io.netty.util.DomainNameMapping Maven / Gradle / Ivy
/*
* Copyright 2014 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:
*
* 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 io.netty.util;
import io.netty.util.internal.StringUtil;
import java.net.IDN;
import java.util.LinkedHashMap;
import java.util.Locale;
import java.util.Map;
import static io.netty.util.internal.ObjectUtil.checkNotNull;
import static io.netty.util.internal.StringUtil.commonSuffixOfLength;
/**
* Maps a domain name to its associated value object.
*
* DNS wildcard is supported as hostname, so you can use {@code *.netty.io} to match both {@code netty.io}
* and {@code downloads.netty.io}.
*
*/
public class DomainNameMapping implements Mapping {
final V defaultValue;
private final Map map;
/**
* Creates a default, order-sensitive mapping. If your hostnames are in conflict, the mapping
* will choose the one you add first.
*
* @param defaultValue the default value for {@link #map(String)} to return when nothing matches the input
* @deprecated use {@link DomainMappingBuilder} to create and fill the mapping instead
*/
@Deprecated
public DomainNameMapping(V defaultValue) {
this(4, defaultValue);
}
/**
* Creates a default, order-sensitive mapping. If your hostnames are in conflict, the mapping
* will choose the one you add first.
*
* @param initialCapacity initial capacity for the internal map
* @param defaultValue the default value for {@link #map(String)} to return when nothing matches the input
* @deprecated use {@link DomainMappingBuilder} to create and fill the mapping instead
*/
@Deprecated
public DomainNameMapping(int initialCapacity, V defaultValue) {
this(new LinkedHashMap(initialCapacity), defaultValue);
}
DomainNameMapping(Map map, V defaultValue) {
this.defaultValue = checkNotNull(defaultValue, "defaultValue");
this.map = map;
}
/**
* Adds a mapping that maps the specified (optionally wildcard) host name to the specified output value.
*
* DNS wildcard is supported as hostname.
* For example, you can use {@code *.netty.io} to match {@code netty.io} and {@code downloads.netty.io}.
*
*
* @param hostname the host name (optionally wildcard)
* @param output the output value that will be returned by {@link #map(String)} when the specified host name
* matches the specified input host name
* @deprecated use {@link DomainMappingBuilder} to create and fill the mapping instead
*/
@Deprecated
public DomainNameMapping add(String hostname, V output) {
map.put(normalizeHostname(checkNotNull(hostname, "hostname")), checkNotNull(output, "output"));
return this;
}
/**
* Simple function to match DNS wildcard.
*/
static boolean matches(String template, String hostName) {
if (template.startsWith("*.")) {
return template.regionMatches(2, hostName, 0, hostName.length())
|| commonSuffixOfLength(hostName, template, template.length() - 1);
}
return template.equals(hostName);
}
/**
* IDNA ASCII conversion and case normalization
*/
static String normalizeHostname(String hostname) {
if (needsNormalization(hostname)) {
hostname = IDN.toASCII(hostname, IDN.ALLOW_UNASSIGNED);
}
return hostname.toLowerCase(Locale.US);
}
private static boolean needsNormalization(String hostname) {
final int length = hostname.length();
for (int i = 0; i < length; i++) {
int c = hostname.charAt(i);
if (c > 0x7F) {
return true;
}
}
return false;
}
@Override
public V map(String hostname) {
if (hostname != null) {
hostname = normalizeHostname(hostname);
for (Map.Entry entry : map.entrySet()) {
if (matches(entry.getKey(), hostname)) {
return entry.getValue();
}
}
}
return defaultValue;
}
@Override
public String toString() {
return StringUtil.simpleClassName(this) + "(default: " + defaultValue + ", map: " + map + ')';
}
}