1 /*

     2  * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 package jdk.jfr.internal.jfc;

    27 import java.util.LinkedHashMap;

    28 import java.util.Map;

    29 

    30 import jdk.internal.org.xml.sax.Attributes;

    31 import jdk.internal.org.xml.sax.SAXException;

    32 import jdk.internal.org.xml.sax.helpers.DefaultHandler;

    33 

    34 final class JFCParserHandler extends DefaultHandler {

    35     private static final String ELEMENT_CONFIGURATION = "configuration";

    36     private static final String ELEMENT_EVENT_TYPE = "event";

    37     private static final String ELEMENT_SETTING = "setting";

    38     private static final String ATTRIBUTE_NAME = "name";

    39     private static final String ATTRIBUTE_LABEL = "label";

    40     private static final String ATTRIBUTE_DESCRIPTION = "description";

    41     private static final String ATTRIBUTE_PROVIDER = "provider";

    42     private static final String ATTRIBUTE_VERSION = "version";

    43 

    44     final Map<String, String> settings = new LinkedHashMap<String, String>();

    45     private String currentEventPath;

    46     private String currentSettingsName;

    47     private StringBuilder currentCharacters;

    48     String label;

    49     String provider;

    50     String description;

    51 

    52     @Override

    53     public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {

    54         switch (qName.toLowerCase()) {

    55         case ELEMENT_CONFIGURATION:

    56             String version = attributes.getValue(ATTRIBUTE_VERSION);

    57             if (version == null || !version.startsWith("2.")) {

    58                throw new SAXException("This version of Flight Recorder can only read JFC file format version 2.x");

    59             }

    60             label = attributes.getValue(ATTRIBUTE_LABEL);

    61             description = getOptional(attributes, ATTRIBUTE_DESCRIPTION, "");

    62             provider = getOptional(attributes, ATTRIBUTE_PROVIDER, "");

    63             break;

    64         case ELEMENT_EVENT_TYPE:

    65             currentEventPath = attributes.getValue(ATTRIBUTE_NAME);

    66             break;

    67         case ELEMENT_SETTING:

    68             currentSettingsName = attributes.getValue(ATTRIBUTE_NAME);

    69             break;

    70         }

    71         currentCharacters = null;

    72     }

    73 

    74     private String getOptional(Attributes attributes, String name, String defaultValue) {

    75         String value = attributes.getValue(name);

    76         return value == null ? defaultValue : value;

    77     }

    78 

    79     @Override

    80     public void characters(char[] ch, int start, int length) throws SAXException {

    81         if (currentCharacters == null) {

    82             currentCharacters = new StringBuilder(length);

    83         }

    84         currentCharacters.append(ch, start, length);

    85     }

    86 

    87     @Override

    88     public void endElement(String uri, String localName, String qName) {

    89         switch (qName.toLowerCase()) {

    90         case ELEMENT_CONFIGURATION:

    91             break;

    92         case ELEMENT_EVENT_TYPE:

    93             currentEventPath = null;

    94             break;

    95         case ELEMENT_SETTING:

    96             String settingsValue = currentCharacters == null ? "" : currentCharacters.toString();

    97             settings.put(currentEventPath + "#" + currentSettingsName, "" + settingsValue);

    98             currentSettingsName = null;

    99             break;

   100         }

   101     }

   102 

   103     public Map<String, String> getSettings() {

   104         return settings;

   105     }

   106 }