Can I use ArrayList in Data?

Hello, I want to show each data in ArrayList with foreach loop with using json file. This is my json file

```
{
"id": "test-workflow",
"version": 1,
"dataType": "io.blt.MyData",
"steps": [
{
"id": "step1",
"stepType": "io.steps.Hello",
"nextStepId": "step2"
},
{
"id": "step2",
"stepType": "net.jworkflow.primitives.Foreach",
"nextStepId": "step3",
"inputs": {
"collection": "data.values.toArray(new Object[0])"
},
"thenDo": [
[
{
"id": "step2.1",
"stepType": "io.steps.PrintMessage",
"inputs": {
"message": "'doing 2.1' + data.values.toArray(new Object[0])[step.index]"
}
}
]
]
},
{
"id": "step3",
"stepType": "io.steps.Goodbye"
}
]
}

```

MyData class is

```
public class MyData {
public int value1;
public int value2;
public int value3;
public List values = new ArrayList<>();
public Object[] collection1;
}

```

and PrintMessage class is

```

public class PrintMessage implements StepBody {

public String message;
public int index;

@Override
public ExecutionResult run(StepExecutionContext context) {
System.out.println(message);
index++;
return ExecutionResult.next();
}
}

```

Error:
```
java.lang.RuntimeException: javax.script.ScriptException: TypeError: Object[0] is not a function in at line number 1

```

when I use primitive array instade of ArrayList then It works. But I want to use ArrayList. Can I use?
One more thing, Can I get each value of the array without declare extra index in PrintMessage class.