diff -r 7a2a740815b7 -r caf115bb98ad src/jdk.jfr/share/classes/jdk/jfr/SettingDescriptor.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/jdk.jfr/share/classes/jdk/jfr/SettingDescriptor.java Tue May 15 20:24:34 2018 +0200 @@ -0,0 +1,215 @@ +/* + * 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 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 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"}). + *

+ * 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"}). + *

+ * 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. + *

+ * 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%". + *

+ * The JDK provides the following predefined content types: + *

+ *

+ * User-defined content types can be created by using {@link ContentType}. + *

+ * 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). + *

+ * 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 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 getAnnotation(Class 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 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; + } +}