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/*
* Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package jdk.internal.vm;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Properties;
import java.util.Set;
import java.util.jar.JarFile;
import java.util.jar.Manifest;
import java.util.jar.Attributes;
/*
* Support class used by JVMTI and VM attach mechanism.
*/
public class VMSupport {
private static Properties agentProps = null;
/**
* Returns the agent properties.
*/
public static synchronized Properties getAgentProperties() {
if (agentProps == null) {
agentProps = new Properties();
initAgentProperties(agentProps);
}
return agentProps;
}
private static native Properties initAgentProperties(Properties props);
/**
* Write the given properties list to a byte array and return it. Properties with
* a key or value that is not a String is filtered out. The stream written to the byte
* array is ISO 8859-1 encoded.
*/
private static byte[] serializePropertiesToByteArray(Properties p) throws IOException {
ByteArrayOutputStream out = new ByteArrayOutputStream(4096);
Properties props = new Properties();
// stringPropertyNames() returns a snapshot of the property keys
Set keyset = p.stringPropertyNames();
for (String key : keyset) {
String value = p.getProperty(key);
props.put(key, value);
}
props.store(out, null);
return out.toByteArray();
}
public static byte[] serializePropertiesToByteArray() throws IOException {
return serializePropertiesToByteArray(System.getProperties());
}
public static byte[] serializeAgentPropertiesToByteArray() throws IOException {
return serializePropertiesToByteArray(getAgentProperties());
}
/*
* Returns true if the given JAR file has the Class-Path attribute in the
* main section of the JAR manifest. Throws RuntimeException if the given
* path is not a JAR file or some other error occurs.
*/
public static boolean isClassPathAttributePresent(String path) {
try {
Manifest man = (new JarFile(path)).getManifest();
if (man != null) {
if (man.getMainAttributes().getValue(Attributes.Name.CLASS_PATH) != null) {
return true;
}
}
return false;
} catch (IOException ioe) {
throw new RuntimeException(ioe.getMessage());
}
}
/*
* Return the temporary directory that the VM uses for the attach
* and perf data files.
*
* It is important that this directory is well-known and the
* same for all VM instances. It cannot be affected by configuration
* variables such as java.io.tmpdir.
*/
public static native String getVMTemporaryDirectory();
}