src/jdk.management.jfr/share/classes/jdk/management/jfr/SettingDescriptorInfo.java
changeset 50113 caf115bb98ad
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.management.jfr/share/classes/jdk/management/jfr/SettingDescriptorInfo.java	Tue May 15 20:24:34 2018 +0200
@@ -0,0 +1,232 @@
+/*
+ * 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.management.jfr;
+
+import java.util.concurrent.Callable;
+
+import javax.management.openmbean.CompositeData;
+
+import jdk.jfr.EventType;
+import jdk.jfr.SettingDescriptor;
+import jdk.management.jfr.internal.FlightRecorderMXBeanProvider;
+
+/**
+ * Management class that describes a setting, for example name, description and
+ * default value.
+ *
+ * @see EventType#getSettingDescriptors()
+ *
+ * @since 9
+ */
+public final class SettingDescriptorInfo {
+
+    // Purpose of this static initializer is to allow
+    // FlightRecorderMXBeanProvider
+    // to be in an internal package and not visible, but at the same time allow
+    // it to instantiate FlightRecorderMXBeanImpl.
+    //
+    // The reason the mechanism is in this class is because it is light weight
+    // and can easily be triggered from FlightRecorderMXBeanProvider.
+    static {
+        FlightRecorderMXBeanProvider.setFlightRecorderMXBeanFactory(new Callable<FlightRecorderMXBean>() {
+            @Override
+            public FlightRecorderMXBean call() throws Exception {
+                return new FlightRecorderMXBeanImpl();
+            }
+        });
+    }
+
+    private final String name;
+    private final String label;
+    private final String description;
+    private final String typeName;
+    private final String contentType;
+    private final String defaultValue;
+
+    // package private
+    SettingDescriptorInfo(SettingDescriptor settingDescriptor) {
+        this.name = settingDescriptor.getName();
+        this.label = settingDescriptor.getLabel();
+        this.description = settingDescriptor.getDescription();
+        this.typeName = settingDescriptor.getTypeName();
+        this.contentType = settingDescriptor.getContentType();
+        this.defaultValue = settingDescriptor.getDefaultValue();
+    }
+
+    private SettingDescriptorInfo(CompositeData cd) {
+        this.name = (String) cd.get("name");
+        this.label = (String) cd.get("label");
+        this.description = (String) cd.get("description");
+        this.typeName = (String) cd.get("typeName");
+        this.defaultValue = (String) cd.get("defaultValue");
+        this.contentType = (String) cd.get("contentType");
+    }
+
+    /**
+    * Returns the human-readable name of the setting associated with this
+     * {@code SettingDescriptorInfo} (for example, {@code "Threshold"}).
+     *
+     * @return the label for this setting, not {@code null}
+     */
+    public String getLabel() {
+        return label;
+    }
+
+    /**
+     * Returns the name of the setting associated with this
+     * {@code SettingDescriptorInfo} (for example, {@code "threshold"}).
+     *
+     * @return the name of this setting, not {@code null}
+     */
+    public String getName() {
+        return name;
+    }
+
+    /**
+     * Returns the description of the setting associated this
+     * {@code SettingDescriptorInfo} (for example,
+     * {@code "The duration an event must exceed to be be recorded"}).
+     *
+     * @return the description of this setting, not null
+     */
+    public String getDescription() {
+        return description;
+    }
+
+    /**
+     * Returns the type name of the setting associated this
+     * {@code SettingDescriptorInfo} (for example,
+     * {@code "jdk.settings.Threshold"}).
+     * <p>
+     * The type can be used to identify what type of setting this is.
+     *
+     * @return the name of this settings type, not {@code null}
+     */
+    public String getTypeName() {
+        return typeName;
+    }
+
+    /**
+     * Returns the content type of the setting associated this
+     * {@code SettingDescriptorInfo} (for example, {@code "jdk.jfr.Timespan"}).
+     * <p>
+     * The content type can be used to determine how the setting should be
+     * rendered in a graphical user interface.
+     *
+     * @return the name of this settings type, not {@code null}
+     */
+    public String getContentType() {
+        return contentType;
+    }
+
+    /**
+     * Returns the default value of the setting associated this
+     * {@code SettingDescriptorInfo} (for example, {@code "20 ms"}).
+     *
+     * @return default value for this setting, not {@code null}
+     *
+     * @see SettingDescriptor#getDefaultValue()
+     */
+    public String getDefaultValue() {
+        return defaultValue;
+    }
+
+    /**
+     * Returns an {@code SettingDescriptorInfo} represented by the specified
+     * {@code CompositeData}
+     * <p>
+     * The supplied {@code CompositeData} must have the following item names and
+     * item types to be valid. <blockquote>
+     * <table class="striped">
+     * <caption>The name and type the specified CompositeData must contain</caption>
+     * <thead>
+     * <tr>
+     * <th scope="col" style="text-align:left">Name</th>
+     * <th scope="col" style="text-align:left">Type</th>
+     * </tr>
+     * </thead>
+     * <tbody>
+     * <tr>
+     * <th scope="row">name</th>
+     * <td>{@code String}</td>
+     * </tr>
+     * <tr>
+     * <th scope="row">label</th>
+     * <td>{@code String}</td>
+     * </tr>
+     * <tr>
+     * <th scope="row">description</th>
+     * <td>{@code String}</td>
+     * </tr>
+     * <tr>
+     * <th scope="row">typeName</th>
+     * <td>{@code String}</td>
+     * </tr>
+     * <tr>
+     * <th scope="row">contentType</th>
+     * <td>{@code String}</td>
+     * </tr>
+     * <tr>
+     * <th scope="row">defaultValue</th>
+     * <td>{@code String}</td>
+     * </tr>
+     * </tbody>
+     * </table>
+     * </blockquote>
+     *
+     * @param cd {@code CompositeData} representing the {@code SettingDescriptorInfo} to
+     *        return
+     *
+     * @throws IllegalArgumentException if {@code cd} does not represent a valid
+     *         {@code EventTypeInfo}
+     *
+     * @return a {@code SettingDescriptorInfo}, or {@code null} if {@code cd} is
+     *         {@code null}
+     */
+    public static SettingDescriptorInfo from(CompositeData cd) {
+        if (cd == null) {
+            return null;
+        }
+        return new SettingDescriptorInfo(cd);
+    }
+
+    /**
+     * Returns a {@code String} description of this {@code SettingDescriptorInfo}.
+     *
+     * @return a string describing this setting, not {@code null}
+     */
+    @Override
+    public String toString() {
+        Stringifier s = new Stringifier();
+        s.add("name", name);
+        s.add("label", label);
+        s.add("description", description);
+        s.add("typeName", typeName);
+        s.add("contentType", contentType);
+        s.add("defaultValue", defaultValue);
+        return s.toString();
+    }
+}