ExceptionBuddy

ExceptionBuddy is a Java agent for comprehensive exception monitoring and logging through runtime instrumentation. It captures exceptions across the JVM, including caught exceptions, to improve debugging and production diagnostics.

Features

• Complete exception capture across the JVM
• Non-invasive instrumentation (no application code changes)
• Configurable stack-trace filtering
• Optional class-loader tracing
• Runtime exception statistics monitoring
• Runtime attach support via Attach API
• Optional JVM system property dump
• Optional environment variable dump

How It Works

ExceptionBuddy instruments java.lang.Throwable using the Java Instrumentation API. By instrumenting the base exception type, it captures exception creation events regardless of where they are later handled.

Getting Started

Prerequisites

• Java 8 or higher
• A target JVM application

Launch-Time Agent

java -javaagent:C:\tools\ExceptionBuddy-1.0-SNAPSHOT.jar=configurationFile=C:\tools\ebConfig.json -jar your-application.jar

Runtime Attach

java -cp ExceptionBuddy-1.0-SNAPSHOT.jar com.asm.eb.attach.AgentAttachCLI --agentJar C:\tools\ExceptionBuddy-1.0-SNAPSHOT.jar --configurationFile C:\tools\ebConfig.json --pid <target-jvm-pid>

Configuration

Create ebConfig.json:

{
  "useFilters": true,
  "filters": ["org.apache.logging.log4j"],
  "logFilePath": "C:\\tools\\eb.log",
  "classLoaderTracing": false,
  "exceptionMonitoring": false,
  "cnfSkipString": "java.lang.ClassLoader.loadClass(ClassLoader.java:406)",
  "printJVMSysProps": false,
  "printEnvironmentVariables": false
}

Notes:

• classLoaderTracing can produce high log volume and should be enabled only for focused diagnostics.
• printJVMSysProps and printEnvironmentVariables can expose secrets; keep them disabled by default in production.
• If useFilters is true, filters must contain at least one non-empty entry.
• Runtime config reload is not supported yet; config is read once at startup attach or runtime attach.

Building from Source

git clone https://github.com/AshutoshIWNL/ExceptionBuddy.git
cd ExceptionBuddy
mvn clean test package

Contributing

Contributions are welcome through issues and pull requests.