ant/proposal/sandbox/embed/PropertyInterceptor.java

/*
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package org.apache.tools.ant;

import org.apache.tools.ant.helper.*;
import java.util.Enumeration;
import java.util.Locale;
import java.util.Vector;
import java.util.Hashtable;
import org.xml.sax.AttributeList;
import org.xml.sax.Attributes;
import org.xml.sax.helpers.AttributeListImpl;
import org.xml.sax.helpers.AttributesImpl;

/**
 * The new XML processor will use this interface to support
 * dynamic properties.
 *
 * Any task/type that implements this interface will be registered
 * and will receive notification of each property get operations
 * executed by the processor.
 *
 * XXX In ant1.6+, tasks implementing the interface will also
 * receive notification when a property is set. 
 *
 * @author Costin Manolache
 */
public interface PropertyInterceptor {

    /**
     * Called for each ${} property. If the result is null the
     * next PropertyInterceptor will be called. If all interceptors
     * return null, the properties stored in Project are used.
     */
    public Object getProperty( Project p, String ns, String name );

    /**
     *  Called when a property/reference is recorded.
     *  XXX Not implemented yet.
     */
    //    public boolean setProperty( String ns, String name, Object value );

}