org.springframework.boot.loader.ClassPathIndexFile Maven / Gradle / Ivy
/*
* Copyright 2012-2020 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.boot.loader;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URISyntaxException;
import java.net.URL;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;
/**
* A class path index file that provides ordering information for JARs.
*
* @author Madhura Bhave
* @author Phillip Webb
*/
final class ClassPathIndexFile {
private final File root;
private final List lines;
private ClassPathIndexFile(File root, List lines) {
this.root = root;
this.lines = lines.stream().map(this::extractName).collect(Collectors.toList());
}
private String extractName(String line) {
if (line.startsWith("- \"") && line.endsWith("\"")) {
return line.substring(3, line.length() - 1);
}
throw new IllegalStateException("Malformed classpath index line [" + line + "]");
}
int size() {
return this.lines.size();
}
boolean containsEntry(String name) {
if (name == null || name.isEmpty()) {
return false;
}
return this.lines.contains(name);
}
List getUrls() {
return Collections.unmodifiableList(this.lines.stream().map(this::asUrl).collect(Collectors.toList()));
}
private URL asUrl(String line) {
try {
return new File(this.root, line).toURI().toURL();
}
catch (MalformedURLException ex) {
throw new IllegalStateException(ex);
}
}
static ClassPathIndexFile loadIfPossible(URL root, String location) throws IOException {
return loadIfPossible(asFile(root), location);
}
private static ClassPathIndexFile loadIfPossible(File root, String location) throws IOException {
return loadIfPossible(root, new File(root, location));
}
private static ClassPathIndexFile loadIfPossible(File root, File indexFile) throws IOException {
if (indexFile.exists() && indexFile.isFile()) {
try (InputStream inputStream = new FileInputStream(indexFile)) {
return new ClassPathIndexFile(root, loadLines(inputStream));
}
}
return null;
}
private static List loadLines(InputStream inputStream) throws IOException {
List lines = new ArrayList<>();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, StandardCharsets.UTF_8));
String line = reader.readLine();
while (line != null) {
if (!line.trim().isEmpty()) {
lines.add(line);
}
line = reader.readLine();
}
return Collections.unmodifiableList(lines);
}
private static File asFile(URL url) {
if (!"file".equals(url.getProtocol())) {
throw new IllegalArgumentException("URL does not reference a file");
}
try {
return new File(url.toURI());
}
catch (URISyntaxException ex) {
return new File(url.getPath());
}
}
}