astproperty.java

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//--------------------------------------------------------------------------
//	Copyright (c) 1998-2004, Drew Davidson and Luke Blanshard
//  All rights reserved.
//
//	Redistribution and use in source and binary forms, with or without
//  modification, are permitted provided that the following conditions are
//  met:
//
//	Redistributions of source code must retain the above copyright notice,
//  this list of conditions and the following disclaimer.
//	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.
//	Neither the name of the Drew Davidson 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 ognl;

/**
 * @author Luke Blanshard ([e-mail])
 * @author Drew Davidson ([e-mail])
 */
class ASTProperty extends SimpleNode
{
    private boolean     indexedAccess = false;

    public ASTProperty(int id)
    {
        super(id);
    }

    public ASTProperty(OgnlParser p, int id)
    {
        super(p, id);
    }

    public void setIndexedAccess( boolean value )
    {
        indexedAccess = value;
    }

    /**
        Returns true iff this property is itself an index reference.
     */
    public boolean isIndexedAccess()
    {
        return indexedAccess;
    }

    /**
        Returns true if this property is described by an IndexedPropertyDescriptor
        and that if followed by an index specifier it will call the index get/set
        methods rather than go through property accessors.
     */
    public int getIndexedPropertyType(OgnlContext context, Object source) throws OgnlException
    {
        if (!isIndexedAccess()) {
            Object              property = getProperty(context, source);

            if (property instanceof String) {
                return OgnlRuntime.getIndexedPropertyType(context, (source == null) ? null : source.getClass(), (String)property);
            }
        }
        return OgnlRuntime.INDEXED_PROPERTY_NONE;
    }

    public Object getProperty( OgnlContext context, Object source ) throws OgnlException
    {
        return children[0].getValue( context, context.getRoot() );
    }

    protected Object getValueBody( OgnlContext context, Object source ) throws OgnlException
    {
        Object      result,
                    property = getProperty(context, source);
        Node        indexSibling;

        result = OgnlRuntime.getProperty( context, source, property );
        if (result == null) {
            result = OgnlRuntime.getNullHandler(OgnlRuntime.getTargetClass(source)).nullPropertyValue(context, source, property);
        }
        return result;
    }

    protected void setValueBody( OgnlContext context, Object target, Object value ) throws OgnlException
    {
        OgnlRuntime.setProperty( context, target, getProperty( context, target), value );
    }

    public boolean isNodeSimpleProperty( OgnlContext context ) throws OgnlException
    {
        return (children != null) && (children.length == 1) && ((SimpleNode)children[0]).isConstant(context);
    }

    public String toString()
    {
        String          result;

        if (isIndexedAccess()) {
            result = "[" + children[0] + "]";
        } else {
            result = ((ASTConst)children[0]).getValue().toString();
        }
        return result;
    }
}