A simple CLI wrapper around ObjectWeb's Asmifier.
Pass a java .class file path to generate the ASM code necessary to generate the .class file.
Releases are available here
git clone git@github.com:jackhenry/asmifier-cli.git
cd asmifier-cli
./gradlew build
A distribution zip and tar will be generated in ./app/build/distributions
Additionally, a jar file with be generated in ./app/build/libs
Usage: asmifier cli [-o[=<outputFilePath>]] [-p[=<parseOption>]] <classFilePath>
Simple CLI wrapper around asmifier. Convert a class file to ASM code that
generates the class file.
<classFilePath> File path to the class file which will be asmified
-o, --output[=<outputFilePath>]
Optional file path to write asmifier output into
-p, --parseoption[=<parseOption>]
Parse Options: SKIP_CODE, SKIP_DEBUG, SKIP_FRAMES,
EXPAND_FRAMES
Default: EXPAND_FRAMES
./asmifier-cli path/to/HelloWorld.class
HelloWorld.class
Classfile HelloWorld.class
Last modified Mar 7, 2021; size 485 bytes
SHA-256 checksum f748d932217a27d1ae2dee9af8918294849511b5521002f76bf931512b8c0cc7
Compiled from "HelloWorld.java"
public class HelloWorld
minor version: 65535
major version: 55
flags: (0x0021) ACC_PUBLIC, ACC_SUPER
this_class: #5 // HelloWorld
super_class: #6 // java/lang/Object
interfaces: 0, fields: 0, methods: 2, attributes: 1
Constant pool:
#1 = Methodref #6.#17 // java/lang/Object."<init>":()V
#2 = Fieldref #18.#19 // java/lang/System.out:Ljava/io/PrintStream;
#3 = String #20 // Hello, World!
#4 = Methodref #21.#22 // java/io/PrintStream.println:(Ljava/lang/String;)V
#5 = Class #23 // HelloWorld
#6 = Class #24 // java/lang/Object
#7 = Utf8 <init>
#8 = Utf8 ()V
#9 = Utf8 Code
#10 = Utf8 LineNumberTable
#11 = Utf8 LocalVariableTable
#12 = Utf8 this
#13 = Utf8 LHelloWorld;
#14 = Utf8 greeting
#15 = Utf8 SourceFile
#16 = Utf8 HelloWorld.java
#17 = NameAndType #7:#8 // "<init>":()V
#18 = Class #25 // java/lang/System
#19 = NameAndType #26:#27 // out:Ljava/io/PrintStream;
#20 = Utf8 Hello, World!
#21 = Class #28 // java/io/PrintStream
#22 = NameAndType #29:#30 // println:(Ljava/lang/String;)V
#23 = Utf8 HelloWorld
#24 = Utf8 java/lang/Object
#25 = Utf8 java/lang/System
#26 = Utf8 out
#27 = Utf8 Ljava/io/PrintStream;
#28 = Utf8 java/io/PrintStream
#29 = Utf8 println
#30 = Utf8 (Ljava/lang/String;)V
{
public HelloWorld();
descriptor: ()V
flags: (0x0001) ACC_PUBLIC
Code:
stack=1, locals=1, args_size=1
0: aload_0
1: invokespecial #1 // Method java/lang/Object."<init>":()V
4: return
LineNumberTable:
line 1: 0
LocalVariableTable:
Start Length Slot Name Signature
0 5 0 this LHelloWorld;
public void greeting();
descriptor: ()V
flags: (0x0001) ACC_PUBLIC
Code:
stack=2, locals=1, args_size=1
0: getstatic #2 // Field java/lang/System.out:Ljava/io/PrintStream;
3: ldc #3 // String Hello, World!
5: invokevirtual #4 // Method java/io/PrintStream.println:(Ljava/lang/String;)V
8: return
LineNumberTable:
line 3: 0
line 4: 8
LocalVariableTable:
Start Length Slot Name Signature
0 9 0 this LHelloWorld;
}
SourceFile: "HelloWorld.java"output
import org.objectweb.asm.AnnotationVisitor;
import org.objectweb.asm.Attribute;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.ConstantDynamic;
import org.objectweb.asm.FieldVisitor;
import org.objectweb.asm.Handle;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.RecordComponentVisitor;
import org.objectweb.asm.Type;
import org.objectweb.asm.TypePath;
public class HelloWorldDump implements Opcodes {
public static byte[] dump() throws Exception {
ClassWriter classWriter = new ClassWriter(0);
FieldVisitor fieldVisitor;
RecordComponentVisitor recordComponentVisitor;
MethodVisitor methodVisitor;
AnnotationVisitor annotationVisitor0;
classWriter.visit(-65481, ACC_PUBLIC | ACC_SUPER, "HelloWorld", null, "java/lang/Object", null);
classWriter.visitSource("HelloWorld.java", null);
{
methodVisitor = classWriter.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
methodVisitor.visitCode();
Label label0 = new Label();
methodVisitor.visitLabel(label0);
methodVisitor.visitLineNumber(1, label0);
methodVisitor.visitVarInsn(ALOAD, 0);
methodVisitor.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V", false);
methodVisitor.visitInsn(RETURN);
Label label1 = new Label();
methodVisitor.visitLabel(label1);
methodVisitor.visitLocalVariable("this", "LHelloWorld;", null, label0, label1, 0);
methodVisitor.visitMaxs(1, 1);
methodVisitor.visitEnd();
}
{
methodVisitor = classWriter.visitMethod(ACC_PUBLIC, "greeting", "()V", null, null);
methodVisitor.visitCode();
Label label0 = new Label();
methodVisitor.visitLabel(label0);
methodVisitor.visitLineNumber(3, label0);
methodVisitor.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
methodVisitor.visitLdcInsn("Hello, World!");
methodVisitor.visitMethodInsn(INVOKEVIRTUAL, "java/io/PrintStream", "println", "(Ljava/lang/String;)V", false);
Label label1 = new Label();
methodVisitor.visitLabel(label1);
methodVisitor.visitLineNumber(4, label1);
methodVisitor.visitInsn(RETURN);
Label label2 = new Label();
methodVisitor.visitLabel(label2);
methodVisitor.visitLocalVariable("this", "LHelloWorld;", null, label0, label2, 0);
methodVisitor.visitMaxs(2, 1);
methodVisitor.visitEnd();
}
classWriter.visitEnd();
return classWriter.toByteArray();
}
}