| /* |
| * 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; |
| |
| import java.lang.annotation.Annotation; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Objects; |
| |
| import jdk.jfr.internal.AnnotationConstruct; |
| import jdk.jfr.internal.Type; |
| |
| /** |
| * Describes an event setting. |
| * |
| * @since 9 |
| */ |
| public final class SettingDescriptor { |
| |
| private final AnnotationConstruct annotationConstruct; |
| private final Type type; |
| private final String name; |
| private final String defaultValue; |
| |
| // package private, invoked by jdk.internal. |
| SettingDescriptor(Type type, String name, String defaultValue, List<AnnotationElement> annotations) { |
| Objects.requireNonNull(annotations); |
| this.name = Objects.requireNonNull(name, "Name of value descriptor can't be null"); |
| this.type = Objects.requireNonNull(type); |
| this.annotationConstruct = new AnnotationConstruct(annotations); |
| this.defaultValue = Objects.requireNonNull(defaultValue); |
| } |
| |
| // package private |
| void setAnnotations(List<AnnotationElement> as) { |
| annotationConstruct.setAnnotationElements(as); |
| } |
| |
| /** |
| * Returns the name of the setting (for example, {@code "threshold"}). |
| * |
| * @return the name, not {@code null} |
| */ |
| public String getName() { |
| return name; |
| } |
| |
| /** |
| * Returns a human-readable name that describes the setting (for example, |
| * {@code "Threshold"}). |
| * <p> |
| * If the setting lacks a label, the label for the type that is associated with this |
| * setting is returned, or {@code null} if doesn't exist |
| * |
| * @return a human-readable name, or {@code null} if doesn't exist |
| */ |
| public String getLabel() { |
| String label = annotationConstruct.getLabel(); |
| if (label == null) { |
| label = type.getLabel(); |
| } |
| return label; |
| } |
| |
| /** |
| * Returns a sentence that describes the setting (for example |
| * {@code "Record event with duration |
| * above or equal to threshold"}). |
| * <p> |
| * If the setting lacks a description, the description for the type that is |
| * associated with this setting is returned, or {@code null} if doesn't exist. |
| * |
| * @return the description, or {@code null} if doesn't exist |
| */ |
| public String getDescription() { |
| String description = annotationConstruct.getDescription(); |
| if (description == null) { |
| description = type.getDescription(); |
| } |
| return description; |
| } |
| |
| /** |
| * Returns a textual identifier that specifies how a value that is represented by |
| * this {@code SettingDescriptor} object is interpreted or formatted. |
| * <p> |
| * For example, if the setting descriptor represents a percentage, then |
| * {@code "jdk.jfr.Percentage"} hints to a client that a value of "0.5" |
| * is formatted as "50%". |
| * <p> |
| * The JDK provides the following predefined content types: |
| * <ul> |
| * <li>jdk.jfr.Percentage</li> |
| * <li>jdk.jfr.Timespan</li> |
| * <li>jdk.jfr.Timestamp</li> |
| * <li>jdk.jfr.Frequency</li> |
| * <li>jdk.jfr.Flag</li> |
| * <li>jdk.jfr.MemoryAddress</li> |
| * <li>jdk.jfr.DataAmount</li> |
| * <li>jdk.jfr.NetworkAddress</li> |
| * </ul> |
| * <p> |
| * User-defined content types can be created by using {@link ContentType}. |
| * <p> |
| * If the setting lacks a content type, the content type for the type |
| * that is associated with this setting is returned, or {@code null} if not |
| * available. |
| * |
| * @return the content type, or {@code null} if doesn't exist |
| * |
| * @see ContentType |
| */ |
| public String getContentType() { |
| for (AnnotationElement anno : getAnnotationElements()) { |
| for (AnnotationElement meta : anno.getAnnotationElements()) { |
| if (meta.getTypeName().equals(ContentType.class.getName())) { |
| return anno.getTypeName(); |
| } |
| } |
| } |
| for (AnnotationElement anno : type.getAnnotationElements()) { |
| for (AnnotationElement meta : anno.getAnnotationElements()) { |
| if (meta.getTypeName().equals(ContentType.class.getName())) { |
| return anno.getTypeName(); |
| } |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * Returns the fully qualified class name of the type that is associated with this |
| * setting descriptor. |
| * |
| * @return the type name, not {@code null} |
| * |
| * @see SettingDescriptor#getTypeId() |
| */ |
| public String getTypeName() { |
| return type.getName(); |
| } |
| |
| /** |
| * Returns a unique ID for the type in the Java Virtual Machine (JVM). |
| * <p> |
| * The ID might not be the same between JVM instances. |
| * |
| * @return the type ID, not negative |
| */ |
| public long getTypeId() { |
| return type.getId(); |
| } |
| |
| /** |
| * Returns the first annotation for the specified type if an annotation |
| * element with the same name is available, {@code null} otherwise. |
| * |
| * @param <A> the type of the annotation to query for and return if available |
| * @param annotationType the Class object that corresponds to the annotation |
| * type, not {@code null} |
| * @return this element's annotation for the specified annotation type if |
| * available, {@code null} otherwise |
| */ |
| public <A extends Annotation> A getAnnotation(Class<A> annotationType) { |
| Objects.requireNonNull(annotationType); |
| return annotationConstruct.getAnnotation(annotationType); |
| } |
| |
| /** |
| * Returns an immutable list of annotation elements for this value |
| * descriptor. |
| * |
| * @return a list of annotations, not {@code null} |
| */ |
| public List<AnnotationElement> getAnnotationElements() { |
| return Collections.unmodifiableList(annotationConstruct.getUnmodifiableAnnotationElements()); |
| } |
| |
| /** |
| * Returns the default value for this setting descriptor. |
| * |
| * @return the default value, not {@code null} |
| */ |
| public String getDefaultValue() { |
| return defaultValue; |
| } |
| |
| // package private |
| Type getType() { |
| return type; |
| } |
| } |