**Have you ever** _System-d dot out_ an Object and got its class name @ its hexadecimal hashcode?

Chances are: it wasn’t what you were hoping for and it didn’t you help much.

The problem is that, in Java, we lack a function which generates a good and consistent textual representation for any Java object.

If we had it, we would write:

System.out.println( **toString**.apply(myObject) ); 

instead of

System.out.println( myObject**.toString()** ); _// finger crossed, we   
                                           // have a good toString._

We would then stop cursing at developers for not implementing a damn good _toString_.

**Hacking a universal _toString_** is easy, if you decide to ignore a few edge cases.

It just requires you to use the reflection API to iterate over all the object’s fields to print them.

[I wrote one](https://gist.github.com/lorenzoongithub/d1a7e047b29aef79d363b3b56c2e666a) that you can use with [Nashorn jjs](https://docs.oracle.com/javase/8/docs/technotes/guides/scripting/nashorn/shell.html), with [nudge4j](https://lorenzoongithub.github.io/nudge4j/) and in any Java 8 program.

It’s written as a Nashorn JavaScript function. The function pretty much delegates all of the work to the poorly named _ReflectionToStringBuilder_ (part of [Apache Commons Lang](https://commons.apache.org/proper/commons-lang/)).

You don’t need Apache Commons Lang in your classpath (I don’t have it either). I hate dependencies and I am not going to ask you to add it just for this. The code comes with [a good trick](http://stackoverflow.com/questions/60764/how-should-i-load-jars-dynamically-at-runtime) to load it on demand from the maven repo.

**How do we use the toString function ?**

In Nashorn jjs and nudge4j you load it and you are ready to go:

load("[https://gist.githubusercontent.com/lorenzoongithub/d1a7e047b29aef79d363b3b56c2e666a/raw/c486452e25d0f419101ae7bddd259240b17f1762/toString.js](https://gist.githubusercontent.com/lorenzoongithub/d1a7e047b29aef79d363b3b56c2e666a/raw/c486452e25d0f419101ae7bddd259240b17f1762/toString.js)")  
toString(java.lang.Thread.currentThread());

In Java you need to write a bit of boiler plate to wrap it up as a Java Function:

Function<Object, String> toString = new Function<Object,String>() {  
  private ScriptEngine engine;  
     
  {  
    try {  
      engine = new ScriptEngineManager().  
                      getEngineByName("JavaScript");  
      try (InputStream is = new URL("[https://gist.githubusercontent.com/lorenzoongithub/d1a7e047b29aef79d363b3b56c2e666a/raw/c486452e25d0f419101ae7bddd259240b17f1762/toString.js](https://gist.githubusercontent.com/lorenzoongithub/d1a7e047b29aef79d363b3b56c2e666a/raw/c486452e25d0f419101ae7bddd259240b17f1762/toString.js)").openStream()) {

        engine.eval(new InputStreamReader(  
          is, StandardCharsets.UTF\_8));  
      }  
    } catch (ScriptException | IOException e) {  
      throw new RuntimeException(e);  
    }  
  }

  public String apply(Object oj) {  
    try {  
      return ""+  
        ((Invocable)engine).invokeFunction("toString", oj);  
    } catch (NoSuchMethodException | ScriptException e) {  
      throw new RuntimeException(e);  
    }  
  }  
};

System.out.println(toString.apply(Thread.currentThread()));

**And that’s it**: a universal function to stringify any Java Object.

It won’t have an impact on your day to day work but it might turn handy on one of those _debugging_ days.

Debug less.

![](https://hackernoon.com/hn-images/1*TGPia95dg7f3F3gwRjTdgA.png)

loading toString.js in [nudge4j](https://lorenzoongithub.github.io/nudge4j/)

A blooming good Java toString for the rest of us

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