com.google.apphosting.utils.glob.AbstractGlob Maven / Gradle / Ivy
/*
* Copyright 2021 Google LLC
*
* 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
*
* https://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.apphosting.utils.glob;
import java.util.regex.Pattern;
/**
* Abstract parent for {@link LeafGlob} and {@link BranchGlob}.
*
*/
abstract class AbstractGlob implements Glob {
/**
* This is just an arbitrary string that is unlikely to overlap with
* the user's URLs. We replace any wildcards in a target regular
* expression to see if another regular expression matches every
* possible pattern. Think of this as the most unlikely string that
* could match a wildcard.
*/
private static final String SENTINEL_VALUE = "_-= (S3Nt!N\\$L) =-_";
protected final String pattern;
public AbstractGlob(String pattern) {
this.pattern = pattern;
}
@Override
public String getPattern() {
return pattern;
}
@Override
public boolean isLiteral() {
return pattern.indexOf("*") == -1;
}
@Override
public Pattern getRegularExpression() {
String regex = pattern;
// First we escape non-literals with a backslash (note that
// Pattern.quote is sneaky and not useful for this).
regex = regex.replaceAll("([^A-Za-z0-9\\-_/])", "\\\\$1");
// Now we replace any literal star character with .* so it matches
// zero or more characters.
regex = regex.replaceAll("\\\\\\*", ".*");
return Pattern.compile(regex);
}
@Override
public boolean matches(String string) {
return getRegularExpression().matcher(string).matches();
}
@Override
public boolean matchesAll(Glob glob) {
return matchesAll(glob.getPattern());
}
@Override
public boolean matchesAll(String pattern) {
return matches(pattern.replaceAll("\\*", SENTINEL_VALUE));
}
@Override
public boolean equals(Object object) {
if (object instanceof AbstractGlob) {
AbstractGlob glob = (AbstractGlob) object;
return pattern.equals(glob.pattern);
}
return false;
}
@Override
public int hashCode() {
return pattern.hashCode();
}
@Override
public String toString() {
return pattern;
}
}