org.springframework.boot.system.ApplicationHome 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.system;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.JarURLConnection;
import java.net.URISyntaxException;
import java.net.URL;
import java.net.URLConnection;
import java.security.CodeSource;
import java.security.ProtectionDomain;
import java.util.Enumeration;
import java.util.jar.JarFile;
import java.util.jar.Manifest;
import org.springframework.util.ClassUtils;
import org.springframework.util.StringUtils;
/**
* Provides access to the application home directory. Attempts to pick a sensible home for
* both Jar Files, Exploded Archives and directly running applications.
*
* @author Phillip Webb
* @author Raja Kolli
* @since 2.0.0
*/
public class ApplicationHome {
private final File source;
private final File dir;
/**
* Create a new {@link ApplicationHome} instance.
*/
public ApplicationHome() {
this(null);
}
/**
* Create a new {@link ApplicationHome} instance for the specified source class.
* @param sourceClass the source class or {@code null}
*/
public ApplicationHome(Class sourceClass) {
this.source = findSource((sourceClass != null) ? sourceClass : getStartClass());
this.dir = findHomeDir(this.source);
}
private Class getStartClass() {
try {
ClassLoader classLoader = getClass().getClassLoader();
return getStartClass(classLoader.getResources("META-INF/MANIFEST.MF"));
}
catch (Exception ex) {
return null;
}
}
private Class getStartClass(Enumeration manifestResources) {
while (manifestResources.hasMoreElements()) {
try (InputStream inputStream = manifestResources.nextElement().openStream()) {
Manifest manifest = new Manifest(inputStream);
String startClass = manifest.getMainAttributes().getValue("Start-Class");
if (startClass != null) {
return ClassUtils.forName(startClass, getClass().getClassLoader());
}
}
catch (Exception ex) {
}
}
return null;
}
private File findSource(Class sourceClass) {
try {
ProtectionDomain domain = (sourceClass != null) ? sourceClass.getProtectionDomain() : null;
CodeSource codeSource = (domain != null) ? domain.getCodeSource() : null;
URL location = (codeSource != null) ? codeSource.getLocation() : null;
File source = (location != null) ? findSource(location) : null;
if (source != null && source.exists() && !isUnitTest()) {
return source.getAbsoluteFile();
}
return null;
}
catch (Exception ex) {
return null;
}
}
private boolean isUnitTest() {
try {
StackTraceElement[] stackTrace = Thread.currentThread().getStackTrace();
for (int i = stackTrace.length - 1; i >= 0; i--) {
if (stackTrace[i].getClassName().startsWith("org.junit.")) {
return true;
}
}
}
catch (Exception ex) {
}
return false;
}
private File findSource(URL location) throws IOException, URISyntaxException {
URLConnection connection = location.openConnection();
if (connection instanceof JarURLConnection) {
return getRootJarFile(((JarURLConnection) connection).getJarFile());
}
return new File(location.toURI());
}
private File getRootJarFile(JarFile jarFile) {
String name = jarFile.getName();
int separator = name.indexOf("!/");
if (separator > 0) {
name = name.substring(0, separator);
}
return new File(name);
}
private File findHomeDir(File source) {
File homeDir = source;
homeDir = (homeDir != null) ? homeDir : findDefaultHomeDir();
if (homeDir.isFile()) {
homeDir = homeDir.getParentFile();
}
homeDir = homeDir.exists() ? homeDir : new File(".");
return homeDir.getAbsoluteFile();
}
private File findDefaultHomeDir() {
String userDir = System.getProperty("user.dir");
return new File(StringUtils.hasLength(userDir) ? userDir : ".");
}
/**
* Returns the underlying source used to find the home directory. This is usually the
* jar file or a directory. Can return {@code null} if the source cannot be
* determined.
* @return the underlying source or {@code null}
*/
public File getSource() {
return this.source;
}
/**
* Returns the application home directory.
* @return the home directory (never {@code null})
*/
public File getDir() {
return this.dir;
}
@Override
public String toString() {
return getDir().toString();
}
}