classfile command

use it for

The report includes classes, methods, fields, descriptors, and archive metadata. It does not recover a buildable source tree.

Run glaurung classfile --help on your installed version before putting the command in a script. Glaurung is still pre-1.0.

input: A Java .class file, JAR, or ZIP archive.
output: Classfile version, class hierarchy, access flags, fields, methods, descriptors, and archive counts.
mode: read only. The examples leave the input unchanged.

command shape

syntax

short form

$ glaurung classfile PATH [--json]

The installed parser is authoritative: glaurung classfile --help

run it

examples

Inventory a JAR without a model

classfile is the cheap first pass before Java agent or recovery workflows.

run

from the engine checkout

$ glaurung classfile samples/binaries/platforms/windows/amd64/export/java/jdk17/HelloWorld.jar

output

captured result captured tutorial fixture, shortened

# HelloWorld.jar: 1 class file(s)

class HelloWorld  (Java 17 (classfile 61.0))
  extends java/lang/Object
  access: public
  fields: 3
    private static final GLOBAL_COUNTER: I
    private              message: Ljava/lang/String;
  methods: 6
    public <init>(Ljava/lang/String;)V
    public printMessage()V
    public static main([Ljava/lang/String;)V

captured tutorial fixture, shortened.

Read the result: Descriptors preserve JVM types exactly. This is metadata inspection, not recovered Java source.

Filter the method list

Plain output composes with ordinary shell tools when you need a quick inventory.

run

from the engine checkout

$ glaurung classfile samples/binaries/platforms/windows/amd64/export/java/jdk17/HelloWorld.jar --no-color | rg '^    public'

output

captured result captured from the checked-in JAR, 2026-08-31

public                   <init>(Ljava/lang/String;)V
public                   <init>()V
public                   printMessage()V
public                   getCounter()I
public static            printGlobalInfo()V
public static            main([Ljava/lang/String;)V

captured from the checked-in JAR, 2026-08-31.

Read the result: This filter shows public methods only. It drops the class header and private members, so keep the unfiltered report when completeness matters.

used above

important options

--no-color: Keep plain text when redirecting or filtering.
--quiet: Suppress non-result messages.
--verbose: Print additional parser detail.

These are the flags used by the examples. Run glaurung classfile --help for the complete parser help.

keep working

related commands

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