Scala example source code file (AnnotationNode.java)

This example Scala source code file (AnnotationNode.java) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Scala source code examples by using tags.

All credit for the original source code belongs to scala-lang.org; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Scala tags/keywords

annotationnode, annotationvisitor, arraylist, asm, list, object, override, string

The AnnotationNode.java Scala example source code

/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2011 INRIA, France Telecom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
package scala.tools.asm.tree;

import java.util.ArrayList;
import java.util.List;

import scala.tools.asm.AnnotationVisitor;
import scala.tools.asm.Opcodes;

/**
 * A node that represents an annotationn.
 *
 * @author Eric Bruneton
 */
public class AnnotationNode extends AnnotationVisitor {

    /**
     * The class descriptor of the annotation class.
     */
    public String desc;

    /**
     * The name value pairs of this annotation. Each name value pair is stored
     * as two consecutive elements in the list. The name is a {@link String},
     * and the value may be a {@link Byte}, {@link Boolean}, {@link Character},
     * {@link Short}, {@link Integer}, {@link Long}, {@link Float},
     * {@link Double}, {@link String} or {@link scala.tools.asm.Type}, or an
     * two elements String array (for enumeration values), a
     * {@link AnnotationNode}, or a {@link List} of values of one of the
     * preceding types. The list may be <tt>null</tt> if there is no name value
     * pair.
     */
    public List<Object> values;

    /**
     * Constructs a new {@link AnnotationNode}. <i>Subclasses must not use this
     * constructor</i>. Instead, they must use the
     * {@link #AnnotationNode(int, String)} version.
     *
     * @param desc
     *            the class descriptor of the annotation class.
     */
    public AnnotationNode(final String desc) {
        this(Opcodes.ASM4, desc);
    }

    /**
     * Constructs a new {@link AnnotationNode}.
     *
     * @param api
     *            the ASM API version implemented by this visitor. Must be one
     *            of {@link Opcodes#ASM4}.
     * @param desc
     *            the class descriptor of the annotation class.
     */
    public AnnotationNode(final int api, final String desc) {
        super(api);
        this.desc = desc;
    }

    /**
     * Constructs a new {@link AnnotationNode} to visit an array value.
     *
     * @param values
     *            where the visited values must be stored.
     */
    AnnotationNode(final List<Object> values) {
        super(Opcodes.ASM4);
        this.values = values;
    }

    // ------------------------------------------------------------------------
    // Implementation of the AnnotationVisitor abstract class
    // ------------------------------------------------------------------------

    @Override
    public void visit(final String name, final Object value) {
        if (values == null) {
            values = new ArrayList<Object>(this.desc != null ? 2 : 1);
        }
        if (this.desc != null) {
            values.add(name);
        }
        values.add(value);
    }

    @Override
    public void visitEnum(final String name, final String desc,
            final String value) {
        if (values == null) {
            values = new ArrayList<Object>(this.desc != null ? 2 : 1);
        }
        if (this.desc != null) {
            values.add(name);
        }
        values.add(new String[] { desc, value });
    }

    @Override
    public AnnotationVisitor visitAnnotation(final String name,
            final String desc) {
        if (values == null) {
            values = new ArrayList<Object>(this.desc != null ? 2 : 1);
        }
        if (this.desc != null) {
            values.add(name);
        }
        AnnotationNode annotation = new AnnotationNode(desc);
        values.add(annotation);
        return annotation;
    }

    @Override
    public AnnotationVisitor visitArray(final String name) {
        if (values == null) {
            values = new ArrayList<Object>(this.desc != null ? 2 : 1);
        }
        if (this.desc != null) {
            values.add(name);
        }
        List<Object> array = new ArrayList<Object>();
        values.add(array);
        return new AnnotationNode(array);
    }

    @Override
    public void visitEnd() {
    }

    // ------------------------------------------------------------------------
    // Accept methods
    // ------------------------------------------------------------------------

    /**
     * Checks that this annotation node is compatible with the given ASM API
     * version. This methods checks that this node, and all its nodes
     * recursively, do not contain elements that were introduced in more recent
     * versions of the ASM API than the given version.
     *
     * @param api
     *            an ASM API version. Must be one of {@link Opcodes#ASM4}.
     */
    public void check(final int api) {
        // nothing to do
    }

    /**
     * Makes the given visitor visit this annotation.
     *
     * @param av
     *            an annotation visitor. Maybe <tt>null</tt>.
     */
    public void accept(final AnnotationVisitor av) {
        if (av != null) {
            if (values != null) {
                for (int i = 0; i < values.size(); i += 2) {
                    String name = (String) values.get(i);
                    Object value = values.get(i + 1);
                    accept(av, name, value);
                }
            }
            av.visitEnd();
        }
    }

    /**
     * Makes the given visitor visit a given annotation value.
     *
     * @param av
     *            an annotation visitor. Maybe <tt>null</tt>.
     * @param name
     *            the value name.
     * @param value
     *            the actual value.
     */
    static void accept(final AnnotationVisitor av, final String name,
            final Object value) {
        if (av != null) {
            if (value instanceof String[]) {
                String[] typeconst = (String[]) value;
                av.visitEnum(name, typeconst[0], typeconst[1]);
            } else if (value instanceof AnnotationNode) {
                AnnotationNode an = (AnnotationNode) value;
                an.accept(av.visitAnnotation(name, an.desc));
            } else if (value instanceof List) {
                AnnotationVisitor v = av.visitArray(name);
                List<?> array = (List<?>) value;
                for (int j = 0; j < array.size(); ++j) {
                    accept(v, null, array.get(j));
                }
                v.visitEnd();
            } else {
                av.visit(name, value);
            }
        }
    }
}