HeaderValuesMap.java
/*
* 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.tiles.request.collection;
import org.apache.tiles.request.attribute.EnumeratedValuesExtractor;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;
import static org.apache.tiles.request.collection.CollectionUtil.enumerationSize;
import static org.apache.tiles.request.collection.CollectionUtil.key;
/**
* Exposes an {@link EnumeratedValuesExtractor} object as a read-only map.
*/
public class HeaderValuesMap implements Map<String, String[]> {
/**
* The request.
*/
private final EnumeratedValuesExtractor request;
/**
* Constructor.
*
* @param request The request object to use.
*/
public HeaderValuesMap(EnumeratedValuesExtractor request) {
this.request = request;
}
/**
* {@inheritDoc}
*/
public void clear() {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc}
*/
public boolean containsKey(Object key) {
return (request.getValue(key(key)) != null);
}
/**
* {@inheritDoc}
*/
public boolean containsValue(Object value) {
if (!(value instanceof String[])) {
return (false);
}
String[] test = (String[]) value;
Enumeration<String> names = request.getKeys();
while (names.hasMoreElements()) {
String name = names.nextElement();
if (compareHeaders(name, array2set(test))) {
return true;
}
}
return false;
}
/**
* {@inheritDoc}
*/
public Set<Entry<String, String[]>> entrySet() {
return new HeadersEntrySet();
}
/**
* {@inheritDoc}
*/
@Override
public boolean equals(Object obj) {
if (obj == null) {
return false;
}
if (!(obj instanceof HeaderValuesMap)) {
return false;
}
EnumeratedValuesExtractor otherRequest = ((HeaderValuesMap) obj).request;
boolean retValue = true;
for (Enumeration<String> attribs = request.getKeys(); attribs.hasMoreElements() && retValue; ) {
String parameterName = attribs.nextElement();
Set<String> valueSet = enumeration2set(otherRequest.getValues(parameterName));
retValue = compareHeaders(parameterName, valueSet);
}
return retValue;
}
/**
* {@inheritDoc}
*/
public String[] get(Object key) {
return getHeaderValues(key(key));
}
/**
* {@inheritDoc}
*/
@Override
public int hashCode() {
int retValue = 0;
for (Enumeration<String> attribs = request.getKeys(); attribs
.hasMoreElements(); ) {
String parameterName = attribs.nextElement();
Enumeration<String> values = request.getValues(parameterName);
int valueHash = 0;
while (values.hasMoreElements()) {
valueHash += values.nextElement().hashCode();
}
retValue += parameterName.hashCode() ^ valueHash;
}
return retValue;
}
/**
* {@inheritDoc}
*/
public boolean isEmpty() {
return !request.getKeys().hasMoreElements();
}
/**
* {@inheritDoc}
*/
public Set<String> keySet() {
return new KeySet(request);
}
/**
* {@inheritDoc}
*/
public String[] put(String key, String[] value) {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc}
*/
public void putAll(Map<? extends String, ? extends String[]> map) {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc}
*/
public String[] remove(Object key) {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc}
*/
public int size() {
return enumerationSize(request.getKeys());
}
/**
* {@inheritDoc}
*/
public Collection<String[]> values() {
return new HeaderValuesCollection();
}
/**
* Extracts values enumeration of an attribute and returns the corresponding array of values.
*
* @param key The key of the attribute.
* @return The values of the attribute.
*/
private String[] getHeaderValues(String key) {
List<String> list = new ArrayList<>();
Enumeration<String> values = request.getValues(key);
while (values.hasMoreElements()) {
list.add(values.nextElement());
}
return list.toArray(new String[0]);
}
/**
* Converts the content of a string enumeration to an array of strings.
*
* @param enumeration The enumeration to convert.
* @return The corresponding array.
*/
private Set<String> enumeration2set(Enumeration<String> enumeration) {
Set<String> retValue = new HashSet<>();
while (enumeration.hasMoreElements()) {
retValue.add(enumeration.nextElement());
}
return retValue;
}
/**
* Transforms a string array in a string set.
*
* @param valueArray The array to convert.
* @return The corresponding set.
*/
private Set<String> array2set(String[] valueArray) {
Set<String> values = new HashSet<>();
Collections.addAll(values, valueArray);
return values;
}
/**
* Checks if values of a header attribute are the same as the one passed in
* the set.
*
* @param name The name of the header.
* @param testSet The set of values it must contain.
* @return <code>true</code> if all the values, and only them, are present
* in the header values.
*/
private boolean compareHeaders(String name, Set<String> testSet) {
Enumeration<String> values = request.getValues(name);
boolean matched = true;
while (values.hasMoreElements() && matched) {
String currentValue = values.nextElement();
matched = testSet.remove(currentValue);
}
matched = matched && testSet.isEmpty();
return matched;
}
/**
* Entry set implementation for {@link HeaderValuesMap}.
*/
private class HeadersEntrySet implements Set<Entry<String, String[]>> {
@Override
public boolean add(Entry<String, String[]> e) {
throw new UnsupportedOperationException();
}
@Override
public boolean addAll(
Collection<? extends Entry<String, String[]>> c) {
throw new UnsupportedOperationException();
}
@Override
public void clear() {
throw new UnsupportedOperationException();
}
@SuppressWarnings("unchecked")
@Override
public boolean contains(Object o) {
return containsEntry((Entry<String, String[]>) o);
}
@SuppressWarnings("unchecked")
@Override
public boolean containsAll(Collection<?> c) {
Collection<Entry<String, String[]>> realCollection =
(Collection<Entry<String, String[]>>) c;
for (Entry<String, String[]> entry : realCollection) {
if (!containsEntry(entry)) {
return false;
}
}
return true;
}
@Override
public boolean isEmpty() {
return HeaderValuesMap.this.isEmpty();
}
@Override
public Iterator<Entry<String, String[]>> iterator() {
return new HeadersEntrySetIterator();
}
@Override
public boolean remove(Object o) {
throw new UnsupportedOperationException();
}
@Override
public boolean removeAll(Collection<?> c) {
throw new UnsupportedOperationException();
}
@Override
public boolean retainAll(Collection<?> c) {
throw new UnsupportedOperationException();
}
@Override
public int size() {
return HeaderValuesMap.this.size();
}
@Override
public Object[] toArray() {
return toList().toArray();
}
@Override
public <T> T[] toArray(T[] a) {
return toList().toArray(a);
}
/**
* Checks whether the given entry is present in the headers.
*
* @param entry The entry to check.
* @return <code></code> if the key and the values of the entry are present.
*/
private boolean containsEntry(Entry<String, String[]> entry) {
Enumeration<String> entryValues = request.getValues(key(entry.getKey()));
String[] valueArray = entry.getValue();
Set<String> values = array2set(valueArray);
while (entryValues.hasMoreElements()) {
if (!values.remove(entryValues.nextElement())) {
return false;
}
}
return values.isEmpty();
}
/**
* Turns this entry set into a list.
*
* @return The collection, turned into a list.
*/
private List<Entry<String, String[]>> toList() {
List<Entry<String, String[]>> entries = new ArrayList<>();
Enumeration<String> names = request.getKeys();
while (names.hasMoreElements()) {
entries.add(extractNextEntry(names));
}
return entries;
}
/**
* Returns the next entry, by getting the next element in the given enumeration.
*
* @param names The enumeration to get the next name from..
* @return The next map entry.
*/
private MapEntry<String, String[]> extractNextEntry(Enumeration<String> names) {
String name = names.nextElement();
return new MapEntryArrayValues<>(name, getHeaderValues(name), false);
}
/**
* Iterates {@link HeadersEntrySet} elements.
*/
private class HeadersEntrySetIterator implements Iterator<Entry<String, String[]>> {
/**
* The enumeration to use.
*/
private final Enumeration<String> namesEnumeration = request.getKeys();
@Override
public boolean hasNext() {
return namesEnumeration.hasMoreElements();
}
@Override
public Entry<String, String[]> next() {
if (namesEnumeration.hasMoreElements()) {
return extractNextEntry(namesEnumeration);
}
throw new NoSuchElementException();
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
}
}
/**
* It is a collection of all values of the header. Each element is an array
* of values of a single header.
*/
private class HeaderValuesCollection implements Collection<String[]> {
@Override
public boolean add(String[] e) {
throw new UnsupportedOperationException();
}
@Override
public boolean addAll(Collection<? extends String[]> c) {
throw new UnsupportedOperationException();
}
@Override
public void clear() {
throw new UnsupportedOperationException();
}
@Override
public boolean contains(Object o) {
return containsValue(o);
}
@SuppressWarnings("unchecked")
@Override
public boolean containsAll(Collection<?> c) {
Collection<String[]> realCollection = (Collection<String[]>) c;
for (String[] value : realCollection) {
if (!containsValue(value)) {
return false;
}
}
return true;
}
@Override
public boolean isEmpty() {
return HeaderValuesMap.this.isEmpty();
}
@Override
public Iterator<String[]> iterator() {
return new HeaderValuesCollectionIterator();
}
@Override
public boolean remove(Object o) {
throw new UnsupportedOperationException();
}
@Override
public boolean removeAll(Collection<?> c) {
throw new UnsupportedOperationException();
}
@Override
public boolean retainAll(Collection<?> c) {
throw new UnsupportedOperationException();
}
@Override
public int size() {
return HeaderValuesMap.this.size();
}
@Override
public Object[] toArray() {
return toList().toArray();
}
@Override
public <T> T[] toArray(T[] a) {
return toList().toArray(a);
}
/**
* Turns this collection into a list.
*
* @return The list.
*/
private List<String[]> toList() {
List<String[]> entries = new ArrayList<>();
Enumeration<String> names = request.getKeys();
while (names.hasMoreElements()) {
entries.add(enumeration2array(request.getValues(names.nextElement())));
}
return entries;
}
/**
* Converts the content of a string enumeration to an array of strings.
*
* @param enumeration The enumeration to convert.
* @return The corresponding array.
*/
private String[] enumeration2array(Enumeration<String> enumeration) {
List<String> list1 = new ArrayList<>();
while (enumeration.hasMoreElements()) {
list1.add(enumeration.nextElement());
}
return list1.toArray(new String[0]);
}
/**
* Iterates elements of {@link HeaderValuesCollection}.
*/
private class HeaderValuesCollectionIterator implements Iterator<String[]> {
/**
* The enumeration of the name of header attributes.
*/
private final Enumeration<String> namesEnumeration = request.getKeys();
@Override
public boolean hasNext() {
return namesEnumeration.hasMoreElements();
}
@Override
public String[] next() {
if (namesEnumeration.hasMoreElements()) {
return enumeration2array(request.getValues(namesEnumeration.nextElement()));
}
throw new NoSuchElementException();
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
}
}
}