/*
* Copyright (c) 2016, 2018, 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.jfr.internal.jfc;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.NoSuchFileException;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.text.ParseException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import jdk.jfr.Configuration;
import jdk.jfr.internal.LogLevel;
import jdk.jfr.internal.LogTag;
import jdk.jfr.internal.Logger;
import jdk.jfr.internal.SecuritySupport;
import jdk.jfr.internal.SecuritySupport.SafePath;
/**
* {@link Configuration} factory for JFC files. *
*/
public final class JFC {
private static final int BUFFER_SIZE = 8192;
private static final int MAXIMUM_FILE_SIZE = 1024 * 1024;
private static final int MAX_BUFFER_SIZE = Integer.MAX_VALUE - 8;
private static volatile List<KnownConfiguration> knownConfigurations;
/**
* Reads a known configuration file (located into a string, but doesn't
* parse it until it's being used.
*/
private static final class KnownConfiguration {
private final String content;
private final String filename;
private final String name;
private Configuration configuration;
public KnownConfiguration(SafePath knownPath) throws IOException {
this.content = readContent(knownPath);
this.name = nameFromPath(knownPath.toPath());
this.filename = nullSafeFileName(knownPath.toPath());
}
public boolean isNamed(String name) {
return filename.equals(name) || this.name.equals(name);
}
public Configuration getConfigurationFile() throws IOException, ParseException {
if (configuration == null) {
configuration = JFCParser.createConfiguration(name, content);
}
return configuration;
}
public String getName() {
return name;
}
private static String readContent(SafePath knownPath) throws IOException {
if (SecuritySupport.getFileSize(knownPath) > MAXIMUM_FILE_SIZE) {
throw new IOException("Configuration with more than "
+ MAXIMUM_FILE_SIZE + " characters can't be read.");
}
try (InputStream r = SecuritySupport.newFileInputStream(knownPath)) {
return JFC.readContent(r);
}
}
}
private JFC() {
// private utility class
}
/**
* Reads a configuration from a file.
*
* @param path the file containing the configuration, not {@code null}
* @return {@link Configuration}, not {@code null}
* @throws ParseException if the file can't be parsed
* @throws IOException if the file can't be read
*
* @throws SecurityException if a security manager exists and its
* <code>checkRead</code> method denies read access to the file.
* @see java.io.File#getPath()
* @see java.lang.SecurityManager#checkRead(java.lang.String)
*/
public static Configuration create(String name, Reader reader) throws IOException, ParseException {
return JFCParser.createConfiguration(name, reader);
}
private static String nullSafeFileName(Path file) throws IOException {
Path filename = file.getFileName();
if (filename == null) {
throw new IOException("Path has no file name");
}
return filename.toString();
}
public static String nameFromPath(Path file) throws IOException {
String f = nullSafeFileName(file);
if (f.endsWith(JFCParser.FILE_EXTENSION)) {
return f.substring(0, f.length() - JFCParser.FILE_EXTENSION.length());
} else {
return f;
}
}
// Invoked by DCmdStart
public static Configuration createKnown(String name) throws IOException, ParseException {
// Known name, no need for permission
for (KnownConfiguration known : getKnownConfigurations()) {
if (known.isNamed(name)) {
return known.getConfigurationFile();
}
}
// Check JFC directory
SafePath path = SecuritySupport.JFC_DIRECTORY;
if (path != null && SecuritySupport.exists(path)) {
for (String extension : Arrays.asList("", JFCParser.FILE_EXTENSION)) {
SafePath file = new SafePath(path.toPath().resolveSibling(name + extension));
if (SecuritySupport.exists(file) && !SecuritySupport.isDirectory(file)) {
try (Reader r = SecuritySupport.newFileReader(file)) {
String jfcName = nameFromPath(file.toPath());
return JFCParser.createConfiguration(jfcName, r);
}
}
}
}
// Assume path included in name
Path localPath = Paths.get(name);
String jfcName = nameFromPath(localPath);
try (Reader r = Files.newBufferedReader(localPath)) {
return JFCParser.createConfiguration(jfcName, r);
}
}
private static String readContent(InputStream source) throws IOException {
byte[] bytes = read(source, BUFFER_SIZE);
return new String(bytes, StandardCharsets.UTF_8);
}
// copied from java.io.file.Files to avoid dependency on JDK 9 code
private static byte[] read(InputStream source, int initialSize) throws IOException {
int capacity = initialSize;
byte[] buf = new byte[capacity];
int nread = 0;
int n;
for (;;) {
// read to EOF which may read more or less than initialSize (eg: file
// is truncated while we are reading)
while ((n = source.read(buf, nread, capacity - nread)) > 0)
nread += n;
// if last call to source.read() returned -1, we are done
// otherwise, try to read one more byte; if that failed we're done too
if (n < 0 || (n = source.read()) < 0)
break;
// one more byte was read; need to allocate a larger buffer
if (capacity <= MAX_BUFFER_SIZE - capacity) {
capacity = Math.max(capacity << 1, BUFFER_SIZE);
} else {
if (capacity == MAX_BUFFER_SIZE)
throw new OutOfMemoryError("Required array size too large");
capacity = MAX_BUFFER_SIZE;
}
buf = Arrays.copyOf(buf, capacity);
buf[nread++] = (byte)n;
}
return (capacity == nread) ? buf : Arrays.copyOf(buf, nread);
}
/**
* Returns list of predefined configurations available.
*
* @return list of configurations, not null
*/
public static List<Configuration> getConfigurations() {
List<Configuration> configs = new ArrayList<>();
for (KnownConfiguration knownConfig : getKnownConfigurations()) {
try {
configs.add(knownConfig.getConfigurationFile());
} catch (IOException e) {
Logger.log(LogTag.JFR, LogLevel.WARN, "Could not load configuration " + knownConfig.getName() + ". " + e.getMessage());
} catch (ParseException e) {
Logger.log(LogTag.JFR, LogLevel.WARN, "Could not parse configuration " + knownConfig.getName() + ". " + e.getMessage());
}
}
return configs;
/**代码未完, 请加载全部代码(NowJava.com).**/