com.signalfx.shaded.jetty.util.IncludeExcludeSet Maven / Gradle / Ivy
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//
// ========================================================================
// Copyright (c) 1995-2022 Mort Bay Consulting Pty Ltd and others.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package com.signalfx.shaded.jetty.util;
import java.util.HashSet;
import java.util.Objects;
import java.util.Set;
import java.util.function.Predicate;
/**
* Utility class to maintain a set of inclusions and exclusions.
* Maintains a set of included and excluded elements. The method {@link #test(Object)}
* will return true IFF the passed object is not in the excluded set AND ( either the
* included set is empty OR the object is in the included set)
*
The type of the underlying {@link Set} used may be passed into the
* constructor, so special sets like Servlet PathMap may be used.
*
*
* @param The type of element of the set (often a pattern)
* @param The type of the instance passed to the predicate
*/
public class IncludeExcludeSet implements Predicate
{
private final Set _includes;
private final Predicate _includePredicate;
private final Set _excludes;
private final Predicate _excludePredicate;
private static class SetContainsPredicate implements Predicate
{
private final Set set;
public SetContainsPredicate(Set set)
{
this.set = set;
}
@Override
public boolean test(T item)
{
return set.contains(item);
}
@Override
public String toString()
{
return "CONTAINS";
}
}
/**
* Default constructor over {@link HashSet}
*/
public IncludeExcludeSet()
{
this(HashSet.class);
}
/**
* Construct an IncludeExclude.
*
* @param setClass The type of {@link Set} to using internally to hold patterns. Two instances will be created.
* one for include patterns and one for exclude patters. If the class is also a {@link Predicate},
* then it is also used as the item test for the set, otherwise a {@link SetContainsPredicate} instance
* is created.
* @param The type of a set to use as the backing store
*/
public > IncludeExcludeSet(Class setClass)
{
try
{
_includes = setClass.getDeclaredConstructor().newInstance();
_excludes = setClass.getDeclaredConstructor().newInstance();
if (_includes instanceof Predicate)
{
_includePredicate = (Predicate)_includes;
}
else
{
_includePredicate = new SetContainsPredicate(_includes);
}
if (_excludes instanceof Predicate)
{
_excludePredicate = (Predicate
)_excludes;
}
else
{
_excludePredicate = new SetContainsPredicate(_excludes);
}
}
catch (RuntimeException e)
{
throw e;
}
catch (Exception e)
{
throw new RuntimeException(e);
}
}
/**
* Construct an IncludeExclude
*
* @param includeSet the Set of items that represent the included space
* @param includePredicate the Predicate for included item testing (null for simple {@link Set#contains(Object)} test)
* @param excludeSet the Set of items that represent the excluded space
* @param excludePredicate the Predicate for excluded item testing (null for simple {@link Set#contains(Object)} test)
* @param The type of a set to use as the backing store
*/
public > IncludeExcludeSet(Set includeSet, Predicate includePredicate, Set excludeSet, Predicate excludePredicate)
{
Objects.requireNonNull(includeSet, "Include Set");
Objects.requireNonNull(includePredicate, "Include Predicate");
Objects.requireNonNull(excludeSet, "Exclude Set");
Objects.requireNonNull(excludePredicate, "Exclude Predicate");
_includes = includeSet;
_includePredicate = includePredicate;
_excludes = excludeSet;
_excludePredicate = excludePredicate;
}
public void include(T element)
{
_includes.add(element);
}
public void include(T... element)
{
for (T e : element)
{
_includes.add(e);
}
}
public void exclude(T element)
{
_excludes.add(element);
}
public void exclude(T... element)
{
for (T e : element)
{
_excludes.add(e);
}
}
@Deprecated
public boolean matches(P t)
{
return test(t);
}
@Override
public boolean test(P t)
{
if (!_includes.isEmpty() && !_includePredicate.test(t))
return false;
return !_excludePredicate.test(t);
}
/**
* Test Included and not Excluded
*
* @param item The item to test
* @return Boolean.TRUE if item is included, Boolean.FALSE if item is excluded or null if neither
*/
public Boolean isIncludedAndNotExcluded(P item)
{
if (_excludePredicate.test(item))
return Boolean.FALSE;
if (_includePredicate.test(item))
return Boolean.TRUE;
return null;
}
public boolean hasIncludes()
{
return !_includes.isEmpty();
}
public boolean hasExcludes()
{
return !_excludes.isEmpty();
}
public int size()
{
return _includes.size() + _excludes.size();
}
public Set getIncluded()
{
return _includes;
}
public Set getExcluded()
{
return _excludes;
}
public void clear()
{
_includes.clear();
_excludes.clear();
}
@Override
public String toString()
{
return String.format("%s@%x{i=%s,ip=%s,e=%s,ep=%s}", this.getClass().getSimpleName(), hashCode(),
_includes,
_includePredicate == _includes ? "SELF" : _includePredicate,
_excludes,
_excludePredicate == _excludes ? "SELF" : _excludePredicate);
}
public boolean isEmpty()
{
return _includes.isEmpty() && _excludes.isEmpty();
}
/**
* Match items in combined IncludeExcludeSets.
* @param item1 The item to match against set1
* @param set1 A IncludeExcludeSet to match item1 against
* @param item2 The item to match against set2
* @param set2 A IncludeExcludeSet to match item2 against
* @param The type of item1
* @param The type of item2
* @return True IFF
* - Neither item is excluded from their respective sets
* - Both sets have no includes OR at least one of the items is included in its respective set
*
*/
public static boolean matchCombined(T1 item1, IncludeExcludeSet set1, T2 item2, IncludeExcludeSet set2)
{
Boolean match1 = set1.isIncludedAndNotExcluded(item1);
Boolean match2 = set2.isIncludedAndNotExcluded(item2);
// if we are excluded from either set, then we do not match
if (Boolean.FALSE.equals(match1) || Boolean.FALSE.equals(match2))
return false;
// If either set has any includes, then we must be included by one of them
if (set1.hasIncludes() || set2.hasIncludes())
return Boolean.TRUE.equals(match1) || Boolean.TRUE.equals(match2);
// If not excluded and no includes, then we match
return true;
}
}