Поиск SUBBYTES переписан на алгоритм Кнута-Моррриса-Пратта, добавлены тесты поиска паттернов

This commit is contained in:
serega6531
2020-04-16 02:08:30 +03:00
parent 07affe3812
commit 9eff4ecfe1
4 changed files with 161 additions and 10 deletions

View File

@@ -1,15 +1,18 @@
package ru.serega6531.packmate.service;
import lombok.SneakyThrows;
import org.apache.commons.lang3.StringUtils;
import org.springframework.security.crypto.codec.Hex;
import ru.serega6531.packmate.model.FoundPattern;
import ru.serega6531.packmate.model.Pattern;
import ru.serega6531.packmate.utils.BytesUtils;
import ru.serega6531.packmate.utils.KMPByteSearcher;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.util.*;
import java.util.regex.Matcher;
class PatternMatcher {
public class PatternMatcher {
private static final Map<String, java.util.regex.Pattern> compiledPatterns = new HashMap<>();
@@ -19,13 +22,13 @@ class PatternMatcher {
private final Set<FoundPattern> result = new HashSet<>();
PatternMatcher(byte[] contentBytes, List<Pattern> patterns) {
public PatternMatcher(byte[] contentBytes, List<Pattern> patterns) {
this.contentBytes = contentBytes;
this.content = new String(contentBytes);
this.patterns = patterns;
}
Set<FoundPattern> findMatches() {
public Set<FoundPattern> findMatches() {
patterns.forEach(this::match);
return result;
}
@@ -75,25 +78,25 @@ class PatternMatcher {
}
}
@SneakyThrows
private void matchSubbytes(Pattern pattern) {
int startSearch = 0;
final byte[] value = Hex.decode(pattern.getValue());
KMPByteSearcher searcher = new KMPByteSearcher(value);
InputStream is = new ByteArrayInputStream(contentBytes);
while (true) {
int start = BytesUtils.indexOf(contentBytes, value, startSearch, contentBytes.length);
int end = searcher.search(is) - 1;
if (start == -1) {
if (end < 0) {
return;
}
int end = start + value.length - 1;
int start = end - value.length + 1;
addIfPossible(FoundPattern.builder()
.patternId(pattern.getId())
.startPosition(start)
.endPosition(end)
.build());
startSearch = end + 1;
}
}