org.osgl.util.SetBase Maven / Gradle / Ivy
package org.osgl.util;
/*-
* #%L
* Java Tool
* %%
* Copyright (C) 2014 - 2017 OSGL (Open Source General Library)
* %%
* 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.
* #L%
*/
import org.osgl.$;
import org.osgl.exception.NotAppliedException;
import java.util.AbstractSet;
import java.util.Collection;
import java.util.EnumSet;
public abstract class SetBase extends AbstractSet implements C.Set {
@Override
public C.Set parallel() {
setFeature(C.Feature.PARALLEL);
return this;
}
@Override
public C.Set sequential() {
unsetFeature(C.Feature.PARALLEL);
return this;
}
@Override
public C.Set lazy() {
setFeature(C.Feature.LAZY);
return this;
}
@Override
public C.Set eager() {
unsetFeature(C.Feature.LAZY);
return this;
}
@Override
public C.Set filter($.Function predicate) {
boolean immutable = isImmutable();
int sz = size();
// TODO: handle lazy filter
if (immutable) {
if (0 == sz) {
return Nil.set();
}
ListBuilder lb = new ListBuilder(sz);
forEach($.visitor($.predicate(predicate).ifThen(C.F.addTo(lb))));
return lb.toSet();
} else {
if (0 == sz) {
return C.newSet();
}
C.Set set = C.newSet();
forEach($.visitor($.predicate(predicate).ifThen(C.F.addTo(set))));
return set;
}
}
@Override
public SetBase accept($.Visitor visitor) {
return forEach(visitor);
}
@Override
public C.Traversable map($.Function mapper) {
boolean immutable = isImmutable();
int sz = size();
if (immutable) {
if (0 == sz) {
return Nil.set();
}
ListBuilder lb = new ListBuilder<>(sz);
forEach($.visitor($.f1(mapper).andThen(C.F.addTo(lb))));
return lb.toList();
} else {
if (0 == sz) {
return C.newSet();
}
C.List l = C.newSizedList(sz);
forEach($.visitor($.f1(mapper).andThen(C.F.addTo(l))));
return l;
}
}
@Override
public C.Traversable flatMap($.Function> mapper) {
C.List list = C.newList();
for (T t : this) {
Iterable iterable = mapper.apply(t);
list.addAll(C.list(iterable));
}
return list;
}
@Override
public C.Traversable collect(String path) {
C.List list = C.newList();
for (T t : this) {
list.add((R) $.getProperty(t, path));
}
return list;
}
@Override
public R reduce(R identity, $.Func2 accumulator) {
return null;
}
@Override
public $.Option reduce($.Func2 accumulator) {
return null;
}
@Override
public boolean allMatch($.Function predicate) {
return false;
}
@Override
public boolean anyMatch($.Function predicate) {
return false;
}
@Override
public boolean noneMatch($.Function predicate) {
return false;
}
@Override
public $.Option findOne($.Function predicate) {
return null;
}
// utilities
protected final boolean isLazy() {
return is(C.Feature.LAZY);
}
protected final boolean isImmutable() {
return is(C.Feature.IMMUTABLE);
}
protected final boolean isReadOnly() {
return is(C.Feature.READONLY);
}
protected final boolean isMutable() {
return !isImmutable() && !isReadOnly();
}
/**
* Sub class could override this method to implement iterating in parallel.
*
* The iterating support partial function visitor by ignoring the
* {@link org.osgl.exception.NotAppliedException} thrown out by visitor's apply
* method call
*
* @param visitor the visitor
* @throws $.Break if visitor needs to terminate the iteration
*/
public SetBase forEach($.Visitor visitor) throws $.Break {
for (T t : this) {
try {
visitor.apply(t);
} catch (NotAppliedException e) {
// ignore
}
}
return this;
}
@Override
public SetBase each($.Visitor visitor) {
return forEach(visitor);
}
@Override
public C.Set onlyIn(Collection col) {
C.Set others = C.newSet(col);
others.removeAll(this);
if (isImmutable()) {
return ImmutableSet.of(others);
}
return others;
}
@Override
public C.Set withIn(Collection col) {
C.Set others = C.newSet(col);
others.retainAll(this);
if (isImmutable()) {
return ImmutableSet.of(others);
}
return others;
}
@Override
public C.Set without(Collection col) {
C.Set copy = C.newSet(this);
copy.removeAll(col);
if (isImmutable()) {
return ImmutableSet.of(copy);
}
return copy;
}
@Override
public C.Set with(Collection col) {
C.Set copy = C.newSet(this);
copy.addAll(col);
if (isImmutable()) {
return ImmutableSet.of(copy);
}
return copy;
}
@Override
public C.Set with(T element) {
C.Set copy = C.newSet(this);
copy.add(element);
return copy;
}
@Override
public C.Set with(T element, T... elements) {
C.Set copy = C.newSet(this);
copy.add(element);
copy.addAll(C.listOf(elements));
return copy;
}
@Override
public C.Set without(T element) {
return null;
}
@Override
public C.Set without(T element, T... elements) {
return null;
}
// --- Featured methods
volatile private EnumSet features_;
protected final EnumSet features_() {
if (null == features_) {
synchronized (this) {
if (null == features_) {
features_ = initFeatures();
assert(null != features_);
}
}
}
return features_;
}
/**
* Sub class should override this method to provide initial feature
* set for the feature based instance
*
* @return the initial feature set configuration
*/
abstract protected EnumSet initFeatures();
@Override
public final EnumSet features() {
return EnumSet.copyOf(features_());
}
@Override
public final boolean is(C.Feature feature) {
return features_().contains(feature);
}
protected SetBase setFeature(C.Feature feature) {
features_().add(feature);
return this;
}
protected SetBase unsetFeature(C.Feature feature) {
features_().remove(feature);
return this;
}
// --- eof Featured methods
}