Field.java

/*******************************************************************************
 * Copyright (c) 1998, 2015 Oracle and/or its affiliates. All rights reserved.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation from Oracle TopLink
******************************************************************************/
package org.eclipse.persistence.tools.workbench.utility.classfile;

import java.io.IOException;
import java.io.PrintWriter;

import org.eclipse.persistence.tools.workbench.utility.classfile.descriptor.FieldType;
import org.eclipse.persistence.tools.workbench.utility.classfile.tools.ClassFileDataInputStream;


/**
 * This class models a class file field.
 *
 * See "The Java Virtual Machine Specification" Chapter 4.
 */
public class Field extends Member {
    private FieldType fieldDescriptor;        // lazy-initialized - so use the getter

    /** constants defined in "The Java Virtual Machine Specification" */
    public static final short ACC_ENUM = 0x4000;

    /**
     * cleared bits:
     *     0x8000 reserved for future use - ignore it
     *               (although the Eclipse compiler sets it for some reason...)
     *     0x4000 unrecognized by Modifier
     *     0x2000 unrecognized by Modifier
     *     0x1000 unrecognized by Modifier
     *     0x0800 strictfp
     *     0x0400 abstract
     *     0x0200 interface
     *     0x0100 native
     *     x00020 synchronized
     */
    public static final int VISIBLE_ACCESS_FLAGS_MASK = 0x00DF;


    /**
     * Construct a class file field from the specified stream
     * of byte codes.
     */
    Field(ClassFileDataInputStream stream, FieldPool pool) throws IOException {
        super(stream, pool);
    }

    short visibleAccessFlagsMask() {
        return VISIBLE_ACCESS_FLAGS_MASK;
    }

    public void printDeclarationOn(PrintWriter writer) {
        this.printModifierOn(writer);
        this.getFieldDescriptor().printDeclarationOn(writer);
        writer.print(' ');
        writer.print(this.name());
        this.getAttributePool().printFieldInitializationClauseOn(writer);
    }

    /**
     * Return the name that matches the name returned by
     * java.lang.reflect.Field.getType().getName().
     */
    public String javaTypeName() {
        return this.getFieldDescriptor().javaName();
    }

    public FieldPool getFieldPool() {
        return (FieldPool) this.getPool();
    }

    /**
     * Return the constant value assigned to a static field.
     */
    public Object constantValue() {
        return this.getAttributePool().fieldConstantValue();
    }

    /**
     * Check a bit that cannot (yet?) be interpreted by the
     * Modifier static methods. This bit indicates the field
     * is "being used to hold an element of an enumerated type".
     */
    public boolean isEnum() {
        return (this.getAccessFlags() & ACC_ENUM) != 0;
    }

    /**
     * as opposed to synthetic
     */
    public boolean isDeclaredField() {
        return ! this.isSynthetic();
    }

    public void accept(Visitor visitor) {
        visitor.visit(this);
        this.getFieldDescriptor().accept(visitor);
        super.accept(visitor);
    }

    public FieldType getFieldDescriptor() {
        if (this.fieldDescriptor == null) {
            this.fieldDescriptor = FieldType.createFieldType(this.descriptor());
        }
        return this.fieldDescriptor;
    }

}