/*
* Copyright 2014-2015 the original author or authors
*
* 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.wplatform.ddal.util;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.atomic.AtomicInteger;
import com.wplatform.ddal.value.CaseInsensitiveMap;
/**
* This class contains static methods to construct commonly used generic objects
* such as ArrayList.
*/
public class New {
/**
* Create a new ArrayList.
*
* @param <T> the type
* @return the object
*/
public static <T> ArrayList<T> arrayList() {
return new ArrayList<T>(4);
}
/**
* Create a new HashMap.
*
* @param <K> the key type
* @param <V> the value type
* @return the object
*/
public static <K, V> HashMap<K, V> hashMap() {
return new HashMap<K, V>();
}
/**
* Create a new HashSet.
*
* @param <T> the type
* @return the object
*/
public static <T> HashSet<T> hashSet() {
return new HashSet<T>();
}
/**
* Create a new ArrayList.
*
* @param <T> the type
* @param c the collection
* @return the object
*/
public static <T> ArrayList<T> arrayList(Collection<T> c) {
return new ArrayList<T>(c);
}
/**
* Create a new ArrayList.
*
* @param <T> the type
* @param initialCapacity the initial capacity
* @return the object
*/
public static <T> ArrayList<T> arrayList(int initialCapacity) {
return new ArrayList<T>(initialCapacity);
}
/**
* Create a new ArrayList.
*
* @param <T> the type
* @return the object
*/
public static <T> LinkedList<T> linkedList() {
return new LinkedList<T>();
}
/**
* Create a new CopyOnWriteArrayList.
*
* @param <T> the type
* @param initialCapacity the initial capacity
* @return the object
*/
public static <T> CopyOnWriteArrayList<T> copyOnWriteArrayList() {
return new CopyOnWriteArrayList<T>();
}
/**
* Create a new HashMap.
*
* @param <K> the key type
* @param <V> the value type
* @param initialCapacity the initial capacity
* @return the object
*/
public static <K, V> HashMap<K, V> hashMap(int initialCapacity) {
return new HashMap<K, V>(initialCapacity);
}
/**
* Create a new HashMap.
*
* @param <K> the key type
* @param <V> the value type
* @param initialCapacity the initial capacity
* @return the object
*/
public static <K, V> HashMap<K, V> hashMap(int initialCapacity, float loadFactor) {
return new HashMap<K, V>(initialCapacity, loadFactor);
}
/**
* Create a new LinkedHashMap.
*
* @param <K> the key type
* @param <V> the value type
* @param initialCapacity the initial capacity
* @return the object
*/
public static <K, V> LinkedHashMap<K, V> linkedHashMap() {
return new LinkedHashMap<K, V>();
}
/**
* Create a new LinkedHashMap.
*
* @param <K> the key type
* @param <V> the value type
* @param initialCapacity the initial capacity
* @return the object
*/
public static <K, V> LinkedHashMap<K, V> linkedHashMap(int initialCapacity) {
return new LinkedHashMap<K, V>(initialCapacity);
}
/**
* Create a new LinkedHashMap.
*
* @param initialCapacity
* @param loadFactor
* @return
*/
public static <K, V> LinkedHashMap<K, V> linkedHashMap(int initialCapacity, float loadFactor) {
return new LinkedHashMap<K, V>(initialCapacity);
}
/**
* Create a new ConcurrentHashMap.
*
* @param <K> the key type
* @param <V> the value type
* @param initialCapacity the initial capacity
* @return the object
*/
public static <K, V> ConcurrentHashMap<K, V> concurrentHashMap() {
return new ConcurrentHashMap<K, V>();
}
/**
* Create a new ConcurrentHashMap.
*
* @param <K> the key type
* @param <V> the value type
* @param initialCapacity the initial capacity
* @return the object
*/
public static <K, V> ConcurrentHashMap<K, V> concurrentHashMap(int initialCapacity) {
return new ConcurrentHashMap<K, V>(initialCapacity);
}
/**
* Create a new ConcurrentHashMap.
*
* @param initialCapacity
* @param loadFactor
* @return
*/
public static <K, V> ConcurrentHashMap<K, V> concurrentHashMap(int initialCapacity, float loadFactor) {
return new ConcurrentHashMap<K, V>(initialCapacity);
}
/**
* Create a new CaseInsensitiveMap.
*
* @param <K> the key type
* @param <V> the value type
* @param initialCapacity the initial capacity
* @return the object
*/
public static <K, V> CaseInsensitiveMap<V> caseInsensitiveMap() {
return new CaseInsensitiveMap<V>();
}
/**
* Create a new HashSet.
*
* @param initialCapacity
* @return
*/
public static <T> HashSet<T> hashSet(int initialCapacity) {
return new HashSet<T>(initialCapacity);
}
/**
* Create a new HashSet.
*
* @param initialCapacity
* @param loadFactor
* @return
*/
public static <T> HashSet<T> hashSet(int initialCapacity, float loadFactor) {
return new HashSet<T>(initialCapacity, loadFactor);
}
/**
* Create a new LinkedHashSet.
*
* @param <T> the type
* @return the object
*/
public static <T> HashSet<T> linkedHashSet() {
return new LinkedHashSet<T>();
}
/**
* Create a new CopyOnWriteArraySet.
*
* @param <T> the type
* @return the object
*/
public static <T> CopyOnWriteArraySet<T> copyOnWriteArraySet() {
return new CopyOnWriteArraySet<T>();
}
/**
* Create a new CopyOnWriteArraySet.
*
* @param <T> the type
* @return the object
*/
public static ThreadFactory customThreadFactory(String namePrefix) {
return new CustomThreadFactory(namePrefix);
}
private static final class CustomThreadFactory implements ThreadFactory {
private final String prefix;
private final boolean daemon;
private final ThreadGroup group;
private final AtomicInteger index = new AtomicInteger(1);
public CustomThreadFactory(String prefix) {
this(prefix, false);
}
private CustomThreadFactory(String prefix, boolean daemon) {
SecurityManager sm = System.getSecurityManager();
group = (sm != null) ? sm.getThreadGroup()
: Thread.currentThread().getThreadGroup();
this.prefix = prefix;
this.daemon = daemon;
}
@Override
public Thread newThread(Runnable r) {
String name = prefix + "_" + index.getAndIncrement();
Thread t = new Thread(group, r, name);
t.setDaemon(daemon);
if (t.getPriority() != Thread.NORM_PRIORITY) {
t.setPriority(Thread.NORM_PRIORITY);
}
return t;
}
}
}