org.springframework.aot.hint.support.FilePatternResourceHintsRegistrar Maven / Gradle / Ivy
/*
* Copyright 2002-2022 the original author or 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
*
* 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 org.springframework.aot.hint.support;
import java.util.ArrayList;
import java.util.List;
import org.springframework.aot.hint.ResourceHints;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.ResourceUtils;
/**
* Register the necessary resource hints for loading files from the classpath.
*
* Candidates are identified by a file name, a location, and an extension.
* The location can be the empty string to refer to the root of the classpath.
*
* @author Stephane Nicoll
* @since 6.0
*/
public class FilePatternResourceHintsRegistrar {
private final List names;
private final List locations;
private final List extensions;
/**
* Create a new instance for the specified file names, locations, and file
* extensions.
* @param names the file names
* @param locations the classpath locations
* @param extensions the file extensions (starts with a dot)
*/
public FilePatternResourceHintsRegistrar(List names, List locations,
List extensions) {
this.names = validateNames(names);
this.locations = validateLocations(locations);
this.extensions = validateExtensions(extensions);
}
private static List validateNames(List names) {
for (String name : names) {
if (name.contains("*")) {
throw new IllegalArgumentException("File name '" + name + "' cannot contain '*'");
}
}
return names;
}
private static List validateLocations(List locations) {
Assert.notEmpty(locations, "At least one location should be specified");
List parsedLocations = new ArrayList<>();
for (String location : locations) {
if (location.startsWith(ResourceUtils.CLASSPATH_URL_PREFIX)) {
location = location.substring(ResourceUtils.CLASSPATH_URL_PREFIX.length());
}
if (location.startsWith("/")) {
location = location.substring(1);
}
if (!location.isEmpty() && !location.endsWith("/")) {
location = location + "/";
}
parsedLocations.add(location);
}
return parsedLocations;
}
private static List validateExtensions(List extensions) {
for (String extension : extensions) {
if (!extension.startsWith(".")) {
throw new IllegalArgumentException("Extension '" + extension + "' should start with '.'");
}
}
return extensions;
}
public void registerHints(ResourceHints hints, @Nullable ClassLoader classLoader) {
ClassLoader classLoaderToUse = (classLoader != null) ? classLoader : getClass().getClassLoader();
List includes = new ArrayList<>();
for (String location : this.locations) {
if (classLoaderToUse.getResource(location) != null) {
for (String extension : this.extensions) {
for (String name : this.names) {
includes.add(location + name + "*" + extension);
}
}
}
}
if (!includes.isEmpty()) {
hints.registerPattern(hint -> hint.includes(includes.toArray(String[]::new)));
}
}
}