Java example source code file (FieldWriter.java)

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Java - Java tags/keywords

annotationvisitor, annotationwriter, attribute, bytevector, classwriter, constantvalue, deprecated, fieldwriter, object, runtimeinvisibleannotations, runtimevisibleannotations, signature, string, synthetic

The FieldWriter.java Java example source code

/*
 * Copyright (c) 2005, 2009, 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.
 */

/*
 * This file is available under and governed by the GNU General Public
 * License version 2 only, as published by the Free Software Foundation.
 * However, the following notice accompanied the original version of this
 * file:
 *
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2007 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 com.sun.xml.internal.ws.org.objectweb.asm;

/**
 * An {@link FieldVisitor} that generates Java fields in bytecode form.
 *
 * @author Eric Bruneton
 */
final class FieldWriter implements FieldVisitor {

    /**
     * Next field writer (see {@link ClassWriter#firstField firstField}).
     */
    FieldWriter next;

    /**
     * The class writer to which this field must be added.
     */
    private final ClassWriter cw;

    /**
     * Access flags of this field.
     */
    private final int access;

    /**
     * The index of the constant pool item that contains the name of this
     * method.
     */
    private final int name;

    /**
     * The index of the constant pool item that contains the descriptor of this
     * field.
     */
    private final int desc;

    /**
     * The index of the constant pool item that contains the signature of this
     * field.
     */
    private int signature;

    /**
     * The index of the constant pool item that contains the constant value of
     * this field.
     */
    private int value;

    /**
     * The runtime visible annotations of this field. May be <tt>null.
     */
    private AnnotationWriter anns;

    /**
     * The runtime invisible annotations of this field. May be <tt>null.
     */
    private AnnotationWriter ianns;

    /**
     * The non standard attributes of this field. May be <tt>null.
     */
    private Attribute attrs;

    // ------------------------------------------------------------------------
    // Constructor
    // ------------------------------------------------------------------------

    /**
     * Constructs a new {@link FieldWriter}.
     *
     * @param cw the class writer to which this field must be added.
     * @param access the field's access flags (see {@link Opcodes}).
     * @param name the field's name.
     * @param desc the field's descriptor (see {@link Type}).
     * @param signature the field's signature. May be <tt>null.
     * @param value the field's constant value. May be <tt>null.
     */
    FieldWriter(
        final ClassWriter cw,
        final int access,
        final String name,
        final String desc,
        final String signature,
        final Object value)
    {
        if (cw.firstField == null) {
            cw.firstField = this;
        } else {
            cw.lastField.next = this;
        }
        cw.lastField = this;
        this.cw = cw;
        this.access = access;
        this.name = cw.newUTF8(name);
        this.desc = cw.newUTF8(desc);
        if (ClassReader.SIGNATURES && signature != null) {
            this.signature = cw.newUTF8(signature);
        }
        if (value != null) {
            this.value = cw.newConstItem(value).index;
        }
    }

    // ------------------------------------------------------------------------
    // Implementation of the FieldVisitor interface
    // ------------------------------------------------------------------------

    public AnnotationVisitor visitAnnotation(
        final String desc,
        final boolean visible)
    {
        if (!ClassReader.ANNOTATIONS) {
            return null;
        }
        ByteVector bv = new ByteVector();
        // write type, and reserve space for values count
        bv.putShort(cw.newUTF8(desc)).putShort(0);
        AnnotationWriter aw = new AnnotationWriter(cw, true, bv, bv, 2);
        if (visible) {
            aw.next = anns;
            anns = aw;
        } else {
            aw.next = ianns;
            ianns = aw;
        }
        return aw;
    }

    public void visitAttribute(final Attribute attr) {
        attr.next = attrs;
        attrs = attr;
    }

    public void visitEnd() {
    }

    // ------------------------------------------------------------------------
    // Utility methods
    // ------------------------------------------------------------------------

    /**
     * Returns the size of this field.
     *
     * @return the size of this field.
     */
    int getSize() {
        int size = 8;
        if (value != 0) {
            cw.newUTF8("ConstantValue");
            size += 8;
        }
        if ((access & Opcodes.ACC_SYNTHETIC) != 0
                && (cw.version & 0xffff) < Opcodes.V1_5)
        {
            cw.newUTF8("Synthetic");
            size += 6;
        }
        if ((access & Opcodes.ACC_DEPRECATED) != 0) {
            cw.newUTF8("Deprecated");
            size += 6;
        }
        if (ClassReader.SIGNATURES && signature != 0) {
            cw.newUTF8("Signature");
            size += 8;
        }
        if (ClassReader.ANNOTATIONS && anns != null) {
            cw.newUTF8("RuntimeVisibleAnnotations");
            size += 8 + anns.getSize();
        }
        if (ClassReader.ANNOTATIONS && ianns != null) {
            cw.newUTF8("RuntimeInvisibleAnnotations");
            size += 8 + ianns.getSize();
        }
        if (attrs != null) {
            size += attrs.getSize(cw, null, 0, -1, -1);
        }
        return size;
    }

    /**
     * Puts the content of this field into the given byte vector.
     *
     * @param out where the content of this field must be put.
     */
    void put(final ByteVector out) {
        out.putShort(access).putShort(name).putShort(desc);
        int attributeCount = 0;
        if (value != 0) {
            ++attributeCount;
        }
        if ((access & Opcodes.ACC_SYNTHETIC) != 0
                && (cw.version & 0xffff) < Opcodes.V1_5)
        {
            ++attributeCount;
        }
        if ((access & Opcodes.ACC_DEPRECATED) != 0) {
            ++attributeCount;
        }
        if (ClassReader.SIGNATURES && signature != 0) {
            ++attributeCount;
        }
        if (ClassReader.ANNOTATIONS && anns != null) {
            ++attributeCount;
        }
        if (ClassReader.ANNOTATIONS && ianns != null) {
            ++attributeCount;
        }
        if (attrs != null) {
            attributeCount += attrs.getCount();
        }
        out.putShort(attributeCount);
        if (value != 0) {
            out.putShort(cw.newUTF8("ConstantValue"));
            out.putInt(2).putShort(value);
        }
        if ((access & Opcodes.ACC_SYNTHETIC) != 0
                && (cw.version & 0xffff) < Opcodes.V1_5)
        {
            out.putShort(cw.newUTF8("Synthetic")).putInt(0);
        }
        if ((access & Opcodes.ACC_DEPRECATED) != 0) {
            out.putShort(cw.newUTF8("Deprecated")).putInt(0);
        }
        if (ClassReader.SIGNATURES && signature != 0) {
            out.putShort(cw.newUTF8("Signature"));
            out.putInt(2).putShort(signature);
        }
        if (ClassReader.ANNOTATIONS && anns != null) {
            out.putShort(cw.newUTF8("RuntimeVisibleAnnotations"));
            anns.put(out);
        }
        if (ClassReader.ANNOTATIONS && ianns != null) {
            out.putShort(cw.newUTF8("RuntimeInvisibleAnnotations"));
            ianns.put(out);
        }
        if (attrs != null) {
            attrs.put(cw, null, 0, -1, -1, out);
        }
    }
}