/*
 * 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
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 */
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.
/** * 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.
/** * 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<String> 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(); }