com.google.thirdparty.publicsuffix.TrieParser 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 (C) 2008 The Guava Authors
*
* 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.
*/
package com.google.thirdparty.publicsuffix;
import static com.google.common.collect.Queues.newArrayDeque;
import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Joiner;
import com.google.common.collect.ImmutableMap;
import java.util.Deque;
/** Parser for a map of reversed domain names stored as a serialized radix tree. */
@GwtCompatible
final class TrieParser {
private static final Joiner DIRECT_JOINER = Joiner.on("");
/**
* Parses a serialized trie representation of a map of reversed public suffixes into an immutable
* map of public suffixes. The encoded trie string may be broken into multiple chunks to avoid the
* 64k limit on string literal size. In-memory strings can be much larger (2G).
*/
static ImmutableMap parseTrie(CharSequence... encodedChunks) {
String encoded = DIRECT_JOINER.join(encodedChunks);
return parseFullString(encoded);
}
@VisibleForTesting
static ImmutableMap parseFullString(String encoded) {
ImmutableMap.Builder builder = ImmutableMap.builder();
int encodedLen = encoded.length();
int idx = 0;
while (idx < encodedLen) {
idx += doParseTrieToBuilder(newArrayDeque(), encoded, idx, builder);
}
return builder.buildOrThrow();
}
/**
* Parses a trie node and returns the number of characters consumed.
*
* @param stack The prefixes that precede the characters represented by this node. Each entry of
* the stack is in reverse order.
* @param encoded The serialized trie.
* @param start An index in the encoded serialized trie to begin reading characters from.
* @param builder A map builder to which all entries will be added.
* @return The number of characters consumed from {@code encoded}.
*/
private static int doParseTrieToBuilder(
Deque stack,
CharSequence encoded,
int start,
ImmutableMap.Builder builder) {
int encodedLen = encoded.length();
int idx = start;
char c = '\0';
// Read all the characters for this node.
for (; idx < encodedLen; idx++) {
c = encoded.charAt(idx);
if (c == '&' || c == '?' || c == '!' || c == ':' || c == ',') {
break;
}
}
stack.push(reverse(encoded.subSequence(start, idx)));
if (c == '!' || c == '?' || c == ':' || c == ',') {
// '!' represents an interior node that represents a REGISTRY entry in the map.
// '?' represents a leaf node, which represents a REGISTRY entry in map.
// ':' represents an interior node that represents a private entry in the map
// ',' represents a leaf node, which represents a private entry in the map.
String domain = DIRECT_JOINER.join(stack);
if (domain.length() > 0) {
builder.put(domain, PublicSuffixType.fromCode(c));
}
}
idx++;
if (c != '?' && c != ',') {
while (idx < encodedLen) {
// Read all the children
idx += doParseTrieToBuilder(stack, encoded, idx, builder);
if (encoded.charAt(idx) == '?' || encoded.charAt(idx) == ',') {
// An extra '?' or ',' after a child node indicates the end of all children of this node.
idx++;
break;
}
}
}
stack.pop();
return idx - start;
}
private static CharSequence reverse(CharSequence s) {
return new StringBuilder(s).reverse();
}
}