ai.platon.pulsar.common.SuffixStringMatcher Maven / Gradle / Ivy
/**
* 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 ai.platon.pulsar.common;
import java.util.Collection;
import java.util.Iterator;
/**
* A class for efficiently matching Strings against a set of
* suffixes. Zero-length Strings are ignored.
*
* @author vincent
* @version $Id: $Id
*/
public class SuffixStringMatcher extends TrieStringMatcher {
/**
* Creates a new PrefixStringMatcher which will match
* Strings with any suffix in the supplied array.
*
* @param suffixes an array of {@link java.lang.String} objects.
*/
public SuffixStringMatcher(String[] suffixes) {
super();
for (int i = 0; i < suffixes.length; i++)
addPatternBackward(suffixes[i]);
}
/**
* Creates a new PrefixStringMatcher which will match
* Strings with any suffix in the supplied
* Collection
*
* @param suffixes a {@link java.util.Collection} object.
*/
public SuffixStringMatcher(Collection suffixes) {
super();
Iterator iter = suffixes.iterator();
while (iter.hasNext())
addPatternBackward(iter.next());
}
/**
* main.
*
* @param argv an array of {@link java.lang.String} objects.
*/
public static final void main(String[] argv) {
SuffixStringMatcher matcher = new SuffixStringMatcher(new String[]{"a",
"abcd", "bcd", "bcdefg", "defg", "aac", "baz", "foo", "foobar"});
String[] tests = {"a", "ac", "abcd", "abcdefg", "apple", "aa", "aac",
"aaccca", "abaz", "baz", "bazooka", "fo", "foobar", "kite",};
for (int i = 0; i < tests.length; i++) {
System.out.println("testing: " + tests[i]);
System.out.println(" matches: " + matcher.matches(tests[i]));
System.out.println(" shortest: " + matcher.shortestMatch(tests[i]));
System.out.println(" longest: " + matcher.longestMatch(tests[i]));
}
}
/**
* {@inheritDoc}
*
* Returns true if the given String is matched by a suffix in the
* trie
*/
public boolean matches(String input) {
TrieNode node = root;
for (int i = input.length() - 1; i >= 0; i--) {
node = node.getChild(input.charAt(i));
if (node == null)
return false;
if (node.isTerminal())
return true;
}
return false;
}
/**
* {@inheritDoc}
*
* Returns the shortest suffix of input that is matched,
* or null if no match exists.
*/
public String shortestMatch(String input) {
TrieNode node = root;
for (int i = input.length() - 1; i >= 0; i--) {
node = node.getChild(input.charAt(i));
if (node == null)
return null;
if (node.isTerminal())
return input.substring(i);
}
return null;
}
/**
* {@inheritDoc}
*
* Returns the longest suffix of input that is matched,
* or null if no match exists.
*/
public String longestMatch(String input) {
TrieNode node = root;
String result = null;
for (int i = input.length() - 1; i >= 0; i--) {
node = node.getChild(input.charAt(i));
if (node == null)
break;
if (node.isTerminal())
result = input.substring(i);
}
return result;
}
}