RecordedClass.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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.
 *
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package jdk.jfr.consumer;

import java.lang.reflect.Modifier;
import java.util.List;

import jdk.jfr.ValueDescriptor;
import jdk.jfr.internal.Type;

/**
 * A recorded Java type, such as a class or an interface.
 *
 * @since 9
 */
public final class RecordedClass extends RecordedObject {

    static ObjectFactory<RecordedClass> createFactory(Type type, TimeConverter timeConverter) {
        return new ObjectFactory<RecordedClass>(type) {
            @Override
            RecordedClass createTyped(List<ValueDescriptor> desc, long id, Object[] object) {
                return new RecordedClass(desc, id, object, timeConverter);
            }
        };
    }

    private final long uniqueId;

    // package private
    private RecordedClass(List<ValueDescriptor> descriptors, long id, Object[] values, TimeConverter timeConverter) {
        super(descriptors, values, timeConverter);
        this.uniqueId = id;
    }

    /**
     * Returns the modifiers of the class.
     * <p>
     * See {@link java.lang.reflect.Modifier}
     *
     * @return the modifiers
     *
     * @see Modifier
     */
    public int getModifiers() {
        return getTyped("modifiers", Integer.class, -1);
    }

    /**
     * Returns the class loader that defined the class.
     * <P>
     * If the bootstrap class loader is represented as {@code null} in the Java
     * Virtual Machine (JVM), then {@code null} is also the return value of this method.
     *
     * @return the class loader defining this class, can be {@code null}
     */
    public RecordedClassLoader getClassLoader() {
        return getTyped("classLoader", RecordedClassLoader.class, null);
    }

    /**
     * Returns the fully qualified name of the class (for example,
     * {@code "java.lang.String"}).
     *
     * @return the class name, not {@code null}
     */
    public String getName() {
        return getTyped("name", String.class, null).replace("/", ".");
    }

    /**
     * Returns a unique ID for the class.
     * <p>
     * The ID might not be the same between Java Virtual Machine (JVM) instances.
     *
     * @return a unique ID
     */
    public long getId() {
        return uniqueId;
    }

    /**
     * Returns the object size for the class.
     * <p>
     * The object size for instance class is accurate. But for the array class, it
     * is a magic code 0x1111baba. The array object size can not be determined statically
     * from the JVM klass information because array object size is affected by
     * actual element length.
     *
     * @return the object size (instance object), or magic code 0x1111baba (array object)
     */
    public int getObjectSize() {
        return getTyped("objectSize", Integer.class, -1);
    }

    /**
     * Checks whether the class is for instance or array.
     *
     * @return true or false
     */
    public boolean isArray() {
        return getName().startsWith("[");
    }
}