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javap(1)                                                              javap(1)


       javap - Java class file disassembler


       javap [ options ] class ...


       The  javap  command disassembles a Java class file.  The options deter-
       mine the output.  If no options are used, javap prints out the package,
       protected,  and  public fields and methods of the classes passed to it.
       The javap command displays its output to stdout.  For example,  compile
       the following class declaration:
              import java.awt.*;
              import java.applet.*;

              public class DocFooter extends Applet {
                        String date;
                        String email;

                        public void init() {

                             date = getParameter("LAST_UPDATED");
                             email = getParameter("EMAIL");

                        public void paint(Graphics g) {
                             g.drawString(date + " by ",100, 15);

       The output from javap DocFooter yields:

              Compiled from
              public class DocFooter extends java.applet.Applet {
                   java.lang.String date;
                   java.lang.String email;
                   public void init();
                   public void paint(java.awt.Graphics);
                   public DocFooter();


       The following options are supported:

       -b             Ensures backward compatibility with javap in JDK 1.1.

       -bootclasspath path
                      Specifies path from which to load bootstrap classes.  By
                      default, the bootstrap classes are  the  classes  imple-
                      menting the core Java platform located in jre/lib/rt.jar
                      and jre/lib/charsets.jar.

       -c             Prints out disassembled code, that is, the  instructions
                      that  comprise the Java bytecodes, for each of the meth-
                      ods in the class.  These are documented in the Java Vir-
                      tual Machine Specification.

       -classpath path
                      Specifies the path javap uses to look up classes.  Over-
                      rides the default or the CLASSPATH environment  variable
                      if  it is set.  Directories are separated by colons (:).
                      Thus the general format for path is:


                      For example:


       -extdirs dirs  Overrides location at  which  installed  extensions  are
                      searched.    The  default  location  for  extensions  is

       -help          Prints out help message for javap.

       -Jflag         Passes flag directly to runtime system.

                      javap -J-version


       -l             Displays line and local variable tables.

       -package       Shows only package, protected, and  public  classes  and
                      members. This is the default.

       -private       Shows all classes and members.

       -protected     Shows only protected and public classes and members.

       -public        Shows only public classes and members.

       -s             Displays internal type signatures.

       -verbose       Prints  stack size, number of locals, and args for meth-


       CLASSPATH      Used to provide the system with a path  to  user-defined
                      classes. Directories are separated by colons.  For exam-



       java(1), javac(1), javadoc(1), javah(1), jdb(1)

                                 13 June 2000                         javap(1)

Mac OS X 10.7.4 - Generated Thu May 10 07:49:43 CDT 2012
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