org.aspectj/weaver/src/org/aspectj/weaver/bcel/BcelAttributes.java

/* *******************************************************************
 * Copyright (c) 2002 Palo Alto Research Center, Incorporated (PARC).
 * All rights reserved. 
 * This program and the accompanying materials are made available 
 * under the terms of the Eclipse Public License v1.0 
 * which accompanies this distribution and is available at 
 * http://www.eclipse.org/legal/epl-v10.html 
 *  
 * Contributors: 
 *     PARC     initial implementation 
 * ******************************************************************/


package org.aspectj.weaver.bcel;

import java.util.ArrayList;
import java.util.List;

import org.aspectj.apache.bcel.classfile.Attribute;
import org.aspectj.apache.bcel.classfile.Unknown;
import org.aspectj.weaver.AjAttribute;
import org.aspectj.weaver.BCException;
import org.aspectj.weaver.ISourceContext;
import org.aspectj.weaver.World;
import org.aspectj.weaver.AjAttribute.WeaverVersionInfo;


// this is a class o' static methods for reading attributes.  It's pretty much a bridge from 
// bcel to AjAttribute.
// OPTIMIZE move the contents of this class to bcel Utility
class BcelAttributes {

	/**
	 * Process an array of Bcel attributes - looking for those with the name prefix org.aspectj.weaver.  The returned 
	 * list contains the AspectJ attributes identified and unpacked to 'AjAttribute' objects.
	 */
//	public static List readAjAttributes(String classname,List as, ISourceContext context,
//			                              World w, AjAttribute.WeaverVersionInfo version) {
//		List l = new ArrayList();
//		
//		// first pass, look for version
//		List forSecondPass = new ArrayList();
//		for (int i = as.size() - 1; i >= 0; i--) {
//			Attribute a = (Attribute)as.get(i);
//			if (a instanceof Unknown) {
//				Unknown u = (Unknown) a;
//				String name = u.getName();
//				if (name.charAt(0)=='o') { // 'o'rg.aspectj
//					if (name.startsWith(AjAttribute.AttributePrefix)) {
//						if (name.endsWith(WeaverVersionInfo.AttributeName)) {
//							version = (AjAttribute.WeaverVersionInfo)AjAttribute.read(version,name,u.getBytes(),context,w);
//							if (version.getMajorVersion() > WeaverVersionInfo.getCurrentWeaverMajorVersion()) {
//								throw new BCException("Unable to continue, this version of AspectJ supports classes built with weaver version "+
//										WeaverVersionInfo.toCurrentVersionString()+" but the class "+classname+" is version "+version.toString());
//							}
//	                    }
//						forSecondPass.add(a);
//					}
//				}
//			}
//		}
				
//		for (int i = forSecondPass.size()-1; i >= 0; i--) {
//			Unknown a = (Unknown)forSecondPass.get(i);
//			String name = a.getName();
//			AjAttribute attr = AjAttribute.read(version,name,a.getBytes(),context,w); 
//			if (attr!=null) l.add(attr);
//		}
//		return l;
//	}
	public static List readAjAttributes(String classname, Attribute[] as, ISourceContext context, World w, AjAttribute.WeaverVersionInfo version) {
		List l = new ArrayList();

		// first pass, look for version
		List forSecondPass = new ArrayList();
		for (int i = as.length - 1; i >= 0; i--) {
			Attribute a = as[i];
			if (a instanceof Unknown) {
				Unknown u = (Unknown) a;
				String name = u.getName();
				if (name.charAt(0) == 'o') { // 'o'rg.aspectj
					if (name.startsWith(AjAttribute.AttributePrefix)) {
						if (name.endsWith(WeaverVersionInfo.AttributeName)) {
							version = (AjAttribute.WeaverVersionInfo) AjAttribute.read(version, name, u.getBytes(), context, w);
							if (version.getMajorVersion() > WeaverVersionInfo
									.getCurrentWeaverMajorVersion()) {
								throw new BCException(
										"Unable to continue, this version of AspectJ supports classes built with weaver version "
												+ WeaverVersionInfo
														.toCurrentVersionString()
												+ " but the class "
												+ classname
												+ " is version "
												+ version.toString());
							}
						}
						forSecondPass.add(a);
					}
				}
			}
		}

		for (int i = forSecondPass.size() - 1; i >= 0; i--) {
			Unknown a = (Unknown) forSecondPass.get(i);
			String name = a.getName();
			AjAttribute attr = AjAttribute.read(version, name, a.getBytes(), context, w);
			if (attr != null) l.add(attr);
		}
		return l;
	}
}