/*
 * Copyright (c) 2005, 2006, 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
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package com.sun.tools.internal.xjc.outline;

import com.sun.codemodel.internal.JBlock;
import com.sun.codemodel.internal.JExpression;
import com.sun.codemodel.internal.JVar;
import com.sun.tools.internal.xjc.model.CPropertyInfo;

/**
 * Encapsulates the access on a field.
 * 
 * @author
 *     Kohsuke Kawaguchi (kohsuke.kawaguchi@sun.com)
 */
public interface FieldAccessor {

    /**
     * Dumps everything in this field into the given variable.
     * 
     * <p>
     * This generates code that accesses the field from outside.
     * 
     * @param block
     *      The code will be generated into this block.
     * @param $var
     *      Variable whose type is {@link FieldOutline#getRawType()}
     */
    void toRawValue( JBlock block, JVar $var );
    
    /**
     * Sets the value of the field from the specified expression.
     * 
     * <p>
     * This generates code that accesses the field from outside.
     * 
     * @param block
     *      The code will be generated into this block.
     * @param uniqueName
     *      Identifier that the caller guarantees to be unique in
     *      the given block. When the callee needs to produce additional
     *      variables, it can do so by adding suffixes to this unique
     *      name. For example, if the uniqueName is "abc", then the 
     *      caller guarantees that any identifier "abc.*" is unused
     *      in this block.
     * @param $var
     *      The expression that evaluates to a value of the type
     *      {@link FieldOutline#getRawType()}.
     */
    void fromRawValue( JBlock block, String uniqueName, JExpression $var );
    
    /**
     * Generates a code fragment to remove any "set" value
     * and move this field to the "unset" state.
     * 
     * @param body
     *      The code will be appended at the end of this block.
     */
    void unsetValues( JBlock body );
    
    /**
     * Return an expression that evaluates to true only when
     * this field has a set value(s).
     * 
     * @return null
     *      if the isSetXXX/unsetXXX method does not make sense 
     *      for the given field.
     */
    JExpression hasSetValue();

    /**
     * Gets the {@link FieldOutline} from which
     * this object is created.
     */
    FieldOutline owner();

    /**
     * Short for <tt>owner().getPropertyInfo()</tt>
     */
    CPropertyInfo getPropertyInfo();
}
