1) {
|
||||
for (int i = 0; i < index + 1; i++) {
|
||||
stack[i] = null;
|
||||
}
|
||||
}
|
||||
index = -1;
|
||||
}
|
||||
|
||||
private void expand() {
|
||||
int newSize = size * 2;
|
||||
if (limit != -1 && newSize > limit) {
|
||||
newSize = limit;
|
||||
}
|
||||
Object[] newStack = new Object[newSize];
|
||||
System.arraycopy(stack, 0, newStack, 0, size);
|
||||
// This is the only point where garbage is created by throwing away the
|
||||
// old array. Note it is only the array, not the contents, that becomes
|
||||
// garbage.
|
||||
stack = newStack;
|
||||
size = newSize;
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user