CrossRef.java Source code

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Here is the source code for CrossRef.java

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/*
 * Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
 * All rights reserved. Software written by Ian F. Darwin and others.
 * $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Java, the Duke mascot, and all variants of Sun's Java "steaming coffee
 * cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's,
 * pioneering role in inventing and promulgating (and standardizing) the Java 
 * language and environment is gratefully acknowledged.
 * 
 * The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
 * inventing predecessor languages C and C++ is also gratefully acknowledged.
 */

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import java.util.StringTokenizer;
import java.util.zip.ZipEntry;
import java.util.zip.ZipException;
import java.util.zip.ZipFile;

/**
 * CrossRef prints a cross-reference about all classes named in argv.
 * For each class, all public fields and methods are listed.
 * "Reflectance" is used to look up the information.
 *
 * It is expected that the output will be post-processed e.g.,
 * with sort and awk/perl. Try: 
   java CrossRef | 
  uniq | # squeeze out polymorphic forms early
  sort | awk '$2=="method" { ... }' > crossref-methods.txt
 * The part in "{ ... }" is left as an exercise for the reader. :-(
 *
 * @author   Ian Darwin, Ian@DarwinSys.com
 * @version   $Id: CrossRef.java,v 1.16 2003/04/08 20:01:44 ian Exp $
 */
public class CrossRef extends APIFormatter {

    /** Simple main program, construct self, process each .ZIP file
     * found in CLASSPATH or in argv.
     */
    public static void main(String[] argv) throws IOException {
        CrossRef xref = new CrossRef();
        xref.doArgs(argv);
    }

    /**
     * Print the fields and methods of one class.
     */
    protected void doClass(Class c) {
        int i, mods;
        startClass(c);
        try {
            Field[] fields = c.getDeclaredFields();
            Arrays.sort(fields, new Comparator() {
                public int compare(Object o1, Object o2) {
                    return ((Field) o1).getName().compareTo(((Field) o2).getName());
                }
            });
            for (i = 0; i < fields.length; i++) {
                Field field = (Field) fields[i];
                if (!Modifier.isPrivate(field.getModifiers()))
                    putField(field, c);
                // else System.err.println("private field ignored: " + field);
            }

            Method methods[] = c.getDeclaredMethods();
            // Arrays.sort(methods);
            for (i = 0; i < methods.length; i++) {
                if (!Modifier.isPrivate(methods[i].getModifiers()))
                    putMethod(methods[i], c);
                // else System.err.println("pvt: " + methods[i]);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        endClass();
    }

    /** put a Field's information to the standard output.  */
    protected void putField(Field fld, Class c) {
        println(fld.getName() + " field " + c.getName() + " ");
    }

    /** put a Method's information to the standard output.  */
    protected void putMethod(Method method, Class c) {
        String methName = method.getName();
        println(methName + " method " + c.getName() + " ");
    }

    /** Print the start of a class. Unused in this version,
     * designed to be overridden */
    protected void startClass(Class c) {
    }

    /** Print the end of a class. Unused in this version,
     * designed to be overridden */
    protected void endClass() {
    }

    /** Convenience routine, short for System.out.println */
    protected final void println(String s) {
        System.out.println(s);
    }
}

/**
 * <p>
 * APIFormatter reads one or more Zip files, gets all entries from each
 * and, for each entry that ends in ".class", loads it with Class.forName()
 * and hands it off to a doClass(Class c) method declared in a subclass.
 * <br/>TODO<br/>
 * Use GETOPT to control doingStandardClasses, verbosity level, etc.
 * @author   Ian Darwin, Ian@DarwinSys.com
 * @version   $Id: APIFormatter.java,v 1.6 2004/03/14 14:00:34 ian Exp $
 */
abstract class APIFormatter {

    /** True if we are doing classpath, so only do java. and javax. */
    protected static boolean doingStandardClasses = true;

    protected int doArgs(String[] argv) throws IOException {
        /** Counter of fields/methods printed. */
        int n = 0;

        // TODO: options
        // -b - process bootclasspath
        // -c - process classpath (default)
        // -s - only process "java." and "javax."

        if (argv.length == 0) {
            // No arguments, look in CLASSPATH
            String s = System.getProperty("java.class.path");
            //  break apart with path sep.
            String pathSep = System.getProperty("path.separator");
            StringTokenizer st = new StringTokenizer(s, pathSep);
            // Process each zip in classpath
            while (st.hasMoreTokens()) {
                String thisFile = st.nextToken();
                System.err.println("Trying path " + thisFile);
                if (thisFile.endsWith(".zip") || thisFile.endsWith(".jar"))
                    processOneZip(thisFile);
            }
        } else {
            // We have arguments, process them as zip/jar files
            // doingStandardClasses = false;
            for (int i = 0; i < argv.length; i++)
                processOneZip(argv[i]);
        }

        return n;
    }

    /** For each Zip file, for each entry, xref it */
    public void processOneZip(String fileName) throws IOException {
        List entries = new ArrayList();
        ZipFile zipFile = null;

        try {
            zipFile = new ZipFile(new File(fileName));
        } catch (ZipException zz) {
            throw new FileNotFoundException(zz.toString() + fileName);
        }
        Enumeration all = zipFile.entries();

        // Put the entries into the List for sorting...
        while (all.hasMoreElements()) {
            ZipEntry zipEntry = (ZipEntry) all.nextElement();
            entries.add(zipEntry);
        }

        // Sort the entries (by class name)
        // Collections.sort(entries);

        // Process all the entries in this zip.
        Iterator it = entries.iterator();
        while (it.hasNext()) {
            ZipEntry zipEntry = (ZipEntry) it.next();
            String zipName = zipEntry.getName();

            // Ignore package/directory, other odd-ball stuff.
            if (zipEntry.isDirectory()) {
                continue;
            }

            // Ignore META-INF stuff
            if (zipName.startsWith("META-INF/")) {
                continue;
            }

            // Ignore images, HTML, whatever else we find.
            if (!zipName.endsWith(".class")) {
                continue;
            }

            // If doing CLASSPATH, Ignore com.* which are "internal API".
            //    if (doingStandardClasses && !zipName.startsWith("java")){
            //       continue;
            //    }

            // Convert the zip file entry name, like
            //   java/lang/Math.class
            // to a class name like
            //   java.lang.Math
            String className = zipName.replace('/', '.').substring(0, zipName.length() - 6); // 6 for ".class"

            // Now get the Class object for it.
            Class c = null;
            try {
                c = Class.forName(className);
            } catch (ClassNotFoundException ex) {
                System.err.println("Error: " + ex);
            }

            // Hand it off to the subclass...
            doClass(c);
        }
    }

    /** Format the fields and methods of one class, given its name.
     */
    protected abstract void doClass(Class c) throws IOException;
}