javap(1)javap(1)NAMEjavap - Java class file disassembler
SYNOPSISjavap [ options ] class ...
DESCRIPTION
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() {
resize(500,100);
date = getParameter("LAST_UPDATED");
email = getParameter("EMAIL");
}
public void paint(Graphics g) {
g.drawString(date + " by ",100, 15);
g.drawString(email,290,15);
}
}
The output from javap DocFooter yields:
Compiled from DocFooter.java
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();
}
OPTIONS
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:
.:<your_path>
For example:
.:/home/avh/classes:/usr/local/java/classes
-extdirs dirs Overrides location at which installed extensions are
searched. The default location for extensions is
jre/lib/ext.
-help Prints out help message for javap.
-Jflag Passes flag directly to runtime system.
javap-J-version
javap-JJ-Djava.security.manager
-Djava.security.policy=MyPolicy MyClassName
-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‐
ods.
ENVIRONMENT VARIABLES
CLASSPATH Used to provide the system with a path to user-defined
classes. Directories are separated by colons. For exam‐
ple:
.:/home/avh/classes:/usr/local/java/classes
SEE ALSOjava(1), javac(1), javadoc(1), javah(1), jdb(1)
13 June 2000 javap(1)
