io.netty.handler.codec.HeadersUtils Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* Copyright 2015 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty.handler.codec;
import java.util.AbstractCollection;
import java.util.AbstractList;
import java.util.Iterator;
import java.util.List;
import java.util.Map.Entry;
import java.util.Set;
import static io.netty.util.internal.ObjectUtil.checkNotNull;
/**
* Provides utility methods related to {@link Headers}.
*/
public final class HeadersUtils {
private HeadersUtils() {
}
/**
* {@link Headers#get(Object)} and convert each element of {@link List} to a {@link String}.
* @param name the name of the header to retrieve
* @return a {@link List} of header values or an empty {@link List} if no values are found.
*/
public static List getAllAsString(Headers headers, K name) {
final List allNames = headers.getAll(name);
return new AbstractList() {
@Override
public String get(int index) {
V value = allNames.get(index);
return value != null ? value.toString() : null;
}
@Override
public int size() {
return allNames.size();
}
};
}
/**
* {@link Headers#get(Object)} and convert the result to a {@link String}.
* @param headers the headers to get the {@code name} from
* @param name the name of the header to retrieve
* @return the first header value if the header is found. {@code null} if there's no such entry.
*/
public static String getAsString(Headers headers, K name) {
V orig = headers.get(name);
return orig != null ? orig.toString() : null;
}
/**
* {@link Headers#iterator()} which converts each {@link Entry}'s key and value to a {@link String}.
*/
public static Iterator> iteratorAsString(
Iterable> headers) {
return new StringEntryIterator(headers.iterator());
}
/**
* Helper for implementing toString for {@link DefaultHeaders} and wrappers such as DefaultHttpHeaders.
* @param headersClass the class of headers
* @param headersIt the iterator on the actual headers
* @param size the size of the iterator
* @return a String representation of the headers
*/
public static String toString(Class headersClass, Iterator> headersIt, int size) {
String simpleName = headersClass.getSimpleName();
if (size == 0) {
return simpleName + "[]";
} else {
// original capacity assumes 20 chars per headers
StringBuilder sb = new StringBuilder(simpleName.length() + 2 + size * 20)
.append(simpleName)
.append('[');
while (headersIt.hasNext()) {
Entry header = headersIt.next();
sb.append(header.getKey()).append(": ").append(header.getValue()).append(", ");
}
sb.setLength(sb.length() - 2);
return sb.append(']').toString();
}
}
/**
* {@link Headers#names()} and convert each element of {@link Set} to a {@link String}.
* @param headers the headers to get the names from
* @return a {@link Set} of header values or an empty {@link Set} if no values are found.
*/
public static Set namesAsString(Headers headers) {
return new DelegatingNameSet(headers);
}
private static final class StringEntryIterator implements Iterator> {
private final Iterator> iter;
StringEntryIterator(Iterator> iter) {
this.iter = iter;
}
@Override
public boolean hasNext() {
return iter.hasNext();
}
@Override
public Entry next() {
return new StringEntry(iter.next());
}
@Override
public void remove() {
iter.remove();
}
}
private static final class StringEntry implements Entry {
private final Entry entry;
private String name;
private String value;
StringEntry(Entry entry) {
this.entry = entry;
}
@Override
public String getKey() {
if (name == null) {
name = entry.getKey().toString();
}
return name;
}
@Override
public String getValue() {
if (value == null && entry.getValue() != null) {
value = entry.getValue().toString();
}
return value;
}
@Override
public String setValue(String value) {
String old = getValue();
entry.setValue(value);
return old;
}
@Override
public String toString() {
return entry.toString();
}
}
private static final class StringIterator implements Iterator {
private final Iterator iter;
StringIterator(Iterator iter) {
this.iter = iter;
}
@Override
public boolean hasNext() {
return iter.hasNext();
}
@Override
public String next() {
T next = iter.next();
return next != null ? next.toString() : null;
}
@Override
public void remove() {
iter.remove();
}
}
private static final class DelegatingNameSet extends AbstractCollection implements Set {
private final Headers headers;
DelegatingNameSet(Headers headers) {
this.headers = checkNotNull(headers, "headers");
}
@Override
public int size() {
return headers.names().size();
}
@Override
public boolean isEmpty() {
return headers.isEmpty();
}
@Override
public boolean contains(Object o) {
return headers.contains(o.toString());
}
@Override
public Iterator iterator() {
return new StringIterator(headers.names().iterator());
}
}
}