Questions tagged [byte-buddy]

Byte Buddy is a code generation and manipulation library for creating and modifying Java classes during the runtime of a Java application and without the help of a compiler. Byte Buddy allows the creation of arbitrary classes and is not limited to implementing interfaces for the creation of runtime proxies. Furthermore, Byte Buddy offers a convenient API for changing classes either manually, using a Java agent or during a build.

Byte Buddy is a code generation and manipulation library for creating and modifiying Java classes during the runtime of a Java application and without the help of a compiler. Other than the code generation utilities that ship with the Java Class Library, Byte Buddy allows the creation of arbitrary classes and is not limited to implementing interfaces for the creation of runtime proxies. Furthermore, Byte Buddy offers a convenient API for changing classes either manually, using a Java agent or during a build.

In order to use Byte Buddy, one does not require an understanding of Java byte code or the class file format. In contrast, Byte Buddy's API aims for code that is concise and easy to understand for everybody. Nevertheless, Byte Buddy remains fully customizable down to the possibility of defining custom byte code. Furthermore, the API was designed to be as non-intrusive as possible and as a result, Byte Buddy does not leave any trace in the classes that were created by it. For this reason, the generated classes can exist without requiring Byte Buddy on the class path. Because of this feature, Byte Buddy's mascot was chosen to be a ghost.

Byte Buddy is written in Java 6 but supports the generation of classes for any Java version. Byte Buddy is a light-weight library and only depends on the visitor API of the Java byte code parser library ASM which does itself not require any further dependencies.

749 questions
0
votes
1 answer

Can I instrument outgoing method/constructor calls with ByteBuddy?

I have a project where I was using Javassist to log outgoing method/constructor calls with code like this: CtMethod cm = ... ; cm.instrument( new ExprEditor() { public void edit(MethodCall m) throws CannotCompileException …
0
votes
1 answer

can byte buddy be used as debugger

Is it possible to use byte-buddy in order to record all method calls, variables at some points in time, exceptions that happened and line numbers? I wanted to record all this data in java app.
Marko Kraljevic
  • 401
  • 4
  • 19
0
votes
1 answer

Byte Buddy Nested Annotations

I would like to use Byte-Buddy to generate annotations and I am able to accomplish this for simple annotations. What is the correct Byte-Buddy syntax to generate nested annotations? For example I would like to generate the following annotation…
ckeenan
  • 21
  • 2
0
votes
1 answer

bytecode tools: add method interceptor to classes (not proxy)

Javassist proxyFactory can create proxy at runtime with method interceptor. But how to add method interceptor to a class statically by modifying the class file? For example, class Foo has 100 methods, before calling any method on an instance of Foo,…
eastwater
  • 4,624
  • 9
  • 49
  • 118
0
votes
1 answer

what is the alternative for dynamic class loading in java?

I'm using reflection to load the class at run-time but sonar rules are pointing it as vulnerability attack i'm thinking to use ByteBuddy,can bytebuddy library help me on this? ClassLoader classLoader = MyClass.class.getClassLoader(); Class
Tirumalesh
  • 95
  • 1
  • 17
0
votes
1 answer

how to find all methods called in a methods including Lamda?

I would like to list all methods called by a method. void create() throws MyException { System.out.println("TEST"); of("String").map(String::valueOf).get(); } In this method i would like to list…
Trind
  • 1,583
  • 4
  • 18
  • 38
0
votes
1 answer

Can's defined new field to loading class

I use bytebuddy-agent to add a dynamic field for Jedis class, and in JedisCluster constructor, there will be three Jedis instance created which will cause JVM loading Jedis class. What make me confused is that when I put code Jedis jedis = new…
MengZhi
  • 51
  • 5
0
votes
0 answers

ByteBuddy Agent: If intercepting methods, the JUnit test fail

I am trying to analyse JUnit tests with ByteBuddy (1.7.5) dynamically, so I don't know them in advance. I am loading them through the run() method below, and intercepting with the Agent built with the Agent() method below. The unit tests work as…
Jacktraror
  • 90
  • 8
0
votes
2 answers

How to access runtime information in @Advice.OnMethodEnter/Exit ?

I am using Bytebuddy to instrument methods. Is there any way of getting hold of runtime information as e.g. the thread id of the instrumented method/constructor ? I couldn't find a way to gain access to this information using @Advice.*
Ben
  • 191
  • 3
  • 13
0
votes
1 answer

Create a proxy object using byte buddy

I am trying to create proxy object using Byte Buddy. I actually want to mock any dependencies in any class and if any method is called on that depended object it will return a per-determined value to the caller. public class Person{ private String…
Andy
  • 1
  • 3
0
votes
2 answers

how to intercept a method with specific parameters with bytebuddy

I want to intercept method named methodA with one arg which's type is String as blow, what should i do. How to use hasParameters() api? public class Demo { public static void main(String[] args) { new ByteBuddy() …
MengZhi
  • 51
  • 5
0
votes
1 answer

Java - Create anonymous Exception subclass with a certain name

We're using Fabric / Crashlytics for sending non-crash issues to their servers and later checking out the logs and stacktraces. Unfortunately, the Crashlytics API requires to use a different Exception subclass instance for different issue types. (In…
keyboard
  • 2,137
  • 1
  • 20
  • 32
0
votes
1 answer

Get execution path with ByteBuddy

Im trying to get the execution path of an application. To get in touch with ByteBuddy i implemented an agent using the code below but it doesn´t print out anything. Can anyone help me? public static void premain(String arg, Instrumentation inst)…
Hector Lorenzo
  • 141
  • 3
  • 11
0
votes
1 answer

How to use ByteBuddy in a java project

I made a simple project of java to test ByteBuddy . I typed exactly the same code in a tutorial made by Rafael Winterhalter but it showing some errors 1) ByteBuddyAgent cannot be resolved. 2) type cannot be resolved to a variable. 3)…
Md. Shohag Mia
  • 322
  • 3
  • 13
0
votes
1 answer

Intercept Error constructor with bytebuddy

For some reason I can't work out yet, my agent doesn't intercept java LinkageError instances. Agent code: import net.bytebuddy.agent.builder.AgentBuilder; import net.bytebuddy.implementation.MethodDelegation; import…
dgt
  • 1,002
  • 8
  • 10