JarUtil.java

/**
 * Copyright (c) 2015, Lucee Assosication Switzerland. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either 
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public 
 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 * 
 */
package lucee.runtime.osgi;

import java.io.IOException;
import java.io.InputStream;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;

import lucee.commons.io.IOUtil;
import lucee.commons.io.res.Resource;

import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.commons.Remapper;
import org.objectweb.asm.commons.RemappingClassAdapter;

public class JarUtil {
	
	public static final String[] DEFAULT_IGNORES=new String[]{
		"java.*"

	};
	
	
	/**
	 * 
	 * @param res
	 * @param ignores ".*" add the end includes all sub directories
	 * @return
	 * @throws IOException
	 */
	public static Set<String> getExternalImports(Resource res,String[] ignores) throws IOException {
		InputStream is = res.getInputStream();
		try {
			return getExternalImports(is,ignores);
		}
		finally{
			IOUtil.closeEL(is);
		}
	}

	
	public static Set<String> getExternalImports(InputStream is,String[] ignores) {
		Set<String> imports=new HashSet<>();
		Set<String> classNames=new HashSet<>();
		ZipInputStream zis = null;
		try{
			zis = new ZipInputStream(is);
			ZipEntry entry;
			String name;
			while((entry=zis.getNextEntry())!=null){
				if(entry.isDirectory() || !entry.getName().endsWith(".class")) continue;
				name=entry.getName();
				name=name.replace('/', '.');
				name=name.substring(0,name.length()-6);
				classNames.add(name);
				_getExternalImports(imports,zis,ignores);
			}
		}
		catch(IOException ioe) {
			ioe.printStackTrace();
		}
		finally {
			IOUtil.closeEL(zis);
		}
		
		// remove all class from this jar
		Iterator<String> it = classNames.iterator();
		String cn;
		while(it.hasNext()){
			cn=it.next();
			imports.remove(cn);
		}
		
		// create package set
		Set<String> importPackages=new HashSet<>();
		it = imports.iterator();
		int index;
		while(it.hasNext()){
			cn=it.next();
			index=cn.lastIndexOf('.');
			if(index==-1) continue; // no package
			importPackages.add(cn.substring(0,index));
		}
		return importPackages;
	}
	


	private static void _getExternalImports(Set<String> imports, InputStream src,String[] ignores) throws IOException{
		final ClassReader reader = new ClassReader(src);
		final Remapper remapper = new Collector(imports,ignores);
		final ClassVisitor inner = new EmptyVisitor();
		final RemappingClassAdapter visitor =
			new RemappingClassAdapter(inner, remapper);
		reader.accept(visitor, 0);
	}
	
	public static class Collector extends Remapper{

		private final Set<String> imports;
		private final String[] ignores;
		
		
		public Collector(final Set<String> imports,String[] ignores){
			this.imports = imports;
			this.ignores = ignores;
		}

		@Override
		public String mapDesc(final String desc){
			if(desc.startsWith("L")){
				this.addType(desc.substring(1, desc.length() - 1));
			}
			return super.mapDesc(desc);
		}

		@Override
		public String[] mapTypes(final String[] types){
			for(final String type : types){
				this.addType(type);
			}
			return super.mapTypes(types);
		}

		@Override
		public String mapType(final String type){
			this.addType(type);
			return type;
		}

		private void addType(final String type){
			String className = type.replace('/', '.');
			int index=className.lastIndexOf('.');
			if(index==-1) return;// class with no package
			String ignore,pack;
			
			for(int i=0;i<DEFAULT_IGNORES.length;i++){
				ignore=DEFAULT_IGNORES[i];
				// also ignore sub directories
				if(ignore.endsWith(".*")) {
					ignore=ignore.substring(0,ignore.length()-1);
					if(className.startsWith(ignore)) return;
				}
				else {
					pack=className.substring(0,index);
					if(pack.equals(ignore)) return;
				}
			}
			
			for(int i=0;i<ignores.length;i++){
				ignore=ignores[i];
				// also ignore sub directories
				if(ignore.endsWith(".*")) {
					ignore=ignore.substring(0,ignore.length()-1);
					if(className.startsWith(ignore)) return;
				}
				else {
					pack=className.substring(0,index);
					if(pack.equals(ignore)) return;
				}
				
				
			}
			this.imports.add(className);
		}
	}
	
	
	private static class EmptyVisitor extends ClassVisitor implements Opcodes {
		public EmptyVisitor() {
			super(ASM4);
		}
	}

}