org.junit.platform.launcher.tagexpression.Tokenizer Maven / Gradle / Ivy
/*
* Copyright 2015-2019 the original author or authors.
*
* All rights reserved. This program and the accompanying materials are
* made available under the terms of the Eclipse Public License v2.0 which
* accompanies this distribution and is available at
*
* https://www.eclipse.org/legal/epl-v20.html
*/
package org.junit.platform.launcher.tagexpression;
import static java.util.Arrays.stream;
import static java.util.Collections.emptyList;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
/**
* @since 1.1
*/
class Tokenizer {
List tokenize(String infixTagExpression) {
if (infixTagExpression == null) {
return emptyList();
}
return deriveTokensFrom(infixTagExpression, trimmedTokenStringsFrom(infixTagExpression));
}
private List trimmedTokenStringsFrom(String infixTagExpression) {
String[] parts = infixTagExpression.replaceAll("([()!|&])", " $1 ").split("\\s");
return stream(parts).filter(part -> !part.isEmpty()).collect(Collectors.toList());
}
private List deriveTokensFrom(String infixTagExpression, List trimmedTokens) {
int startIndex = 0;
List tokens = new ArrayList<>(trimmedTokens.size());
for (String trimmedToken : trimmedTokens) {
Token token = extractTokenStartingAt(infixTagExpression, startIndex, trimmedToken);
startIndex = token.endIndexExclusive();
tokens.add(token);
}
return tokens;
}
private Token extractTokenStartingAt(String infixTagExpression, int startIndex, String trimmedToken) {
int foundAt = infixTagExpression.indexOf(trimmedToken, startIndex);
int endIndex = foundAt + trimmedToken.length();
String rawToken = infixTagExpression.substring(startIndex, endIndex);
return new Token(startIndex, rawToken);
}
}