//
//
//  Classpath - List all classes in Java Classpath
//
//  Usage: java Classpath [classpath]
//
//  This program will search recursively through the environment variable
//   CLASSPATH or a classpath entered on the command line.
//
//

import java.io.*;
import java.util.*;
import java.util.jar.*;

public class Classpath {
    static int depth;

    static String stringSet(String str, int n) throws IllegalArgumentException {
        if (n < 0)
            throw new IllegalArgumentException("n < 0");

        String result = "";
        for (int i=0; i<n; i++)
            result = result.concat(str);

        return result;
    }

    static void searchJarFile(JarFile jarFile) throws IOException {
        ++depth;
        // list all .class files in this jar
        for (Enumeration<JarEntry> entries = jarFile.entries();
         entries.hasMoreElements();) {
            JarEntry entry = entries.nextElement();
            String name = entry.getName();
            if (name.endsWith(".class"))
                System.out.println(stringSet("    ",depth) + name);
        }
        // check jar files for a manifest classpath
        Manifest manifest = jarFile.getManifest();
        if (manifest != null) {
            Attributes atts = manifest.getMainAttributes();
            String jarClassPath = atts.getValue("Class-Path");
            // if it has a classpath
            if (jarClassPath != null) {
                String[] jarPaths = jarClassPath.split(File.pathSeparator);
                for (int j=0; j<jarPaths.length; j++) {
                    System.out.println(stringSet("    ",depth) + jarPaths[j]);
                    jarFile = new JarFile(jarPaths[j]);
                    searchJarFile(jarFile);  // recursive call
                }
            }
        }
        --depth;
    }

    static class ClassFilter implements FileFilter {
        final String endsWith;

        public ClassFilter(String endsWith) {
            this.endsWith = endsWith;
        }

        public boolean accept(File pathname) {
            return pathname.getName().endsWith(endsWith);
        }
    }

    public static void main(String[] args) {
        String classpath = System.getenv("CLASSPATH");
        if (classpath == null) {
            System.out.println("No Java Classpath environment variable set");
            return;
        }
        String[] paths;
        if (args.length == 0)
            paths = classpath.split(File.pathSeparator);
        else
            paths = args[0].split(File.pathSeparator);

        for (int i=0; i<paths.length; i++) {
            File file = new File(paths[i]);
            // classpath ends with an * - all .jar files in directory
            if (paths[i].endsWith("*")) {
                System.out.println(paths[i]);
                paths[i] = paths[i].replaceAll("\\*","");
                file = new File(paths[i]);
                File[] jarFiles = file.listFiles(new ClassFilter(".jar"));
                for (int j=0; j<jarFiles.length; j++) {
                    System.out.println(jarFiles[j].getName());
                    try {
                        searchJarFile(new JarFile(jarFiles[j]));
                    } catch (IOException ioe) {
                        System.out.println(ioe);
                    }
                }
            // classpath is a directory - all .class files in directory
            } else if (file.isDirectory()) {
                System.out.println(paths[i]);
                File[] classFiles = file.listFiles(new ClassFilter(".class"));
                for (int j=0; j<classFiles.length; j++)
                    System.out.println(classFiles[j].getName());
            // classpath is a .jar or .zip file - all .class files in archive
            } else if (paths[i].endsWith(".jar")||paths[i].endsWith(".zip")) {
                System.out.println(paths[i]);
                try {
                    JarFile jarFile = new JarFile(file);
                    searchJarFile(jarFile);
                } catch (IOException ioe) {
                    System.out.println(ioe);
                }
            } else
                System.out.println("Bad path: " + paths[i]);
        }
    }
}