io.joshworks.snappy.maven.tools.JvmUtils Maven / Gradle / Ivy
/*
* Copyright 2012-2014 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
*
* http://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 io.joshworks.snappy.maven.tools;
import java.io.File;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
/**
* Java Virtual Machine Utils.
*
* @author Phillip Webb
*/
abstract class JvmUtils {
/**
* Various search locations for tools, including the odd Java 6 OSX jar.
*/
private static final String[] TOOLS_LOCATIONS = {"lib/tools.jar", "../lib/tools.jar",
"../Classes/classes.jar"};
public static ClassLoader getToolsClassLoader() {
ClassLoader systemClassLoader = ClassLoader.getSystemClassLoader();
return new URLClassLoader(new URL[]{getToolsJarUrl()}, systemClassLoader);
}
public static URL getToolsJarUrl() {
String javaHome = getJavaHome();
for (String location : TOOLS_LOCATIONS) {
try {
URL url = new URL(javaHome + "/" + location);
if (new File(url.toURI()).exists()) {
return url;
}
} catch (Exception ex) {
// Ignore and try the next location
}
}
throw new IllegalStateException("Unable to locate tools.jar");
}
private static String getJavaHome() {
try {
return new File(System.getProperty("java.home")).toURI().toURL()
.toExternalForm();
} catch (MalformedURLException e) {
throw new IllegalStateException("Cannot locate java.home", e);
}
}
}