printclass.java

A static analysis tool to find bugs in Java programs

/*
 * FindBugs - Find Bugs in Java programs
 * Copyright (C) 2006, University of Maryland
 * 
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package edu.umd.cs.findbugs.visitclass;

import java.io.IOException;
import java.io.Serializable;
import java.util.Comparator;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.TreeSet;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

import org.apache.bcel.classfile.ClassParser;
import org.apache.bcel.classfile.Code;
import org.apache.bcel.classfile.JavaClass;
import org.apache.bcel.classfile.Method;


/**
 * @author pugh
 */
public class PrintClass {

	/**
	 * @author pugh
	 */
	static final class ZipEntryComparator implements Comparator<ZipEntry>, Serializable {
		private static final long serialVersionUID = 1L;
		public int compare(ZipEntry o1, ZipEntry o2) {
			ZipEntry e1 = (ZipEntry) o1;
			String s1 = e1.getName();
			int pos1 = s1.lastIndexOf('/');
			String p1 = "-";
			if (pos1 >= 0)
				p1 = s1.substring(0, pos1);

			ZipEntry e2 = (ZipEntry) o2;
			String s2 = e2.getName();
			int pos2 = s2.lastIndexOf('/');
			String p2 = "-";
			if (pos2 >= 0)
				p2 = s2.substring(0, pos2);
			int r = p1.compareTo(p2);
			if (r != 0)
				return r;
			return s1.compareTo(s2);
		}
	}

	static boolean code = false, constants = false;

	public static void main(String argv[]) throws IOException {
		String[] file_name = new String[argv.length];
		int files = 0;
		ClassParser parser = null;
		String zip_file = null;

		/*
		 * Parse command line arguments.
		 */
		for (int i = 0; i < argv.length; i++) {
			if (argv[i].charAt(0) == '-') { // command line switch
				if (argv[i].equals("-constants"))
					constants = true;
				else if (argv[i].equals("-code"))
					code = true;
				else if (argv[i].equals("-zip"))
					zip_file = argv[++i];
			} else if (argv[i].endsWith(".zip") || argv[i].endsWith(".jar"))
				zip_file = argv[i];
			else { // add file name to list
				file_name[files++] = argv[i];
			}
		}

		if (!constants) code = true;
		if (files == 0 && zip_file == null) {
			System.err.println("list: No input files specified");
		} else {

			if (files == 0 && zip_file != null) {
				ZipFile z = new ZipFile(zip_file);
				TreeSet<ZipEntry> zipEntries = new TreeSet<ZipEntry>(
						new ZipEntryComparator());
				for (Enumeration<? extends ZipEntry> e =  z
						.entries(); e.hasMoreElements();)
					zipEntries.add(e.nextElement());

				for (ZipEntry ze : zipEntries) {
					String name = ze.getName();
					if (name.endsWith(".class")) 
						printClass(new ClassParser(z.getInputStream(ze), name));



				}
			} else
				for (int i = 0; i < files; i++)
					if (file_name[i].endsWith(".class")) {
						if (zip_file == null)
							printClass(new ClassParser(file_name[i]));
						else
							printClass(new ClassParser(zip_file, file_name[i]));

					}
		}

	}

	private static void printClass(ClassParser parser) throws IOException {
		JavaClass java_class;
		java_class = parser.parse();

		if (constants || code)
			System.out.println(java_class); // Dump the contents
		if (constants) // Dump the constant pool ?
			System.out.println(java_class.getConstantPool());

		if (code) // Dump the method code ?
			printCode(java_class.getMethods());
	}

	/**
	 * Dump the disassembled code of all methods in the class.
	 */
	public static void printCode(Method[] methods) {
		for (Method m : methods) {
			System.out.println(m);
			Code code = m.getCode();
			if (code != null)
				System.out.println(code);

		}
	}
}